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APPLICATION NOTE
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
CONTENTS
I. I.1. I.2. I.3. I.4. II. II.1. II.1.1. II.1.2. II.1.3. II.1.4. II.2. II.3. II.3.1. II.3.2. II.3.3. II.3.4. II.3.5. II.4. II.4.1. II.4.2. II.4.3. II.4.4. II.5. II.5.1. II.5.2. II.5.3. II.5.4. II.5.5. II.6. III. III.1. III.2. III.3. III.4. III.5. III.6. III.7. III.8. TEA7092 GENERAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SETTING THE TEA7092 APPLICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PINOUT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . BLOCK DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . INPUT/OUPUT CONFIGURATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SPEECH FEATURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DC CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TEA7092 DC Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Telephone Set DC Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Start Up Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Further Information (VCC/VREF/IREF/VMC/VRMC/VLS/VREFL) . . . . . . . . . . . . . . . . . . . . . . . IMPEDANCE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TRANSMIT CHANNEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . General Information - Maximum Gain Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Softclipping Threshold (Maximum Line Level). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Line Loss Compensation A.G.C. Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A.G.C. Inhibition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Transmit Squelch / Antiacoustic Feedback Stage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SIDETONE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . General Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . One Sidetone Network Principle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Line Tracking Sidetone Network Principle. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sidetone Programming for PABX Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . RECEIVE CHANNEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . General Information - Maximum Gain Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Maximum Output Level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Line Loss Compensation / A.G.C. Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A.G.C. Inhibition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +6dB Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HANDSFREE INTERFACE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CALL PROGRESS MONITOR AND GROUP LISTENING MODES . . . . . . . . . . . . . . . GENERAL INFORMATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . LOUDSPEAKING PART SUPPLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SOFTCLIPPING STAGE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ANTIACOUSTIC FEEDBACK FEATURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MAXIMUM OUTPUT POWER. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . EXTERNAL POWER SUPPLY FACILITY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . RING MELODY CONTROL MODE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . BEEP ERROR GENERATOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Pages
3 3 4 5 6 14 14 14 14 15 17 18 19 19 20 21 21 22 23 23 24 24 25 26 26 27 30 30 30 30 31 31 32 33 33 35 36 37 38
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AN848/1096
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT CONTENTS (continued)
IV. IV.1. IV.2. IV.3. IV.3.1. IV.3.2. IV.3.3. IV.4. IV.5. IV.6. V. V.1. V.2. V.3. VI. VI.1. VI.2. VI.3. VI.4. VI.4.1. VI.4.2. VI.4.3. VI.5. VI.6. VII. MICROCONTROLLER INTERFACE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MICROCONTROLLER POWER SUPPLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . RESET AND PON SIGNALS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SERIAL BUS INTERFACE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Different Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Software Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Serial Bus Codes Actions on Switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . RING INDICATOR / LINE CURRENT VARIATION INDICATOR . . . . . . . . . . . . . . . . . . OSCILLATOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MICROCONTROLLER SIGNAL CONTROL IN THE DIFFERENT MODES. . . . . . . . . . DIALER FEATURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DTMF DIALER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SINE WAVE GENERATOR. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PULSE DIALER INTERFACE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . RINGER FEATURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . RINGER POWER SUPPLY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . START UP THRESHOLD LEVEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . RING FREQUENCY GENERATOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . OUTPUT POWER OPTIMIZATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Switch Mode Power Supply Concept . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Switch Mode Power Supply Losses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Output Power Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MICROCONTROLLER MANAGEMENT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . RING SOFTWARE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . APPLICATION DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Pages
39 39 39 41 41 45 46 47 47 47 48 48 49 49 50 50 50 51 51 51 52 53 54 55 56
2/57
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
I - TEA7092 GENERAL INFORMATION I.1 - Setting the TEA7092 Application TEA7092 is a telephone set integrated circuit designed to meet various country's requirements. TEA7092 is adapted to each country through external component value modifications. TEA7092 performs the following features : - Speech (Line interface & 2 wires / 4 wires) - Call progress monitor (Exchange tone heard in the loudpeaker & On-Hook dialing) - Group listening (Handset & loudspeaker used simultaneously) - Handfree interface - Ring on Loudspeaker - DTMF dialing - DC mask in Pulse dialing mode (Tip & Ring voltage reduced during make period) - Microcontroller interface - Line current variation detector for transfer - Waiting melody generator - Beep error generator All these features can be programmed by the associated microcontroller through the serial bus interface. Make a copy of the last page of this document and keep it as a reference, when you read this application note, if you want to refer to the external component names. When setting the application, it is preferable to respect the following flow chart : Speech Part and DTMF Dialing - Start your application with the default component values given at the last page of this document (typical application). - Adjust the DC and START-UP characteristics. - Adjust the Impedance (return loss). - Adjust the Transmit parameters (softclipping level, gain, frequency response curve). - Adjust the Sidetone network(s)*. - Adjust the Receive parameters (gain, frequency response curve)*. - Adjust the DTMF output level.
* Each of these two adjustments is influenced by the other one, for more information, see Sections II.4 & II.5.
Call Progress Monitor and Group Listening - Adjust the Loudspeaking amplifier (gain, frequency response curve) without handsetconnection in order to avoid influence of the handset microphone. - Adjust the Antiacoustic feedback efficiency. Ringer Part - Choose the Ring frequency melody. - Adjust the Ring start up level. - Optimize the loudspeaker output power. Further Features - Tip & Ring DC value in the make period in pulse dialing mode, - Line current variation detector for transfer, - Waiting melody generator, - Beep error generator, - Microcontroller interface, are essentialy software programming. Note : Throughout the application note, IL is the current which power supplies the complete application (current is equivalent to the one delivered by an exchange to power a telephone set). For the entire application note, unless otherwise specified, the component values are those given at the last page of this document (typical application).
3/57
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
I - TEA7092 GENERAL INFORMATION (continued) I.2 - Pinout
Pin N 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44
* Logic Interface.
Name VLS VMC VL VREFL LSIN LSSOF DTMF1 VRMC OSC RI/VI RESET PON CLK DATA SNSL SNLL ASQ ASC RECIN REOUT GTR HFIN MIC1 MIC2 VREF VCC TSOFT SOFTL IREF VS SLPE AGND ILL ISL EAR+ EARGREC VZP SWP RSU RCO DTMF2 GND LSOUT Loudspeaker Power Supply
Function Unregulated Microcontroller Power Supply Transmit Output Stage Loudspeaker Reference Voltage (VLS/2) Loudspeaker Amplifier Input Loudspeaker Softclipping Time Constant DTMF Filter 1 Stabilized Microcontroller Power Supply Oscillator Input Ring Indicator/Line Current Variation Indicator Output (*) Microcontroller Reset Output (*) Line Current Indicator Output (*) Serial Bus Clock Input (*) Serial Bus Data Input (*) Short Line Sidetone Network Long Line Sidetone Network Anti-Acoustic Feedback and Squelch Time Constant DC Offset Anti-Acoustic Feedback and Squelch Amplifier Suppression Receive Input and Positive Line Voltage Receive Output for Handfree Interface and Loudspeaker Input Transmit Gain Adjustment Handfree Microphone Input Referenced to VREF Microphone Input 1 Referenced to VREF Microphone Input 2 Referenced to VREF Speech Reference Voltage (VCC/2) Speech Power Supply Transmit Softclipping Time Constant Transmit Softclipping Level Adjustment Resistor to Set Reference Current Active Inductor and DC Characteristic Adjustment DC Mask Slope Adjustment Analog Ground and Negative Line Voltage Long Line Speech Control Gain Adjustment (GMAX) Short Line Speech Control Gain Adjustment (GMAX - 6dB) Positive Earphone Output Negative Earphone Output Receive Gain Adjustment Switch Mode Power Supply Internal Zener Switch Mode Power Supply Output Ring Start Up Level Ring Power Output Control DTMF Filter 2 Power Ground and Negative Line Voltage Loudspeaker Output
4/57
Zasl VCC Zall VS VL VLS
1 6 4 3 19 15 16
LINE VLS GND 0V
VCC RECIN SNSL SNLL LSSOF VREFL
I.3 - Block Diagram
26
30
TEA7092
VLS/2
VREF ILdc ILdc ILdc I LINE SENSING STATUS
25
VCC/2
IREF
29
I&V REFERENCES
DC CARACTERISTIC
HOLD
LOGIC CTRL
SLPE 31
LSIN AGC AGC INPUTS 200A MUX AGC SAT DETECT
44
ILdc 82.ILac I(vls) LOUDSPEAKER CURRENT SUPPLY & OUT TX ILac+dc Gmax-Gtl DC BIAS
5
REOUT 20 SIDETONE MIXER
GREC 37
MUTE
EAR- 36 DIGITAL VOLUME CONTROL 7 steps 4dB POWER
EARPHONE
VREF
AGC CONTROL VERSUS LINE CURRENT
LSOUT
EARPHONE
AMPLIFIER
EAR+ Gtl -10 -15 -20 -25dB
35
-1
RX & TX
LOUDSPEAKER GND 0V +RING
I - TEA7092 GENERAL INFORMATION (continued)
LOUDHEARING
VLS
38
ASQ 17 ASC 18 dc cut SQUELCH ANTI-HOWLING G=200 MUTE & DTMF AGC ILdc Tx AMP 1/RGT ILac+dc POWER CURRENT EXTRACTOR (3mA)
SOFTL 28
VL
VZP RCO 41 OUTPUT POWER RING SIGNAL OPTIMISATION GND 0V
TSOFT 27
SOFTCLIPPING
MIC2
24
MICRO
MIC1 23
A=10
C21
HFIN 22 SERIAL DC REGULATOR
RING
40 39
HAND-FREE
RSU RING INDICATOR CONTROL ILdc SWITCH MODE POWER SUPPLY SWP
GTR
21
RGT PON & RESET CONTROL I-DAC HF GND 0V
ILL 33
ISL 34
AGND
32
I-DAC LF
LOGIC CONTROL
LOGIC MICROCONTROLLER SERIAL INTERFACE RING MELODY GENERATOR OSCILLATOR GND 0V
DTMF
BEEF MUTE VREF
GND 43
SIDE CODE
GND 0V
7 42
2
8
12
11
14
13
10
9
DTMF1
DTMF2
VMC
VRMC
CLK
RI/VI
OSC VLS 3.58MHz
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
PON RESETN DATA VRMC
5/57
AN848-01.EPS
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
I - TEA7092 GENERAL INFORMATION (continued) I.4 - Input / Output Configurations Figure 1 : VREF (Pin 25) : Transmit and Receive Reference Voltage (VCC/2) VCC (Pin 26) : Transmit and Receive Power Supply IREF (Pin 29) : Internal Reference Current
R11a + R11b From Line
3 VL
R10 VCC + C8
26
The sum of all the currents on Pin 26 (VCC) is equal to 1.3mA (without ac receive signal)
Internal IREF 100k
Ip Internal Amp-op Current Supply 100k
V REF
25
IREF
29
1mA + C14
300mV
Figure 2 :
SLPE (Pin 31) : DC Mask Slope VS (Pin 30) : Shunt Regulator
VL
3
kIL = VCC
IL - 5.6mA 1016 VCC 11A
MIRROR 1 1.5 IL/85 (to transmit channel) IL - 5.6mA 1016 R3 SLPE 31
VCC
R12 VS
50A
30
kIL =
225k
C11
Rslope = R3/55 VL = R12 x (40 + 0.5 x IL) E-6 + Rslope (IL - 5.6) E-3 ; IL in mA (for IL < 20mA) VL = VL (at 20mA) + Rslope x (IL -20) E-3 ; IL in mA (for IL > 20mA)
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AN848-03.EPS
AN848-02.EPS
R2 30k
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
I - TEA7092 GENERAL INFORMATION (continued) I.4 - Input / Output Configurations (continued) Figure 3 : VLS (Pin 1) : Loudspeaker Part Power Supply VMC (Pin 2) : Unregulated Microcontroller Power Supply VRMC (Pin 8) : Stabilized Microcontroller Supply
3 VL
400
10
ITX/41 (see transmit channel)
VLS
1
+ C1
3
ISTART
6V
VL 0.8mA (IL = 4mA) to 3mA (IL > 20mA)
2k
50
Switch ON if : Reset low & KIL
VRMC
8
+ C15
30 to 75A
Info for PON & RESET VMC 2 + C10 470k 6V
AN848-04.EPS
VBANDGAP
Figure 4 :
ILL (Pin 33) : Line Current Regulation Start-up Value ISL (Pin 34) : Line Current Regulation Stop Value
VCC For AGC Control R19 = 300 ISL - 5.6 R18 = 300 ILL - 5.6
300mV
ILL (Pin 33) or ISL (Pin 34) R18 or R19
R18 and R19 in k ; ILL and ISL in mA R18 and R19 should be connected as close to the ground Pin (AGND) as possible.
7/57
AN848-05.EPS
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
I - TEA7092 GENERAL INFORMATION (continued) I.4 - Input / Output Configurations (continued) Figure 5 : TSOFT (Pin 27) : Transmit Softclipping Time Constant SOFTL (Pin 28) : Maximum AC Signal (Softclipping Threshold) MIC1/MIC2 (Pin 23/24) : Microphone Inputs HFIN (Pin 22) : Handsfree Microphone Input DTMF1 (Pin 7) : DTMF Input and Filter DTMF2 (Pin 42) : DTMF Filter GTR (Pin 21) : Transmit Gain Adjustment
10A 20A 20A
VCC 26
SOFTL 28 R1
kVLdc TSOFT 27 kVLacpeak 2.5V C3 5 (Vacpeak + 0.6) x R12 4 40E-6 VREF 25 VREF ITX IL/85 From DC Path LOUDSPEAKER POWER SUPPLY Mirror 1/40 ITX/41 VLS 1 + 2k 18k AGC 0 to -6dB 1 2 C1
3 VL
R1 =
R4
8k
MIC1 23 MIC2 24 20k VREF 25 0dB 20k
To Anti-acoustic Feedback Microphone Choice From Anti-acoustic Feedback (-9dB) Mute
5k
45k
ZB = ZT//CR1//ZL
HFIN 22 0dB 1k VREF 25 R8
21 GTR
0dB 9k EARCMF DTMF2 42 VL (Pin 3) VMIC1 (Pin 23) - VMIC2 (Pin 24)
AN848-06.EPS
10k IDTMF DTMF1 7 Gtl =
= 20 log (820 x
ZB ) R8//50k
8/57
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
I - TEA7092 GENERAL INFORMATION (continued) I.4 - Input / Output Configurations (continued) Figure 6 : SNSL (Pin 15) : Short Line Length Sidetone Network Input SNLL (Pin 16) : Long Line Length Sidetone Network Input RECIN (Pin 19) : Receive Input REOUT (Pin 20) : Receive Output for Handsfree Device GREC (Pin 37) : Receive Gain Adjustment EAR+ (Pin 35) : Positive Earphone Output EAR- (Pin 36) : Negative Earphone Output
ZB RECIN
19
0.6V R11a R11b VL
3
60k
60k
kIL = 0 for IL = ISL kIL = 1 for IL = ILL kIL +6dB Code 0dB 1 - kIL REOUT
20
R27
R13 C12 SNLL
16 15
ITX
ZALL R29+R28//C28
ZASL R5+R6//C5
C27
SNSL ZAL = K x ZALL + (1 - K) x ZASL
26
AGC 21 to 15dB (Code +6dB not activated) R14 GREC
32
VCC VCC 40k
R17
EARCMF
35 EAR+
Mute
10k
Mute
20k
20k
VCC
VREF 25 Mute
36 EARAN848-07.EPS
9/57
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
I - TEA7092 GENERAL INFORMATION (continued) I.4 - Input / Output Configurations (continued) Figure 7 : LSIN (Pin 5) : Loudspeaker Signal Input LSOUT (Pin 44) : Loudspeaker Output VREFL (Pin 4) : LoudspeakerPart Reference Voltage
Ring In RI 10k 20k Volume Control 10k 50k LSOUT 10k
44
LSIN
5
40k LS AGC
DC Translator
+ C2 VLS
1
Vp(LSOUT)
LS
22k + C1 C20
AN848-08.EPS
VREFL
4
VLS/2
22k
10/57
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
I - TEA7092 GENERAL INFORMATION (continued) I.4 - Input / Output Configurations (continued) Figure 8 : ASQ (Pin 17) : Anti-Acoustic Feedback and Squelch Peak Voltage ASC (Pin 18) : Anti-Acoustic Feedback and Squelch Filter LSSOF (Pin 6) : Loudspeaker Softclipping Time Constant
VCC To Transmit AGC 10A From Microphone Preamplifier 60mV VREF 100k 0.5k
0.8k
Attenuation Programmable from 10 to 25dB ASQ 17
R16 C25 ASC 18 VLS
C16
60mV
VREF
25
LS AGC
Vp(LSOUT) GND + 0.2
LSSOF 6
R31 VLS - 0.2 Vp(LSOUT) 4A
C19
AN848-09.EPS
11/57
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
I - TEA7092 GENERAL INFORMATION (continued) I.4 - Input / Output Configurations (continued) Figure 9 : VZP (Pin 38) : Switch Mode Power Supply Internal Zener SWP (Pin 39) : Switch Mode Power Supply Output RSU (Pin 40) : Ring Start-up Level RCO (Pin 41) : Ring Power Output Control
L1 T1 + I(VZP) R37 R35 C6 D2 R36 R32 C30 R38 D3 T2 R33 D7 C1 +
VRING
VZP 38
40 RSU
24V
SWP 39 IVZP Info
VLS 1
VRMC 8 + C15 SERIAL REGULATOR
11.2V 2.6V 5.6V 26kHz LOGIC CONTROL 135k
100A
150k
1.2V VLS > 2.6V RI LOGIC CONTROL VRMC > 2.6V
90k
LSSOF
6
40k
C19
I/17.5k
150k
RI Fi Ring IA = f{(IVZP)} VIN RCO 41 LS AMP LSOUT
44
(VLS - VLSOUT) < 0.2V Gain = 16 + C2
AN848-10.EPS
C4
12/57
R40
R31
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
I - TEA7092 GENERAL INFORMATION (continued) I.4 - Input / Output Configurations (continued) Figure 10 : RI/VI (Pin 10) : Ring Indicator/Line Current Variation
VRMC
Figure 11 : CLK (Pin 13) : Clock Data Input DATA (Pin 14) : Data Input
VRMC VRMC 120k
RI HOLD
INTERNAL LOGIC
AN848-11.EPS
fMax. = 1MHz tMin. between 2 bytes : 2s
Figure 12 : OSC (Pin 9) : Oscillator Input
Figure 13 : RESET (Pin 11) : controller Reset PON (Pin 12) : Power On Output
VRMC
VRMC 300k OSC 9 30pF 30A
Information for PON/RESET INTERNAL LOGIC VRMC IOUT = 1mA max
12 PON
30pF
11 RESET
AN848-13.EPS AN848-14.EPS
13/57
AN848-12.EPS
10 RI/VI IOUT = 1mA max
CLK (Pin 13) or DATA (Pin 14)
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
II - SPEECH FEATURES II.1 - DC Characteristics II.1.1 - TEA7092 DC Voltage The voltage at Pin VL (Pin 3) of the TEA7092 is fixed by 2 external components : - R3 connectedbetween Pin SLPE (Pin 31) and the ground which fixes the DC slope. - R12 connected betweenPin VL (Pin 3) and Pin VS (Pin 30) which fixes the DC voltage at IL = 20mA and a part of the DC slope for IL < 20mA. The voltage at Pin VL (Pin 3) is equal to : For IL < 20mA :
VL = R12 (40 + 0.5 IL) 10 +
-6
Note : At the maximum line current use, the voltage at Pin RECIN (Pin 19) should be less than 11VDC, the following curves stop at the line current where they reach 11VDC at Pin RECIN (Pin 19), depending of the country's application, use this information to optimize the values of R3 and R12. Figure 14
LA
R3 (IL - 5.6)
55
10
-3
VBRI
with IL in mA. For IL > 20mA : VL = VL (20mA) + R3 (IL - 20)
LB
55
10-3
VSWI
with IL in mA, VL (20mA) is the Pin VL (Pin 3) DC value for IL = 20mA. II.1.2 - Telephone Set DC Voltage The telephone set DC voltage at line terminal is equal to (see Figure 14) : V(LA/LB) = VL + (R11a + R11b) x IL + VSWI + VBRI with : - VL : DC voltage on Pin VL (Pin 3) of the TEA7092. - VSWI : voltage across the pulse dialing switch and its protection. - VBRI : voltage across the input rectifier bridge. The Figures 15 to 18 give DC typical value at Pin VL (Pin 3) and at line terminal (LA/LB) for different value of R3 and R12.
R11a
R11b
3
VL VS R12
RECIN
30 19
TEA7092
31
SLPE
AGND
GND
14/57
AN848-15.EPS
32
43
R3
C11
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
II - SPEECH FEATURES (continued) II.1.2 - Telephone Set DC Voltage (continued) Figure 15 : Telephone Set (DC MASK)
14 12 VLA/LB (V) 10 8 6 4 2 0 20 R12 = 68k R12 = 82k R12 = 110k
AN848-16.EPS
Figure 16 : VRECIN (Pin 19)
12 10 VRECIN (V) 8 6 4 2 R12 = 68k R12 = 82k R12 = 110k 0 20 40 60 80 IL (mA) R3 = 2.7k 100 120
40 60 80 IL (mA) R3 = 2.7k
100
120
0
Figure 17 : Telephone Set (DC MASK)
14 12
VLA/LB (V)
Figure 18 : VRECIN (Pin 19)
12 10 VRECIN (V) 8 6 4 2
AN848-18.EPS
10 8 6 4 2 0 20 R12 = 68k R12 = 82k R12 = 110k 40 60 80 IL (mA) R3 = 1.5k 100 120
0
0
20
40 60 80 IL (mA) R3 = 1.5k
100
120
II.1.3 - Start-up Characteristics When TEA7092 goes from iddle state (ON-HOOK) to speech mode (OFF-HOOK) the capacitor C10 connected on Pin VMC (Pin 2) and the capacitor C15 connected on Pin VRMC (Pin 8) are charged in priority, with the main part of the line current. The capacitorC10 is used to supply, through a serial regulator, the microcontroller connected on the regulated 3.5V supply, Pin VRMC (Pin 8). In pulse dialing, flash or earth button mode the capacitor C10 is used to supply the microcontroller, dependingon the power consumption of the microcontroller and on the country's requirements for these different signal durations, it is necessary to adapt the value of C10. Typical capacitor values, with a current consumption of 500A for the microcontroller : C10 = 470F , C15 = 4.7F.
15/57
AN848-19.EPS
R12 = 68k R12 = 82k R12 = 110k
AN848-17.EPS
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
II - SPEECH FEATURES (continued) II.1.3 - Start-up Characteristics (continued) Figure 19 describes the start-up principle. Figure 19
VL R11a + R11b IL RECIN MIC
19 3
TEA7092
400 10
Transmit Amplifier ITX/41
Loudspeaker Current Supply
1
VLS
+ C1
Pins 23 & 24
ON if RESET = 0 & IL Present Istart-up = IVLS 2 50 3mA Serial Regulator
6V VMC
2
+ C10
6V 3.5V
8
VRMC
+ C15
75A Vbandgap RI 21 PON 20 RESET 19 LOGIC BLOCK
AN848-20.EPS
470k
VRMC t
16/57
AN848-21.EPS
When VRMC reaches 2.6V, the Reset goes to high level, the start-up current source is inhibited and only connected to Pin VLS (Pin 1), to power supply the loudspeaker amplifier. The Pin VRMC (Pin 8) reaches its final value, 3.5V by charging the C10 on Pin VMC (Pin 2) and C15 on Pin VRMC (Pin 8) with 3mA current source and finally the voltage on Pin VMC (Pin 2) increases until its final value which is equal to Pin VL (Pin 3) minus 0.4V. Figure 20 gives the start up characteristic timing. When TEA7092 goes from iddle state (ON-HOOK) to ring mode, only the 4.7F capacitor C15 on Pin VRMC (Pin 8) is charged, with Iring current source, and a fast start up delay could be achieved in ring mode.
Figure 20
START-UP VL t VMC t RESET t SPEECH
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
II - SPEECH FEATURES (continued) II.1.4 - Further Information (VCC / VREF / IREF / VMC / VRMC / VLS / VREFL) For more information on these pins see Section I.4 - Input/output Configurations. VCC (Pin 26) , VREF (Pin 25) , IREF (Pin 29) The VCC supplies the transmit path, handset and handfree microphone amplifiers, the receive path, earphone amplifier and the transmit squelch/antiacoustic feedback stage. The current consumption on this pin, I P, is 1.3mA at a 20mA line current (see Figure 21). From the VCC supply, the VREF stage is built. VREF is used as an AC ground for all the stages powered from VCC. The output current compliance of VREF is : 1mA. The reference voltage at VREF is : VCC/2. IREF Pin is used as an internal current reference. The R2 value is fixed and should not be modified. It is recommended to connect a 1% resistor value on this pin. The voltage at IREF pin has a 300mV constant value. Figure 21
100 90 80 70 60 50 40 30 20 10 0 0 10 ILS Ip IVMC 8 6 4 2 0 120
AN848-22.EPS
The DC value at VMC is : VMC = VL - 0.4V and is internally limited at 6V max. VRMC is powered from the highest DC value between Pin VLS (Pin 1) and Pin VMC (Pin 2) in OFF-HOOK state or from Pin VLS (Pin 1) in ring mode. VRMC is a 3.5V stabilized power supply. VRMC supplies the oscillator, the logic part (Microcontroller interface, error beep, and ring frequency generators) and the logic part of the D.A.C. used for the waiting melody and the DTMF generators. The current consumption on this pin is 250A when the oscillator is ON and 50A when the oscillator is OFF code (0111010) is sent. Note : To reduce the C10 value connected at Pin VMC (Pin 2), it is recommended to inhibit the oscillator during the pulse dialing and flash signalizations. In ring mode only the 4.7F capacitor connected on Pin VRMC (Pin 8) is charged to achieve a short delay to generate the ring signal on the loudspeaker. VLS (Pin 1) , VREFL (Pin 4) The VLS supplies the loudspeaker amplifier part. The current source, ILS, between the Pin VL (Pin 3) and the Pin VLS (Pin 1) gives the main part of the line current to supply the loudspeaker amplifier (see Figure 21) : ILS = 0.74 x IL - 1.8mA ; for IL < 15mA ILS = 0.92 x IL - 4.5mA ; for IL > 15mA The internal current consumption on VLS is 1mA, so the current ILS1 available for the loudspeaker and other peripherals is : ILS1 = ILS - 1mA The DC value at VLS depends of the DC value at Pin VL (Pin 3) and is equal to : VLS (Pin 1) = VL(Pin 3) - (0.95 + 10 x ILS) Volts From the VLS supply, the VREFL stage is built. The VREFL is buffered in order to be used as an AC ground for all the stages powered from VLS. The reference voltage at VREFL is : VLS/2.
ILS (mA)
20
40
60 IL (mA)
80
100
VMC (Pin 2) , VRMC (Pin 8) These 2 pins supply the microcontroller. These 2 pins are connected through a serial regulator. On VMC a 470F capacitor is connected, this capacitor is charged only when TEA7092 is powered from Pin VL (Pin 3) (OFF-HOOK state) and is used to power supply the microcontroller during pulse dialing, flash and earth button, when the line loop is open. As described in Section II.1.3, this capacitor is quickly charged during the "Start up" condition.
17/57
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
II - SPEECH FEATURES (continued) II.2 - Impedance Figure 22 : TEA7092 Application Impedance
ILDC + ILAC CR1 R11a R11b
RECIN
19 3
R12
VLDC + VLAC
ZT R10
VL SNLL
16
R13 C27
R27
Rpc
Zsh
30
Cpc
15
ZASL
ZALL
C11
C9
R9
VS
SNSL
C12 R5 R29
TEA7092
31
SLPE AGND
32
26
VCC C28 C5 R6 R28
AN848-23.EPS
Zimp =
VLAC ILAC
C8
R3
ZT
Allows the user to adjust the set impedance by changing the value of R10, R9 and C9 ; In this way the impedance can be adjusted as a real one (only R10) or as a complex one (R10, R9, C9). ZALL Sidetone networks which are in parallel with ZALS ZT, if the ratio : R13/R11a>>1 and R27/(R11a+R11b)>>1, ZALL and ZASL are negligible for the impedance calculation. ZIC Is the internal impedance of TEA7092. It includes the impedance of the transmit path which is equivalent to a current source in parallel with Cpc (3nF), the impedance of all the other stages which are equivalent to Rpc (15k) and the impedance of the shunt regulator stage (AC/DC decoupling stage) made on Pin 30 (VS). TEA7092 application impedance is : Zimp = ZT//ZIC//(ZALL + R11a + R11b) //(ZASL + R11a)//CR1 As it will be describe in Section II.4, the sidetone networks are equal to :
ZALL = R27 (ZT//CR1//ZLL) R11a + R11b R13 ZASL = (ZT//CR1//ZSL) R11a
Figure 23 : Zsh Impedance
AN848-24.EPS
Regulator Shunt Impedance Zsh =
Rslp
Lsh
R3 + (j x 2 x x f x R3 x R12 x C11) 55
Table 1 (RI = 20 log [Zimp + 600] )
[Zimp - 600] Frequency Real Imaginary Module () Phase (Hz) Part () Part () (deg) 200 300 800 1 000 1 500 2 500 3 500 5 000 7 000 9 000 12 000 550 573 604 606 608 606 603 597 589 579 560 80 67 22 12 -5 -28 -43 -67 -94 -119 -154 556 577 605 607 608 607 605 601 596 591 581 8 7 2 1 0 -3 -4 -6 -9 -12 -15 Return Loss [Rl] (dB) 21.7 24.2 34.6 38.8 42.1 32.6 28.8 25 22 19.8 17.3
Figure 24 : Return Loss
40 36 32 RI (dB) 28 24 20 16 12 8 0.1 0.2 0.3 0.5 1 f (kHz) 2 3 5 10 IL = 20mA IL = 100mA Country Limit Request
AN848-25.EPS
Where ZLL is the long line impedance, and ZSL is the short line impedance. If R27/(R11a+R11b) and R13/R11aare higher than 100 (R27 and R13 = 3.3k) :
ZALL and ZASL >> ZT and : Zimp = ZT//ZIC//CR1
Figure 24 and the Table 1 give the TEA7092 application characteristics at IL = 40mA.
18/57
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
II - SPEECH FEATURES (continued) II.3 - Transmit Channel II.3.1 - General Information (Maximum Gain Adjustment) The transmit path amplifies several signals : - The handset microphone. - The handfree microphone. - The DTMF sinewave. - The waiting melody sinewave. At one time, only one of these signals is amplified, the choice is made through the serial bus interconnected with the microcontroller. Figure 25 gives the transmit channel block diagram. Figure 25 : Transmit Channel Block Diagram
IL ZB = ZT//CR1//ZL R11a + R11b C3 RECIN R4
27 19 3
The first switch selects the microphone used. The signal coming from the handset microphone, Pins MIC1 & MIC2 (Pins 23 & 24) is limited by the softclipping stage, more details are given in Section II.3.2 "Softclipping threshold" on this stage. Its gain depends on the gain control stage programming, more details are given in Section II.3.3 "Line loss compensation A.G.C. adjustment". Its absolute value is adjusted on the final stage with Pin GTR (Pin 21). The output signal of the handset microphone preamplifier is used for the squelch feature.
VL
R1
28
TSOFT SOFTL
SOFTCLIPPING STAGE To Loudspeaker Amplifier ITX
R16 C16
17 18
ASQ ASC ANTI-ACOUSTIC FEEDBACK STAGE 0dB 20k 20k Microphone Choice Mute VREF IL/85 from DC Path LOUDSPEAKER CURRENT SOURCE Mirror 1/40 ITX/41 VLS
1
C25 MIC1 23 MIC2 24
5k 45k
+ C1
VREF + C14
25
2k 18k
AGC 0 to -6dB
1
2
HFIN 22 0dB 1k
0dB 9k DTMF2
42
C32 10k DTMF1
7
IDTMF or ISINWAVE
TEA7092
Gtl = 20 log (820 x ZB ) R8//50k VREF
25 21
C13
R8
GTR
19/57
AN848-26.EPS
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
II - SPEECH FEATURES (continued) II.3 - Transmit Channel (continued) Figure 26 : Softclipping Stage
MIC1 Microphone Preamplifier
23 24
TEA7092
REST OF THE TRANSMIT CHANNEL 20A
3 VL
MIC2
20k
20k
VCC VL(DC) - VL(ACp) VL(DC) - 2.5V 20A VCC 10A kVL(ACp) VCC
U/I Converter
25
27
28
VREF + C14 C3
TSOFT
SOFTL
AN848-27.EPS
R4
R1
The second switch selects the microphone signal, the mute mode, the DTMF mode or the sinewave mode (waiting frequency). The maximum transmit gain, Gtl is fixed by R8 connected on Pin GTR (Pin 21) and is equal, on Pin VL (Pin 3) to :
ZT//CR1//ZL + (R11a + R11b) Gtl = 20 log 820 R8//50k
pared to 2.5VDC. This limitation is useful for low line current when the DC level at Pin VL (Pin 3) is low. This limitation is useful when two telephone sets are off-hook in parallel on the same line. On an absolute line level, this level is fixed by R1 connected on Pin SOFTL (Pin 28) and depends on R12 value : Vacpeak = (5 x R12 - 4 x R1) x 10-5 - 0.6 Figure 26 describes the sofclipping stage. Figure 27 gives an example of the VACPEAK transmit level versus line current for R12 = 82k and R1 = 47k. Figure 27
10 VL (V) (Pin 3) 8 1.6VP 6 4
AN848-28.EPS
Zimp is the complete telephone set application and ZL is the line impedance. 50k is the value of the integrated resistor connected between the Pin GTR (Pin 21) and the Pin VREF (Pin 25). If it is necessary, to have a steady gain over the frequency range 300Hz to 3.4kHz, R8 can be replaced by a complex network : R8 + R7//C7. The final amplifier stage is the louspeaker current source supply, which is modulated by the transmit signal, therefore no significatif line current is used for the transmit path, and the current source supply for the loudspeaker part versus the line current is always optimized. II.3.2- Softclipping Threshold (Maximum Line Level) The softclipping stage limits the transmit level on line. This level is limited in two ways : The transmit negative part of the sinewave is com-
.5 0
0.9VP 20 40 60 IL (mA) 80 100
20/57
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
II - SPEECH FEATURES (continued) II.3 - Transmit Channel (continued) Figure 28 g ives the t ransmit line level at Pin VL (Pin 3) and the transmit distortion versus the input microphone level (Pin MIC1 (Pin 23) & Pin MIC2 (Pin 24)) for R12 = 82k, R1 = 47k & R8 = 1.62k. Figure 28 : Tx Output Level & Distortion (IL=20mA)
2 1 VLA/LB (Vrms) 0.5 0.2 0.1 0.05 0.2 0.5 1 2 VMIC 5 10 (mVRMS) 20 VLINE Distortion 12 10 D[VLA/LB] (%) 8 6 4 2 0 50 100
AN848-29.EPS
transmit and receive gains are equal to the maximum gain value minus 6dB. 300 in k ; ISL in mA R19 = ISL - 5.6 For line current values lower than ILL, the transmit and receive gains stay at their maximum values. For line current values upper than ISL, the transmit and receive gains stay at their minimum values. Figure 30 gives A.G.C. with a constant start value (IL = 20mA) and different values of R19. Figure 31 gives A.G.C. with a constant stop value (IL = 100mA) and different values of R18. Figure 30 : dGtx = f(IL)
0 R19 = 8.2k R19 = 6.8k R19 = 4.7k R19 = 3.9k R19 = 3.3k
Figure 29 gives the maximum transmit level at Pin VL (Pin 3) versus R1, for R3 = 2.7k & for different values of R12, at IL = 40mA. Figure 29 : Vac Max On Line
3.25 3 2.75 2.5 2.25 2 1.75 1.5 1.25 1 0.75 0.5 0.25 0 R12 = 68k R12 = 82k R12 = 110k
dGtx (dB)
-2
-4
0
20
40 60 IL (mA)
80
100
VLA/LB (V)
Figure 31 : dGtx = f(IL)
0
0
20
40
60 R1 (k)
80
100
120
dGtx (dB)
AN848-30.EPS
-2 R18 = 18k R18 = 10k R18 = 8.2k R18 = 6.8k R18 = 5.6k 0 20 40 60 IL (mA) 80 100
-4
II.3.3 - Line Loss Compensation/ A.G.C. Adjustment The TEA7092 uses a line current information to control the transmit and receive gains variation versus the line current. TheAutomaticGainControl(A.G.C.)versus linelength works in the same way for transmit and receive paths. Through two external resistors the line current variation, where the A.G.C. occurs, is programmable : - R18 connected on Pin ILL (Pin 33) sets up the start up line current value, ILL, for the A.G.C. 300 R18 = in k ; ILL in mA ILL - 5.6 - R19 connected on Pin ISL (Pin 34) sets up the slope and the line current value, I SL, where the
II.3.4 - A.G.C. Inhibition The A.G.C. feature can be inhibited through the serial bus interface by sending the code 0010100. This code is a toggle one. When the no A.G.C. mode is selected the transmit and receive gains stay at their maximum values -2dB over the line current range variation. This feature is used for a telephone set connected behind a PABX or in a country where the A.G.C. feature is not requested.
21/57
AN848-32.EPS
-6
AN848-31.EPS
-6
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
II - SPEECH FEATURES (continued) II.3.5 - Transmit Squelch / Antiacoustic Feedback Stage Figure 32 : Block Diagram
TEA7092
From Microphone Preamplifier V CC 60mV 100k 0.5k 60mV
18
10A To Transmit AGC 0.8k VREF LS AGC
ASC
V REF
25
17
ASQ
AN848-33.EPS
R16 C25 C16
Figure 33
Gtx (dB) Gmax Gmax - 9.5dB 3dB
* 60mV at Pin 17
Low Microphone Level *
Normal Speech
High Microphone Signal Softclipping Mode
9dB
Vsl
Vst
Vsoft
GLS is Programmable through the Volume Control Stage x is Programmable through the Serial Bus (10, 15, 20, 25dB) (default value is 15dB)
VMIC
GLS GLS - xdB
VMIC
-80
-76
-72
-68
-64
-60
-56
VMIC (dBV) (Pins 23 & 24)
22/57
AN848-35.EPS
The same stage is used for the transmit squelch and the antiacoustic feedback feature which is used in loudspeaking mode. Figure 32 shows the block diagram of this stage. When there is no signal on the handset microphone inputs, the transmit gain is reduced by 9dB, refer to the maximum gain, and the loudspeaker amplifier is at the gain value set by the volume control stage, (see Section III - CALL PROGRESS MONITOR AND GROUP LISTENING MODES). When the handset microphone signal is present and increases progressively, it describes the first curve in Figure 33 and the loudspeaker amplifier describes the second curve in Figure 33. The attenuationof the loudspeaker amplifier for the antiacoustic feature is programmable from 10dB to 25dB through the serial bus interface, the default value is 15dB. The squelch thresholdfeature can be inhibited through the serial bus interface by sending the code (0011001) without affectingthe antiacousticfeedback control. This code is a toggle one. The squelch threshold level
is adjustable through the C25 capacitor value connected at Pin ASQ (Pin 18). Be aware that when the threshold level is modified, the cut-off frequency of the filter is also modified. The squelch threshold level is determined by the microphone level injected at Pins MIC1 & MIC2 (Pins 23 & 24). Figure 34 gives the threshold level with a maximum transmit gain of 44dB. Figure 34 : SquelchThreshold (IL = 20mA/fMIC = 1kHz)
44 42 Gtl (dB) 40 38 36 C25 = 100nF C25 = 470nF C25 = 1F
AN848-34.EPS
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
II - SPEECH FEATURES (continued) II.4 - Sidetone II.4.1 - General Information The sidetone uses the wheatstone bridge principle (see Figure 35). Figure 36 shows the block diagram of the sidetone stage. TEA7092 integrates a line tracking sidetone network which uses two sidetone networks. One sidetone network, ZALL, is optimized for a long line length connection and the other one, ZASL, is optimized for a short line length connection. An internal mixer stage uses a line current information, kIL, to smooth linearely from ZALL to ZASL with the following equation : ZAL = k x ZALL + (1 - k) x ZASL Figure 35
RECIN
TEA7092
k = 1 for IL = ILL, k = 0 for IL = ISL and k varied linearly between 1 and 0 when the line current varied from ILL to ISL. Like this, the sidetone is optimized for every line length. This concept can be suppressed by shortcircuiting the two sidetone inputs, Pin SNLL (Pin 16) and Pin SNSL (Pin 15) and to connect only one sidetone network, in this case the sidetone is only optimized for one line length, as a standard one, and the efficiency of the sidetone is lower on all the other line length connections.
V1 IL
Rx
VL
V1 - V2 Ry SN
To Earphone
ITX ZB = ZT//CR1//ZL
TEA7092A
ZAL V2
Figure 36
RECIN ZBL or ZBS R11a R11b 60k 60k VL kIL = 0 for IL = ISL kIL = 1 for IL = ILL kIL +6dB Code 0dB 1 - kIL AGC 21 to 15dB (Code +6dB not activated)
20 REOUT 19
TEA7092
0.6V
3
ITX R27 R13 C27 SNLL
16 15
ZALL R29+R28//C28
ZASL R5+R6//C5
C12 SNSL ZAL = K x ZALL + (1 - K) x ZASL VCC +
26
C8
23/57
AN848-37.EPS
AN848-36.EPS
V1 = V2 if ZAL =
Ry x ZB Rx
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
II - SPEECH FEATURES (continued) II.4.2 - One Sidetone Network Principle Figure 37 gives the sidetone connection. Figure 37
RECIN
19
TEA7092
0.6V
ZB
R11 60k 60k VL kIL = 0 for IL = ISL kIL = 1 for IL = ILL kIL +6dB Code 0dB 1 - kIL AGC 21 to 15dB (Code +6dB not activated)
20 REOUT
3
R13 SNLL
16 15
ITX
ZASL R5+R6//C5
C12 SNSL ZAL = K x ZALL + (1 - K) x ZASL VCC +
26
C8
The sidetone is optimized if : V1 - V2 = VRECIN(19) - VSNSL/SNLL (15/16) = 0 R27 ZB ZAL =
R11
With ZB = ZT//CR1//ZL. Figure 38 gives the sidetone efficiency versus the line length. Figure 38
Vear High
AN848-39.EPS
If, R27 = K1 x R11 and K1 >> 1 : V1 - V2 R11 Gsid = = v1 R11 + ZB Thesidetoneattenuationis proportionalto R11andZB. II.4.3 - Line Tracking Sidetone Principle Figure 39 gives the sidetone connection. The sidetone are optimized if : V1 - V2 = 0 - On long line connection : V1 - V2 = VRECIN (19) - VSNLL (16) = 0 R27 ZBL ZALL = R11a + R11b with ZBL = ZT//CR1//ZLL. - On short line connection : V1 - V2 = VRECIN (19) - VSNSL (15) = 0 R13 ZBS ZASL =
Low 0 1 2 3 4 Line (Km)
R11a
In receive mode the signal V1-V2 is amplified through the receive path. The attenuationdue to the external components of the sidetone stage is : V1 - V2 R11 + R27 Gsid = = R11 + R27 + ZAL v1
with ZBS = ZT//CR1//ZSL. ZLL is the long line length impedance and ZSL is the short line length impedance. Figure 40 gives the sidetone efficiency versus the line length for a one sidetone network principle and a tracking sidetone network principle.
24/57
AN848-38.EPS
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
II - SPEECH FEATURES (continued) II.4 - Sidetone (continued) Figure 39
19
TEA7092
0.6V
60k
VL
3
ITX R27 R13 C27 SNLL
16 15
60k
ZBL or ZBS
R11a R11b
RECIN
kIL = 0 for I L = ISL kIL = 1 for I L = ILL kIL +6dB Code 0dB 1 - kIL AGC 21 to 15dB (Code +6dB not activated)
20
REOUT
ZALL R29+R28//C28
ZASL R5+R6//C5 + C8
C12 SNSL ZAL = K x ZALL + (1 - K) x ZASL VCC
26
Figure 40
Vear High One Sidetone Network
AN848-41.EPS
Tracking Sidetone Low 0 1 2 3 4 Line (Km)
In receive mode the signal V1-V2 is amplified through the receive path. The attenuationdue to the external components of the sidetone stages are : - For a line current equivalent to a long line connection : R11a + R11b + R27 V1 - V2 = Gsid(l) = V1 R11a + R11b + R27 + ZALL If, R27 = K1 x (R11a + R11b) and K1 >> 1 : R11a + R11b V1 - V2 = Gsid(l) = V1 R11a + R11b + ZBL The sidetone attenuation is proportional to (R11a + R11b) and ZBL. - For a line current equivalent to a short line connection : R11a + R13 V1 - V2 = Gsid(s) = V1 R11a + R13 + ZASL If, R13 = K1 x R11a and K1 >> 1 : R11a V1 - V2 = Gsid(s) = V1 R11a + ZBS The sidetone attenuation is proportionnal to R11a and ZBS.
R11a and R11b should be calculated to have the same attenuation due to the two sidetone networks. In this way the complete receive channel gain is fixed on Pin GREC (Pin 43) and in A.G.C. mode the receive gain is reduced by 6dB between ILL, line current for a long line connection, and ISL , line current for a short line connection. If an application requests less or more than 6dB on the complete receive channel,the values of R11a and R11b will be adapted to it. II.4.4 - Sidetone Programmating for PABX Application When the tracking sidetone network is used, it is possible to inhibit it through the serial bus interface. This principle suppresses the switches existing in a telephone set, when this one can be indifferently connected to a public exchange or a private exchange. When it is connected on a publicexchange the tracking sidetone network is used. When it is connected on a private exchange the tracking sidetone network is inhibited, internally the kIL information which controls the sidetone mixer stage is fixed independently of the line current value, and can take two values : - By sending the code 0011000, the sidetone network is equivalent to :
ZAL = 3 1 ZALL + ZASL 4 4
- By sending the code 0011011, the sidetone network is equivalent to : ZAL = ZASL
25/57
AN848-40.EPS
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
II - SPEECH FEATURES (continued) II.5 - Receive Channel II.5.1 - General Information (Maximum Gain Adjustment) The receive path amplifies several signals : The signal VRECIN - VSNLL or VRECIN - VSNSL or a combination of both is amplified to the ear- The line signal to the earphone with an intermephone outputs. diate output, Pin REOUT (Pin 20) so as to use this signal as an input for the loudspeaker ampliAs described in Section II.4.2 and Section II.4.3 the fier or for a handfree circuit such as TEA7540. signal V1 is attenuated through the sidetone net- The DTMF sinewave as a confidence tone level. work. After this attenuation, the received signal is - The waiting melody sinewave as an earphone amplified by the Sidetone mixer and A.G.C. stages level control. with an amplification, of 21dB on a long line length, At one time, only one of these signals is amplified, ILL, which is the maximum receive gain, and of the choice is made through the serial bus interface 15dB on a short line length, ISL , when the A.G.C. with the microcontroller. feature is used. The final gain adjustment is done Figure 41 shows the receive channel block diagram. Figure 41
REOUT IL RECIN
20 19
on Pin GREC (Pin 20) by adjusting R14 and R17 values.
TEA7092
0.6V R14
32
R11a VL 60k 60k R11b Sidetone Mixer & AGC Stages VCC
GREC
R17
A2 R27 R13 C12 ZALL R29+R28//C28 SNLL
16 15
35
EAR+
21 to 15dB 40k Mute VREF C14 20k
26
ZASL R5+R6//C5
C27
SNSL
25
A1 VCC 20k VCC
10k Vear Idtmf or Isinwave
36
+ C8 A3 EAR-
DTMF C13
Mute
26/57
AN848-42.EPS
37
Mute
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
II - SPEECH FEATURES (continued) II.5 - Receive Channel (continued) The gain between Pin RECIN (Pin 19) and the earphone outputs, Pin EAR+ (Pin 35) and Pin EAR- (Pin 36) is : - With tracking sidetone and A.G.C. features, earphone connected in symmetric mode : * On long line, I L = ILL, maximum gain Vear Grl(dB) = 20 log VL R17 = 20 log(Gsid(l)) + 21dB + 20 log2 R14 * On short line, IL = ISL, minimum gain Vear Grs(dB) = 20 log VL R17 = 20 log(Gsid(s)) + 15dB + 20 log2 R14 - With One sidetone network and A.G.C. features, earphone connected in symmetric mode : * On long line, I L = ILL, maximum gain Vear Grl1(dB) = 20 log VL R17 = 20 log(Gsid) + 21dB + 20 log2 R14 * On short line, IL = ISL, minimum gain Grsl(dB) = Grl1 - 6dB Figure 42 shows the asymmetric connection. Note : Due to the concept used to power supply the earphone through the impedance network (R10) and with the VCC supply, it is preferable to connect the earphone in asymmetric mode if the earphone impedance is less than 300, and in symmetric mode if the earphone impedance is more than 300. More details are given in the following paragraph. II.5.2 - Maximum Output Level The maximum output level depends on several parameters : - The DC level on Pin VL (Pin 3). - The impedance network value connected between Pin RECIN (Pin 19) and Pin VCC (Pin 26). - The earphone impedance value. Figure 43 shows the earphone amplifier supply principle. Without AC signal the voltage at Pin VCC (Pin 26) is : VCC = VL + R11a/b x IL - (R10 + R11a/b) x IP The value at Pin VL (Pin 3) depends on R12 (see Section II.1.1). When an ac signal is amplified, the current driving the earphone, Iear, flows through R10 and the DC voltage at Pin VCC (Pin 26) is reduced.
It is possible to use only one output, asymmetric mode, in this case all the receive gain are reduced by 6dB. Figure 42
TEA7092
RECEIVE AMPLIFIER A3 -1
26
VCC + C8
From Sidetone Mixer VREF REOUT
20 37
A2
36 EAR-
GREC R17
35
EAR+
AN848-43.EPS
R14
+ C24
Earphone
27/57
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
II - SPEECH FEATURES (continued) II.5 - Receive Channel (continued) Figure 43
IL - (Ip + Iear) IL R11a/b VL
3
VL (3) R12 VS
30
C11
Iear RECIN
19
EAR+ C24
35
Ip + Iear
R10
26
Iear Ip -1
36
AN848-44.EPS
+ C8
VCC
TEA7092
EARRear Symmetric or Asymmetric Use
With this principle the maximum output voltage at Pin EAR+ (Pin 35) and Pin EAR- (Pin 36), dependingon the application, is limited in current and in voltage in the following way : R11 = R11a + R11b IP = 1.3mA at IL = 20mA IP = 1.7mA at IL = 60mA (see Figure 21). VRECIN = VL(3) + R11 x (IL - IP - IEAR) and VCC = VRECIN - R10 x (IP + IEAR) - In asymmetric use; Earphone (REAR) connected on Pin EAR+ (Pin 35). VCC = 2 x VEAR(peak)(Max.) + 0.4 VEAR(RMS) = VEAR(RMS) (Max.) in VRMS : VEAR(RMS) (Max.) = REAR IEAR 2
REAR [VL + R11 IL - (R10 + R11) IP - 0.4] (2 REAR + R10 + R11) 2 - In symmetric use; Earphone (REAR) connected between Pin EAR+ (Pin 35) & Pin EAR- (Pin 36). VCC = VEAR (peak)(Max.) + 0.2 VEAR(RMS) = VEAR(RMS) (Max.) in VRMS : VEAR(RMS) (Max.) = REAR IEAR 2 2
REAR [VL + R11 IL - (R10 + R11) IP - 0.2] 2 ( REAR + 2 (R10 + R11))
Notes : 1. In few applications, at low line current (IL < 20mA) and depending on the DC voltage at Pin VL (Pin 3), the absolute minimum value of VCC, 2V, should be taken into account in the calculation of VEAR(RMS)(Max.). This limitation happens if : IL = 20mA, R12 = 68k and R10 = 1200 (complex impedance DC value). 2. Usually, when the impedance of a transducer, Rear, increases, the efficiency of the transducer in dBSPL/V decreases. The receive gain is adapted to the earphone impedance to offset this transducer'sefficiency change, so that the complete acoustical gain of the receive path remains constant.
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TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
II - SPEECH FEATURES (continued) II.5 - Receive Channel (continued) Table 2
Asymmetric R17 C17 REAR = 150 33k 680pF REAR = 300 68kW 330pF REAR = 600 68k 330pF Symmetric REAR = 1k 120k 220pF
The Table 3 gives the value of VEAR(RMS)(Max.), at IL = 20mA & IL = 60mA, for different values of, R12 (68k, 82k, 110k), R10 (680, 1200 to simulate a complex impedance), REAR (150, 300 in asymmetric mode ; 600, 1k in symmetric mode) and a distortion level at 2% and 10%. Table 3
IL R10 R12 68k 680 82k 110k 68k 1200 82k 110k 68k 680 82k 110k 68k 1200 82k 110k D (%) 2 10 2 10 2 10 2 10 2 10 2 10 2 10 2 10 2 10 2 10 2 10 2 10 150 (A) 0.45 0.51 0.45 0.51 0.46 0.51 0.26 0.29 0.39 0.42 0.46 0.5 0.28 0.32 0.28 0.32 0.29 0.32 0.28 0.32 0.28 0.32 0.29 0.33 Earphone Output Level (VRMS) 300 (A) 600 (S) 1k 0.77 1.2 0.85 1.3 1.6 0.9 1.4 0.96 1.52 1.92 0.98 1.91 1.1 2 2.56 0.52 0.59 0.57 0.61 0.97 0.64 0.87 0.69 0.89 1.33 0.89 1.32 0.95 1.37 1.8 0.6 1.2 0.69 1.4 2.5 0.6 1.25 0.69 1.42 2.5 0.62 1.27 0.7 1.44 2.6 0.6 1.23 0.69 1.4 1.98 0.6 1.25 0.69 1.33 2.3 0.62 1.28 0.7 1.45 2.6 (S) 1.5 1.8 2.4 0.95 1.25 1.65 2.3 2.3 2.3 1.9 2.15 2.3
20mA
60mA
The sidetone mixer stage has a limiter to avoid acoustic signal higher than 120 dBSPL on the earphone. Example : Electrodynamic transducer : 150 / 122 dBSPL/V - R10 = 680 ; * At IL = 20mA : VEAR(Max.) = 0.51VRMS 116.2 dBSPL * At IL = 60mA : VEAR(Max.) = 0.33VRMS 112.4 dBSPL If this acoustic limitation is too low, it is possible to modify it by : - Decreasing the gain of the sidetone attenuation = Decrease R11a & R11b. (R13 & R27 should also be modified). - Increasing the gain on Pin GREC (Pin 37), to maintain the same total receiving gain Increase R17.
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TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
II - SPEECH FEATURES (continued) II.5.3 - Line Loss Compensation / A.G.C. Adjustment The characteristics of the A.G.C. stage in the receive path are the same as those in the transmit path. For more information see Section II.3.3. II.5.4 - A.G.C. Inhibition The characteristics of the A.G.C. inhibition stage in the receive path are the same as those in the transmit path. For more information see Section II.3.4. II.5.5 - +6dB Mode Through the serial bus interface, it is possible to Figure 44 increase the receive gain amplifier by 6dB. This code (0010110) is a toggle code. II.6 - Handsfree Interface Figure 44 shows the interconnection between TEA7092 and Handsfree circuit such as TEA7540. TEA7092 should be in Handsfree mode (0110010). The Handsfree circuit is supplied through the Pin VLS (Pin 1) I n t h is mod e t he sig n a l inje c t e d on Pin HFIN (Pin 22) is amplified, the antiacoustic feedback stage is inhibited and the loudspeaker amplifier is activated. The receive path of the Handsfreecircuit is inserted between Pin REOUT (Pin 20) and Pin LSIN (Pin 5).
TEA7092
43 GND
LSOUT 6 VLS 1 L
HFIN REOUT LSIN
22 20 5
3
15
26
OUTE GND 1
13 INE
INR
OUTR V+ 28
Handfree Microphone
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AN848-45.EPS
TEA7540
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
III - CALL PROGRESS MONITOR AND GROUP LISTENING MODES III.1 - General Information The Call Progress Monitor and Group Listening modes are OFF-HOOK modes with the loudspeaker being used. The Call Progress Monitor, or "ON-HOOK dialing" is an OFF-HOOK mode where the line is taken through a dedicated key which closes the line without using the handset. In this mode only the loudspeaker is enabled, to hear the different tones coming from the exchange. As soon as the handset is off-hook the loudspeaker is disabled and no longer used. In Call Progress Monitor, the handset microphone is muted and the anti-acoustic feature is disabled. The group listening mode is an OFF-HOOK mode where the handset and the loudspeaker are simultaneously used. The receive signal can be heard in the earphone and in the loudspeaker. In Group listening mode, the anti-acoustic or anti-howling feature is enabledto prevent any feedbackfrom the handset microphone to the loudspeaker which can cause howling effect. Figure 45 shows the loudspeaker amplifier path. The signal coming from Pin REOUT (Pin 20), intermediate receive output, is injected into the loudspeaker amplifier on Pin LSIN (Pin 5). Between pin Figure 45
Ring in RI 10k 20k Volume Control SIN 5 40k LS AGC 10k DC Translator 10k 50k LSOUT
44
REOUT (Pin 20) and Pin LSIN (Pin 5) a filter can be added to offset the loudspeaker frequency response curve. The loudpeaker is connected on Pin LSOUT (Pin 44). The maximum gain between Pin LSIN (Pin 5) and Pin LSOUT (Pin 44) is 34dB. When a handsfree circuit is used, its receive path is connected between Pin REOUT (Pin 20) and Pin LSIN (Pin 5). The loudspeaker amplifier, as described in Figure 45, is controlled by the following signals : - LS AGC from the anti-acoustic feedback stage which attenuates the loudspeaker amplifier gain when the handset microphone level goes upper the threshold to avoid howling effect. - Pin LSSOFT (Pin 6) which attenuates the loudspeaker amplifier gain, to drive properly the loudspeaker when the LSOUT output reaches the saturation of the output stage compared to VLS or the ground, through VPP(LSOUT) information. This information acts as a softclipping stage, so the gain is reduced without any distortion. - The volume control stage adjusts, by 4dB step, the loudspeaker amplifier gain, with a maximum depth of 28dB. Note : In default mode, the gain of the volume control stage is egal to Gmax -28dB.
+ C2 L
AN848-46.EPS
TEA7092
Vp(LSOUT)
31/57
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
III - CALL PROGRESS MONITOR AND GROUP LISTENING MODES (continued) Figure 46
IL VL
3
TEA7092
400 10
ITX/41 (See Transmit Channel)
Switch Close, if RESET Low and IL Present Istart-up
1
2
AN848-47.EPS
VLS + C1
VMC + C10
III.2 - Loudspeaking Part Supply T h e lo u d s pe a kin g pa rt is p o we red on Pin VLS (Pin 1). The final stage of the transmit path is simultaneously used to amplify the transmit signal and to power supply the loudspeaking part. Figure 46 shows the loudspeaking part supply. After an OFF-HOOK action, during the start-up period and still the microcontroller reset is low, the current power supply of the loudspeaking part is used to charge quickly the capacitor C10 on pin VMC (Pin 2), capacitor which is used to power supply the microcontroller. Figure 47 shows the line current, IL, partition in the different paths of the TEA7092. - ILS : Current available for the loudspeaker part and other peripherals.
- IVMC : Current for the microcontroller power supply. - IVCC : Speech part current consumption. Other peripherals like a handsfree circuit or discret CMOS logic can be powered on Pin VLS (Pin 1). Figure 47
100 90 80 70 60 50 40 30 20 10 0 0 10 ILS IP IVMC 8 IP /VMC (mA
AN848-48.EPS
ILS (mA)
6 4 2 0 120
20
40
60 IL (mA)
80
100
32/57
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
III - CALL PROGRESS MONITOR AND GROUP LISTENING MODES (continued) III.3 - Softclipping Stage The softclippingstage avoids distortion on the loudspeaker output LSOUT (Pin 44) over a range of input signals on Pin LSIN (Pin 5). Figure 48 shows the loudspeaker softclipping stage. The softclipping stage avoids distortion when there is n o t e n ou g h DC s u p ply vo lt a g e on Pin VLS (Pin 1). This is done by detecting the saturation on the Pin LSOUT (Pin 44) compared to Pin VLS (Pin 1) - 0.2V and GND + 0.2V. When one of these two voltages is reached, the DC voltage on Pin LSSOF (Pin 6) increases and the loudspeaker amplifier gain is reduced through the VPP(LSOUT) signal control. III.4 - Antiacoustic Feedback Features The same stage is used to control the antiacoustic feedback stage, to avoid howling effect, than to control the squelch stage. Figure 49 shows the antiacoustic feedback and squelch stage. In group listening mode, when the handset and the loudspeaker are simultaneously used, it is neccessary to avoid howling effect between the handset microphone and the loudspeaker. The antiacousticfeedback stage detects the microphone signal and, if this one is higher than the fixed threshold (60mV), the gain of the loudspeaker is Figure 48
TEA7092
VLS LS AGC
reduced through LS AGC information. By default the loudspeaker amplifier gain reduction is fixed at 15dB, this one can be modified through the serial bus interface with the following values : - 10dB : code (0111100). - 15dB : code (0111101), equivalent to default mode. - 20dB : code (0111110). - 25dB : code (0111111). These different values allow the adaption of the antiacoustic feedback stage to different telephone sets. Figure 50 shows the behaviour of the antiacoustic feedback stage (coupled with the squelch feature, if this one is enabled). The signal microphone is amplified by the first stage with a gain close to 200, and filtering on Pin ASC (Pin 18), the cut off frequency is fixed by C25 and the internal 0.5k. Recommended values : C25 = 470nF or 1F fC = 677Hz or 318Hz On Pin ASQ (Pin 17), the rise and decay times are fixed by R16, C16 and the 10A internal current source. C16 x 60 x 10-3 - Rise time : tR = , 10 x 10-6 with C16 = 1F tR = 6ms. - Decay time : tD = R16 x C16, with R16 = 330k andC16 = 1.5F tD =330ms.
Vp(LSOUT) GND + 0.2
VLS - 0.2 Vp(LSOUT)
4A
6
LSSOF
R31
C19
AN848-49.EPS
33/57
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
III - CALL PROGRESS MONITOR AND GROUP LISTENING MODES (continued) III.4 - Antiacoustic Feedback Feature (continued) Figure 49
TEA7092
10A From Microphone Preamplifier 60mV 100k 0.5k VREF 0.8k Attenuation Programmable from 10 to 25dB LS AGC VCC To Transmit AGC
60mV VREF
18 25 17
ASC C25
VREF R16
ASQ
C16
Figure 50
Gtx (dB) Gmax Gmax - 9.5dB 3dB Vsl
* 60mV at Pin 17
Low Microphone Level *
Normal Speech
High Microphone Signal Softclipping Mode
9dB
Vst
Vsoft GLS is Programmable through the Volume Control Stage
VMIC
GLS GLS - xdB
VMIC
34/57
AN848-51.EPS
x is Programmable through the Serial Bus (10, 15, 20, 25dB) (default value is 15dB)
AN848-50.EPS
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
III - CALL PROGRESS MONITOR AND GROUP LISTENING MODES (continued) III.5 - Maximum Output Power The loudspeaker part is powered through the Pin VLS (Pin 1). The VLS power could come from the line, Pin VL (Pin 3) or an external power supply, +5V for example. When it is powered from the line, Pin VL (Pin 3), the available current, ILS an d t h e v olt a ge at Pin VLS (Pin 1) depend on the line current IL. - VLS (Pin 1) = VL (Pin 3) - (0.95 + 10 x ILS) - ILS = 0.74 x IL - 1.8mA ; if IL < 15mA - ILS = 0.92 x IL - 4.5mA ; if IL > 15mA The current consumption of the loudspeaker amplifier is 1mA, so the current available for the loudspeaker is : ILS1 = ILS - 1mA Figures 51, 52 and 53 give the maximum power available on the loudspeaker for different loudspeaker impedances (25, 32, 50) and different values of R12 (R12 sets up the DC voltage at Pin VL (P in 3) an d t h e DC v o lt ag e a t Pin VLS (Pin 1), thus it has an influence on the maximum power available on the loudspeaker). Figure 51 : Output Power On LSOUT
100 90 80 70 60 50 40 30 20 10 0 0 LS = 25 LS = 32 LS = 50 P (mW)
When there is enough line current to drive properly the charge on the loudspeaker output, the maximum peak to peak dynamic is : - On Rloudspeaker = 25 : VPP = VLS - 1.1V - On Rloudspeaker = 32 : VPP = VLS - 1V - On Rloudspeaker = 50 : VPP = VLS - 0.9V Figure 52 : Output Power On LSOUT
100 90 80 70 60 50 40 30 20 10 0 0 LS = 25 LS = 32 LS = 50
P (mW)
10 20 30
40 50 60 70 80 90 100 110
IL (mA) (R12 = 82k)
Figure 53 : Output Power On LSOUT
130 120 110 100 90 80 70 60 50 40 30 20 10 0 0 LS = 25 LS = 32 LS = 50
P (mW)
AN848-52.EPS
10 20 30
40 50 60 70 80 90 100 110
10 20 30
40 50 60 70 80 90 100 110
IL (mA) (R12 = 68k)
IL (mA) (R12 = 110k)
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AN848-54.EPS
AN848-53.EPS
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
III - CALL PROGRESS MONITOR AND GROUP LISTENING MODES (continued) III.6 - External Power Supply Facility Figure 54
TELEPHONE SET
LINE LA LB
LINE INTERFACE - EHKS Interface - Pulse Dialing Interface - RC Ring Interface DP HKS
KEYBOARD
VRING LS EAR MIC
TEA7092 Application
HFIN REOUT LSIN VLS 1 2 3 4
VRMC
VSPEECH RESET DATA CLK PON RI
TKL EHKS
MICROCONTROLLER 1 Application
SW1
SW2
ANSWERING MACHINE
RECORDER
+5V
MICROCONTROLLER 2
AN848-55.EPS
MAIN
MAIN POWER ISOLATION AND SUPPLIES
The loudspeaker amplifier can be powered through an external power supply, such as a +5V one. This external power supply facility allows the use of TEA7092 in a terminal such as an answering machine, a cordless or others, with a direct interface with the +5V external power supply. Figure 54 shows how to connect the TEA7092 in an answering machine. The different inputs/outputs are : - Line Interface : * LA/LB : line wire terminal - Line Interface / TEA7092 : * VRING : TEA7092 supply in ring mode * VSPEECH : TEA7092 supply in OFF-HOOK mode - Line Interface / Microcontoller 1 : * DP : Pulse interface control * HKS : Hook switch information * EHKS : On-hookdialing or handsfreeinformation * TKL : P line seizure feedback in EHKS mode - TEA7092 / Microcontroller 1 / 2 : * RESET * PON : Line current presence * RI : Ring information * DATA / CLK : Serial bus interface
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- TEA7092 / Answering Machine : * 1) Outgoing message registration ; The line is open, TEA7092 is powered from the +5V and the switch SW1 is closed. * 2) Outgoing message is sent to the line ; TEA7092 is powered from the line and the o u t g o in g m es sa g e is s e nt o n Pin HFIN (Pin 22), amplified through TEA7092 and sent to the line. * 3) Incoming message registration ; TEA7092 is powered from the line and the incoming message is sent to the answering machine through the intermediate receive output, Pin REOUT (Pin 20). * 4) Incoming message playback ; The line is open, TEA7092 is powered from the +5V and the incoming message is sent from the answering machine to TEA7092 through the Pin LSIN (Pin 5) and amplified in TEA7092 loudspeaker amplifier to be heard in the loudspeaker. Wh en T EA7 092 is powered wit h +5V on Pin VLS (Pin 1), the maximum power on the loudspeaker is : - On RLS = 25 : 100mW - On RLS = 32 : 80mW - On RLS = 50 : 50mW
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
III - CALL PROGRESS MONITOR AND GROUP LISTENING MODES (continued) III.7 - Ring Melody Control Mode Note : For complementary information, see Section IV.3 - Serial bus interface. In OFF-HOOK mode it is possible to control the ring melody using the loudspeaker. Figure 55 : Flow Chart
ON-HOOK
The ring melody is audible only in the loudspeaker. This feature is enabled by the serial code : 0 1 1 0 0 1 1.
OFF-HOOK
HANDSFREE MODE 0110010
or
OFF-HOOK HANDSET MODE
HANDSFREE MODE - AGC ON or OFF - Sidetone configuration - Squelch ON or OFF - Decay PON current value - Antiacoustic feed back value - Speech - Dialing sequence - Mutes - Error beep - Sine wave sequence
CONFIGURATION CODES SETTING
OPERATING CODES
RING MELODY CONTROL 0 11 0 01 1
Fi1 Code + Divider 1 Code 0 00 XX X X + 1 XX X X X X The Ring melody is made of N frequencies, the duration of each frequency is determined by the microcontroller
Fi2 Code + Divider 2 Code 0 00 XX X X + 1 XX X X X X
FiN Code + Divider N Code 0 00 XX X X + 1 XX X X X X
HANDSFREE MODE 0110010
or
HANDSET MODE 0 11 0 00 0
37/57
AN848-56.EPS
HANDSFREE MODE with the last OPERATING code used before Ring melody control and Configuration codes still stored
HANDSET MODE with the last OPERATING code used before Ring melody control and Configuration codes still stored
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
III - CALL PROGRESS MONITOR AND GROUP LISTENING MODES (continued) III.8 - Beep Error Generator Note : For complementary information, see Section IV.3 - Serial bus interface. In OFF-HOOK mode it is possible to send a square wave signal in the earphone and in the loudspeaker by using the ring frequency generator, all frequencies available in ring mode are available in Beep error mode. Figure 56 : Flow Chart
ON-HOOK ON-HOOK
This feature is enabled by the serial code : 0 0 1 1 1 0 0 , which sent the square wave in the earphone. To send the beep error on the loudspeaker it is necessary to complete the previous sequence with the Group listening code : 0 1 1 0 0 0 1.
OFF-HOOK HANDSET MODE
OFF-HOOK HANDSET MODE
Fi Code + Divider Code 0 00 X XXX + 1 XX X XX X
VOLUME CONTROL 010 0XXX
ERROR BEEP 00 11 100
GROUP LISTENING CODE 0 11 0001
BEEP SENT IN THE EARPHONE
GROUP LISTENING MODE
SPEECH CODE 00 10 000
Fi Code + Divider Code 0 00XXXX + 1XXXXXX
NEW BEEP No HANDSET MODE
Yes
ERROR BEEP 0 01 1100
BEEP SENT IN THE EARPHONE AND IN THE LOUDSPEAKER
SPEECH CODE 0 01 0000
NEW BEEP No
Yes
AN848-57.EPS
GROUP LISTENING MODE
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TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
IV - MICROCONTROLLER INTERFACE IV.1 - Microcontroller Power Supply The microcontroller is used in every modes, speech, dialing and ring. It is requested to start quickly in ring mode, less than 200ms and to maintain the supply on the microcontroller in pulse dialing mode, with a low voltage across the telephoneset, or during an earth loop connection, in these two modes the microcontroller is supplied through the energy previously stocked in a capacitor and this capacitor should be able to maintain the power on the microcontroller during one second. This compromise between the different modes is carried out through the microcontroller power management which is connectedon Pin VMC (Pin 2) and on Pin VRMC (Pin 8). Figure 57 shows the microcontroller power supply management. In OFF-HOOK mode : - C10 on Pin VMC (Pin 2) is charged in priority with the Istartup (ILS) currentsource and is, after Reset high, powered with IVMC (see Section II.1.3 START UP CHARACTERISTICS). - The voltage on Pin VMC (Pin 2) is equal to : VL (Pin 3) - 0.4V - In Pulse dialing mode the microcontroller connected on the 3.5V regulated voltage, Pin VRMC (Pin 8), is powered through the serial regulator. In Ring mode : - For the microcontroller power supply only the Figure 57
VL
3
c a p ac it or C1 5 of 4 . 7F co n n e c te d o n Pin VRMC (Pin 8) has to be charged, so the startup time in ring mode can be less than 200ms. IV.2 - Reset and Pon Signals These two pieces of information give the status of the Pin VRMC (Pin 8) and of the line current, IL. In OFF-HOOK mode : - Pin RESET (Pin 11) goes at high level when VRMC reaches 2.6V and then remains at high level until VRMC reaches the decay threshold fixed at 2.5V, or the Reset code (0 0 1 0 1 1 1) is received through the serial bus interface when PON is at low level. If the Reset code has been previously sent Pin RESET (Pin 11) goes back to an high level, if VRMC is higher than the rise threshold, on a rise edge of PON signal. Note : when PON is at high level, the Reset code is inhibited. - Pin PON (Pin 12) goes at high level when the voltage at Pin VRMC (Pin 8) reaches 2.6V and the line current (IL) reaches the value of 12mA, and then remains at high level until the line current (IL) goes below the threshold level fixed through the configuration code sent on the serial bus interface. * Decay threshold level : IL = 12mA by default configuration. * Decay threshold level : IL = 4mA if the code (0 1 1 1 0 0 1) is sent.
TEA7092
IVMC Close if RESET Low and IL Present
2
ISTART = ILS
1 VLS
VMC Battery + C10 470F
VRMC
8
3.5V + C15 4.7F F + LCD
Info for PON & RESET 470k
VBANDGAP
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AN848-58.EPS
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
IV - MICROCONTROLLER INTERFACE (continued) IV.2 - Reset And Pon Signals (continued) Figure 58 shows the RESET and PON signals in different modes. Different modes : - A: ON-HOOK mode RESETand PONstayat lowlevel - B : START UP, as soon as the voltage on VRMC reaches the rising threshold and the line current, IL is higher than 12mA, RESET and PON go at high level. - C : PULSE DIALING, PON follows the line current, IL and RESET stays at high level. - D : SPEECH or DTMF, RESET and PON stay at high level - E : LINE BREAK EXCHANGE duration less than td, as soon as the line current, IL, goes lower than the programmed threshold level (12 or 4mA), the PON signal goes to low level, the microcontroller detects it and starts an internal counter, if the feeding break is less than a prefixed td value (200ms for example), PON goes back to high level with the line current, IL and the feedingbreak Figure 58
IL VMC 5.6V 2.7V t VRMC 3.5V 2.6V t PON tD tD t RESET t A : ON-HOOK B : START-UP + SPEECH C : PULSE DIALING D : SPEECH or DTMF E : LINE BREAK EXCHANGE DURATION F : LINE BREAK EXCHANG DURATION > td Td : Delay Fixed by the Microcontroller Reset code (0010111) sent by the microcontroller
AN848-59.EPS
is ignored by the kit TEA7092and microcontroller. - F : LINE BREAK EXCHANGE duration more than td, as soon as the line current, IL, goes lower than the programmed threshold level (12 or 4mA), the PON signal goes to low level, the microcontroller detects it and starts an internal counter, if the feeding break is more than a prefixed td value (200ms for example), when the counter reaches 200ms is sent the Reset code (0 0 1 0 1 1 1) to the TEA7092 and the pin RESET (Pin 11) goes to low level, on this signal the microcontroller goes in reset condition. In RING mode : - Pin RESET (Pin 11) goes at high level when the voltage at Pin VRMC (Pin 8) reaches the rise threshold and then remains at high level until Pin VRMC (Pin 8) reaches, when the ring input voltage disappears, the decay threshold. - Pin PON (Pin 12) stays at low level.
A
B
C
D
E
D
F
D
A t 2.6V
2.5V
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TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
IV - MICROCONTROLLER INTERFACE (continued) IV.3 - Serial Bus Interface Figure 59
t1 CLK Pin 13 DATA Pin 14 Synchro Datas should Change During Clk = 1 A Standard 8-bit Code can be Sent, the Last One is Ignored a0 a1 a2 a3 a4 a5 a6
AN848-60.EPS
t2
t1
t1
t1
t1 > 1s ; t2 > 2s
IV.3.1 - Different Codes The serial bus interface works with 7 significant bits, a standard 8 bit code can be used, TEA7092 only takes care of the seven first bits. Figure 59 shows the timing of the Pin CLK (Pin 19) and of the Pin DATA (Pin 20).
- The OPERATING codes which are related to the MODE codes : Each operating code can be used under each mode code. When an operating code is sent, the previous one is cancelled.
Codes a6 a5 a4 a3 a2 a1 a0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 0 0 0 0 1 1 1 0 0 0 0 1 1 1 0 0 1 1 0 0 1 0 1 0 1 0 1 0 Speech Dialing Mute in Transmit and Receive Paths Mute in Transmit Path Error Beep Sine wave High Frequency Group Sine wave Low Frequency Group Remarks
TEA7092 Initialization After Pin RESET (Pin 11) goes high, TEA7092 is initialized, the internal default programmed codes are given in Bold in the following code tables. Codes programming TEA7092 are : - The MODE codes : The mode codes are the upper level of codes.
Codes a6 a5 a4 a3 a2 01100 01100 01100 a1 0 0 1 Remarks a0 0 Handset Mode 1 Group Listening Mode 0 Handsfree Mode
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TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
IV - MICROCONTROLLER INTERFACE (continued) IV.3.1 - Different Codes (continued) - The FLIP-FLOP codes, each time they are sent, TEA7092 returns to the previous configuration. Each Flip-Flop code is an independent one, its configuration is not modified by any other code, excepted the "Initialization" code and the "Reset" code. These codes are accessible through the telephone set user, for example : The +6dB mode on the earphone which increases the earphone level is accessible through a dedicated key of the telephone set keyboard.
Codes a6 a5 a4 a3 a2 a1 a0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 0 0 1 0 1 1 1 0 1 0 0 1 1 1 1 1 0 0 0 0 VL(3) DC Speech / VL(3) DC Pulse Dialing Normal Receive Gain / +6dB Receive Gain No Transfer / Transfer Request Normal Transmit Gain / -6dB Transmit Gain Oscillator ON / Oscillator in Stand by Mode Remarks Codes Remarks a6 a5 a4 a3 a2 a1 a0 0 0 1 0 1 0 0 AGC on Tx & Rx Paths / No AGC on Tx & Rx Paths 0 0 1 1 0 0 0 Line Tracking Sidetone Network / Single Sidetone Network = 3/4 x ZALL + 1/4 x ZASL 0 0 1 1 0 1 1 Line Tracking Sidetone Network /Single Sidetone Network = ZASL 0 0 1 1 0 0 1 Squelch Feature ON / Squelch Feature Inhibited 0 1 1 1 0 0 0 Dec ay P O N C u r ren t Threshold = 12mA 0 1 1 1 0 0 1 Dec a y PO N C urr en t Threshold = 4mA 0 1 1 1 1 0 0 Antiacoustic F eedback Stage Attenuator = 10dB 0 1 1 1 1 0 1 Antiacoustic Feedback Stage Attenuator = 15dB 0 1 1 1 1 1 0 Antiacoustic F eedback Stage Attenuator = 20dB 0 1 1 1 1 1 1 Antiacoustic F eedback Stage Attenuator = 25dB
- The CONFIGURATION codes, which are generally sent once to program a telephone set at each OFF-HOOK action, such as PABX connection or PON threshold level for example. are not accessible through the telephone set user. Excepted the Antiacoustic feedback stage attenuator value and the Decay PON current threshold, each code is an independant one, its configuration is not modified by any other code, except for the "Initialization" code and the "Reset" code. Except for the Antiacoustic feedback stage attenuator programmation codes and the Decay PON current threshold,all the other Configuration codes are Flip-Flop codes.
- The LOUDSPEAKER VOLUME CONTROL codes. These codes are memorized, independtly from the mode or operating code. For example one of these codes can be sent in Handset mode and when the Group listening mode code is sent, the loudspeaker output volume will be the one programmed in the Handset mode.
Codes Remarks a6 a5 a4 a3 a2 a1 a0 0 1 0 0 1 1 1 Gmax 0 1 0 0 1 1 0 Gmax - 4dB 0 1 0 0 1 0 1 Gmax - 8dB 0 1 0 0 1 0 0 Gmax - 12dB 0 1 0 0 0 1 1 Gmax - 16dB 0 1 0 0 0 1 0 Gmax - 20dB 0 1 0 0 0 0 1 Gmax - 24dB 0 1 0 0 0 0 0 Gmax - 28dB 0 1 1 1 0 1 1 -21dB Attenuation Adder In Ring Mode*
* Flip-Flop code.
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TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
IV - MICROCONTROLLER INTERFACE (continued) IV.3.1 - Different Codes (continued) - HFIN input selection For answering machine or cordless connection, it can be requested to select HFIN (Pin 22) input, without enabling the loudspeaker, for this the following procedure should be sent : * Handsfree code : 0 1 1 0 0 1 0 * Tx & Rx mutes : 0 0 1 0 0 1 0 * HFIN input select : 0 1 1 0 1 1 1 To go back to handsfree mode, send : * Speech mode : 0 0 1 0 0 0 0 Or to go back to handset mode, send : * Speech mode : 0 0 1 0 0 0 0 * Handset code : 0 1 1 0 0 0 0 - The DTMF and SINE WAVE codes. These codes are memorized, independtly from the mode or operating code. For example one of these code can be sent in Handset mode and when the Dialing mode code is sent, the DTMF frequencies sent on the line are those previously programmed in the Handset mode.
Codes a6 a5 a4 a3 a2 a1 a0 0000000 0000001 0000010 0000011 0000100 0000101 0000110 0000111 0001000 0001001 0001010 0001011 0001100 0001101 0001110 0001111 Key in DTMF Dialing "2" "1" "A" "3" "8" "7" "C" "9" "5" "4" "B" "6" "0" "*" "D" "#" DTMF Dialing (Code 0010001 sent before) 697Hz 697Hz 697Hz 697Hz 852Hz 852Hz 852Hz 852Hz 770Hz 770Hz 770Hz 770Hz 941Hz 941Hz 941Hz 941Hz + 1336Hz + 1209Hz + 1633Hz + 1477Hz + 1336Hz + 1209Hz + 1633Hz + 1477Hz + 1336Hz + 1209Hz + 1633Hz + 1477Hz + 1336Hz + 1209Hz + 1633Hz + 1477Hz SINE WAVE (Code 0011101 or 0011110 sent before) 348Hz or 604Hz
426Hz or 738Hz 385Hz or 668Hz
470Hz or 816Hz
- The Other Codes
Codes Remarks a6 a5 a4 a3 a2 a1 a0 0 0 1 0 0 0 1 Ring Start 0 0 1 0 1 1 1 Reset Control (High to Low level on Pin 11 (RESET)), Internal TEA7092 Initialization and Microprocessor Serial Bus Connection Inhibited 0 1 1 0 0 1 1 Ring Melody Control, to listen the Ring Melody in the Loudspeaker During OFF-HOOK Mode. 0 1 0 1 0 0 0 TEA7092 Initialization (to go back to internal default programmation)
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TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
IV - MICROCONTROLLER INTERFACE (continued) IV.3.1 - Different Codes (continued) - The RING and ERROR BEEP FREQUENCY codes
Ring Frequencies (Hz) (see Note) Divider Codes 1010000 1010001 1010010 1010011 1010100 1010101 1010110 1010111 1011000 1011001 1011010 1011011 1011100 1011101 1011110 1011111 1100000 1100001 1100010 1100011 1100100 1100101 1100110 1100111 1101000 1101001 1101010 1101011 1101100 1101101 1101110 1101111 1110000 1110001 1110010 1110011 1110100 1110101 1110110 1110111 1111000 1111001 1111010 1111011 1111100 1111101 1111110 1111111 n 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 1645.0 1548.3 1462.3 1385.3 1316.0 1253.4 1196.4 1144.4 1096.7 1052.8 1012.3 974.8 940.0 907.6 877.4 849.1 822.5 797.6 774.1 752.0 731.1 711.4 692.7 674.9 658.0 642.0 626.7 612.1 598.2 584.9 572.2 560.0 548.3 537.2 526.4 516.1 506.2 496.6 487.4 478.6 470.0 461.8 453.8 446.1 438.7 431.5 424.5 417.8 Fi Codes (Hz) 26321 (000XX10) 23551 (000XX11) 21308 (000XX00) 19455 (000XX01) 1471.9 1385.3 1308.4 1239.5 1177.5 1121.5 1070.5 1024.0 981.3 942.0 905.8 872.3 841.1 812.1 785.0 759.7 736.0 713.7 692.7 672.9 654.2 636.5 619.8 603.9 588.8 574.4 560.7 547.7 535.2 523.4 512.0 501.1 490.6 480.6 471.0 461.8 452.9 444.4 436.1 428.2 420.5 413.2 406.0 399.2 392.5 386.1 379.8 373.8 1331.7 1253.4 1183.8 1121.5 1065.4 1014.7 968.5 926.4 887.8 852.3 819.5 789.2 761.0 734.8 710.3 687.3 665.9 645.7 626.7 608.8 591.9 575.9 560.7 546.4 532.7 519.7 507.3 495.5 484.3 473.5 463.2 453.4 443.9 434.9 426.2 417.8 409.8 402.0 394.6 387.4 380.5 373.8 367.4 361.1 355.1 349.3 343.7 338.2 1215.9 1144.4 1080.8 1023.9 972.7 926.4 884.3 845.9 810.6 778.2 748.3 720.6 694.8 670.9 648.5 627.6 608.0 589.5 572.2 555.9 540.4 525.8 512.0 498.8 486.4 474.5 463.2 452.4 442.2 432.3 422.9 413.9 405.3 397.0 389.1 381.5 374.1 367.1 360.3 353.7 347.4 341.3 335.4 329.7 324.2 318.9 313.8 308.8
These codes are memorized, independtly from the mode or operating code. For example one of these code can be sent in Handset mode and when the Error Beep code is sent, the square wave frequency sent on the earphone is the one previously programmed in the Handset mode.
Note : It is possible to program n from 1 to 15, 1.0.0.0.0.0.0 to 1.0.0.1.1.1.1, the frequency values are not given in the previous table, but can be calculated in the same way.
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TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
IV - MICROCONTROLLER INTERFACE (continued) IV.3.2 - Software Example Sequence : ON-HOOK ; OFF-HOOK ; AGC OFF ; HANDSET ; DTMF dialing ; GROUP LISTENING ; ERROR BEEP ; +6dB on earphone ; Normal gain on earphone; ON-HOOK. Figure 60 : Flow Chart
ON-HOOK TEA7092 Initializated in Default Mode PON = 1 & RESET = 1 Configuration Code AGC Inhibited in Tx & Rx Paths
VOLUME CONTROL 0 1 00 XX X
Loudspeaker Output Level Adjustment
OFF-HOOK HANDSET MODE
UP/DOWN No
Yes
AGC OFF 00 101 00
Fi Code + Divider Code 000XXXX + 1XXXXXX
No NUMERIC KEY PRESSED Yes KEY CODE 0 00 XX XX
ERROR BEEP 0 0111 00 OPERATING CODE Error Beep Mode
BEEP SENT IN THE EARPHONE AND IN THE LOUDSPEAKER
DTMF Dialing
DIALING CODE 00 100 01
SPEECH CODE 0 0100 00
DTMF SENT NEW BEEP MUTE MIC & EAR 00 100 10 No GROUP LISTENING MODE INTER DIGIT PAUSE HANDSET CODE 0 1100 00 SPEECH CODE 00 100 00 HANDSET MODE Group Listening Requested GROUP LISTENING CODE 01 100 01 Handset Mode Requested Yes
+6dB ON EARPHONE 0 0101 10 FILP-FLOP CODE Earphone Level Change NORMAL GAIN ON EARPHONE 0 0101 10
AN848-61.EPS
GROUP LISTENING MODE
ON-HOOK
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TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
IV - MICROCONTROLLER INTERFACE (continued) IV.3.3 - Serial Bus Code Actions on Switches Figure 61, Tables below give the switch positions and the generator status for the different serial codes sent on the serial bus interface. Figure 61
HANDSET Microphone HANDSFREE Microphone SW1
1 2
0dB or -6dB
SW2
1
Output Amp To Line
2
DTMF GENERATOR SINEWAVE GENERATOR
TRANSMIT CHANNEL
From Line
0dB or -6dB
SW3
1
Earphone
2
SW4
1
SW5
1
DTMF GENERATOR SINEWAVE GENERATOR ERROR BEEP GENERATOR
RING GENERATOR
2 2
Loudspeaker RING MELODY CONTROL GENERATOR
RECEIVE CHANNEL
The mode codes, Handset, Group listening act only on switches SW1 and SW5.
Switches Codes Default Handset Mode Group Listening Mode Handsfree Mode Ring melody control SW1 SW2 SW3 SW4 SW5 0110000 0110001 0110010 0110011 1 1 1 2 1 1 1 2 2 2 1 1 2 2 1 1 2 DTMF Generators Error Sinewave beep Ring Melody Control Disabled Disabled Disabled Disabled Enabled
Disabled
The Operating codes act only on switches SW2, SW3 and SW4, the positions on the switches SW1 and SW5 are the ones previously determined by the Mode codes. Note : In Ring Melody Control, the operating codes are not accessible.
Operating Codes Speech Dialing Mute in Tx & Rx Mute in Tx Error Beep Sinewave HF Group Sinewave LF Group 0010000 0010001 0010010 0010011 0011100 0011101 0011110 SW2 1 2 2 2 1 2 2 Switches SW3 SW4 1/2* 1 2 2 2 2 1/2* 1 2 2 2 2 2 2 DTMF Disabled Enabled Disabled Disabled Disabled Disabled Disabled Generators Sinewave Disabled Disabled Disabled Disabled Disabled Enabled Enabled Error Beep Disabled Disabled Disabled Disabled Enabled Disabled Disabled
* 1 for Handset and Group listening modes, 2 for Handsfree mode.
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AN848-62.EPS
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
IV - MICROCONTROLLER INTERFACE (continued) IV.4 - Ring Indicator - Line Current Variation Indicator The Pin RI/VI (Pin 10) is used for different modes : - In Ring mode, when the threshold level, programmed on Pin RSU (Pin 40), is reached and t h e Pin RE SE T (P in 11 ) is h igh , t h e Pin RI/VI (Pin 10) goes to high logic level. - In OFF-HOOK mode the pin RI/VI (Pin 10) gives an indication of the line current variation when the transfer feature is requested. The transfer feature happens when there are two telephone sets connected in parallel on the same line and the user wants to transfer the communication from telephone "1" to telephone "2" and ONHOOK telephone "1". With TEA7092 in telephone "1". Telephone "1" is in speech mode, the user presses the "Transfer" key on telephone "1". When the "Transfer" key is pressed, the microcontroller sends the Transfert code (0 0 1 1 0 1 0) and TEA7092 memorizes the line current value. The user ON-HOOK telephone "1", the line is maintained closed by the microcontroller, through the pulse dialing high voltage stage. When the user OFF-HOOK telephone "2", the line current value in telephone"1" decreases, TEA7092 detects this line current variation and the Pin RI/VI goes to high logic level. When the microcontroller receives this signal it puts off the high voltage stage of telephone "1". Telephone "1" goes in OFF-HOOK mode. Figure 62 gives the value of the line current variation (IL) which generates a high logic level on Pin RI/VI (Pin 10). IV.5 - Oscillator The Oscillator is powered on Pin VRMC (Pin 8). The oscillator is only used for DTMF, sine wave, beep error, ring frequency generator and transfer feature. In Pulse dialing flash or earth button, it is preferable t o r ed u c e , t h e cu rren t co n su mp tion o n Pin VRMC (Pin 8) as low as possible, in order to have the lowest possible value of capacitor on Pin VMC (Pin 2). The toggle code (0 1 1 1 0 1 0) puts the Oscillator in stand by mode or not. The current consumption on Pin VRMC (Pin 8) is : - Oscillator ON : 250A - Oscillator OFF : 50A The default condition is Oscillator ON. If the microcontroller has a 3.58MHz resonator, the oscillator output of the microcontroller can be connected, through a capacitor, to the Pin OSC (Pin 9) so as to provide TEA7092 with the 3.58MHz signal. IV.6 - Microcontroller Signal Control in the Different Modes The following table lists the configuration of the signals given by TEA7092 in the different modes :
Signals/Modes ON-HOOK OFF-HOO K RING Line Current Variation Detected in Transfer Mode External Supply Only Reset 0 1 1 1 1 PON 0 1 0 1 0 RI/IVI 0 0 1 1 0
Figure 62 : Current Line Variation to Detect Transfer
16 14 12
IL (mA)
10 8 6 4 2
AN848-63.EPS
0 10 20 30 40 50 60 70 80 90 100 110 120 IL (mA)
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TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
V - DIALER FEATURES V.1 - DTMF Dialer Figure 63
EAR+
35
EAR36
VL
3
ZB
DTMF/SINEWAVE
40k
DTMF1 C13 DTMF2 C32
7
-1 10k I L/85 from DC path
42
10k 9k Mute 45k
LOUDSPEAKER CURRENT SOURCE Mirror 1/40
1
V LS 0dB 1k From Microphone 5k
+ C1
TEA7092
25 21
AN848-64.EPS
VREF R8 C14
GTR
The DTMF dialer generates the frequencies in order to drive a telephone set keyboard and complies with the recommandation Q.23 of the CCITT-T/CS 46-02. It generates : - The low frequency group (697, 770, 852, 941Hz) - The high frequency group (1209, 1336, 1477, 1633Hz) Figure 63 shows the DTMF amplifier path. The MUTE signal driven through the serial bus, selects the microphone signal or the DTMF signal and the confidence tone level for the earphone and the loudspeaker. T h e DT MF lev e l is f ix ed by C13 on Pin DTMF1 (Pin 7) and by R8 on Pin GTR (Pin 21), C32 on Pin DTMF2 (Pin 42) fixes the cut off frequency of the second filter. - Cut-off frequency on DTMF1 :
f1 = 1
Figure 64
SPEECH MODE
No NUMERIC KEY PRESSED Yes KEY CODE 000XXXX
DIALING CODE 0010001
DTMF MODE
MUTE 0010010
2 20 103 C13
with C13 = 47nF, f1 = 170Hz.
INTERDIGIT PAUSE
An internal twist between each DTMF frequency is programmed so as to take care to follow the T/CS46-02 recommended levels. - Cut-off frequency on DTMF2 :
f2 = 1
Yes
NUMERIC KEY PRESSED No SPEECH CODE 0010000
AN848-65.EPS
2 10 103 C32
with C32 = 2.7nF, f2 = 5.9kHz.
Figure 64 shows the DTMF signaling.
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TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
V - DIALER FEATURES (continued) V.2 - Sinewave Generator The Sinewave generator is programmable like the DTMF generator. This one generates the DTMF frequencies divided by 2, in single tone mode in two groups : - CodeDTMF + code 0011101: 348,385,426, 470Hz - CodeDTMF + code 0011110: 604,668, 738, 816Hz The sinewave level on line is 8dB lower than the DTMF dialing level. This sinewave generator can be used in mute mode to send on line a signal to advise the other party than you are in Secret mode. V.3 - Pulse Dialer Interface In pulse dialing mode, if the code (0 0 1 0 1 0 1) is Figure 65 : Mask / No Mask Mode
Pulse DialingMode Other Modes Flash Other Modes
used, the voltage across TEA7092 is reduced to 2V on Pin VL (Pin 3), this way it is possible to achieve a low voltage across the telephone set during the make period of the pulse dialing sequence. Figure 65 shows the DC voltage across TEA7092 and across the telephone set in pulse dialing mode. Note : It is possible to generatean acoustic control in the earphone in pulse dialing mode with the code (0010101). This code should be sent twice within the break period of the pulse dialing. For example, if the break period is 60ms, send the code (0010101) 10ms after the start of the break period and send it again 10ms before the end of the break period. This will generate a DC level change in the earphone which will be audible.
DP (P Output) Code (0 0 1 0 1 0 1) Sent VL (V) 2 0 VSET (V) 5V max. 0 t
AN848-66.EPS
t
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TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
VI - RINGER FEATURES VI.1 - Ringer Power Supply In ring mode only the ring part, the loudspeaker amplifier, the logic part and the microcontroller supply are powered. The supply is provided by a switch mode power supply. Figure 66 shows the ring part. The switch mode power supply converts the high ac ring line voltage, 30 to 90VRMS at 25 or 50Hz, into a low DC voltage, 3 to 5.6V, which is used to supply the loudspeaker amplifier and the microcontroller. The switch mode power supply made by T1, T2, L1, D7 and the resistors associated, is driven through the Pin SWP (Pin 39). The control on SWP is done by a 26kHz oscillator. The coil L1 is 1mH, the diode D7 is a 1N4148. Figure 66
VRING + I(VZP) R37 R35 C6 D2 R36 R32 C30 R38 D3 T2 R33 D7 C1 L1 T1 +
VI.2 - Start-Up Threshold Level By default, the ring threshold level is internally set up at 18.8VDC on Pin RSU (Pin 40) : (3 x 5.6V + VBE (0.6V) + 2 x VTHN (2 x 0.7V)), equivalent to an AC ring level of 13.3VRMS. As soon as this threshold level is reached, is a 11.2V hysteresis is introduced to assurethe system's stability T h e VRING1 s t art u p le v el is s e t u p o n Pin RSU (Pin 40) with R35 and if neccessary a zener diode D5 added in serial with R35, most of the countries don't request D5. VRING1 : Start up level. R35 0.7 + VZ(D5) in V VRING1 = 18.8 + 300k Note : Recommended value for R35 is 56k.
VZP
RSU
38 40
SWP 24V IVZP Info
39 1
VLS
8
VRMC +
11.2V 2.6V 5.6V 135k 26kHz LOGIC CONTROL SERIAL REGULATOR 100A
C15
1.2V 150k VLS > 2.6V 150k VRMC LOGIC CONTROL > 2.6V Fi Ring IA = f{(IVZP)} VIN LS AMP (VLS - VLSOUT) < 0.2V
44
LSSOF 90k RI I/17.5k 40k
6
C19
R31
RI
LSOUT + C2
TEA7092
RCO
Gain = 16
41
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AN848-67.EPS
C4
R40
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
VI - RINGER FEATURES (continued) VI.3 - Ring Frequency Generator The ring frequency values which can be generated are those given Page 45 of this application note. On the Table given at Page 45, only the frequency values for n > 15 are given, the frequency values from n = 1 (1000000)to n = 15 (1001111) are also accessible, if it is neccessary to generate a frequency higher than 1645Hz. VI.4 - Output Power Optimization The power available on Pin LSOUT (Pin 44) depends on : - The country requires : * Minimum input ac level in test conditions. * Ring impedance. Taking in account these main requests the power on Pin LSOUT (Pin 44) is optimized through the resistor R40 connected on Pin RCO (Pin 41). - The yield of the switch mode power supply. The principal parameters which influence the yield are : * D7 VBE value. * T1 VCEsat and base current values (the maximum IC PEAK value is 100mA). * L1 serial resistor value. * Current consumption on Pin VZP (Pin 38) and on Pin RSU (Pin 40). * Bias current consumption on Pin VLS This paragraph gives information on : - The switch mode power supply concept. - The switch mode power supply yield. - The ring output power optimization on Pin LSOUT (Pin 44). Figure 67
SW1 IEt IE L1 RL1 IS ISRL
VI.4.1 - Switch Mode Power Supply Concept After the ring bridge, the switch mode power supply concept is represented in Figure 67. Input voltage equivalent to VRING1 VE VE1 Input voltage after the switch SW1 IE Mean input current VS Output voltage at Pin VLS (Pin 1) Mean output current IS Voltage across D7 when it is in VD forward mode IE0 Primary bias current IS0 Secondarybias current RL1 Resistive part of the coil L1 Switch SW1 - VCEsat of T1 PNP - IB1, T1 base current - tD, T1 desaturation time - VE1 = VE - VCEsat(T1) Figure 68 gives the voltage,VE1, the current in the coil, ISELF, the current in D7, IDIODE and the current in the switch SW1 given by C6, ICAPA. The value of the maximum current in the coil is fixed by tON and tOFF depends on RL. When RL decreases, t ON increases. The coil value should be calculated so that the current in the coil reaches the zero value with the minimum charge. VE1 - VLS (1) IMax. = tON L L is the value of the coil L1. The ratio between tON and tOFF is : tON VD + VLS = (2) tOFF VE1 - VLS The output current IS is : IMax. tON + tOFF (3) IS = 2 t
VE
C5
IE0 VE1
D7
C1
IS0
VLS
RL
AN848-68.EPS
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TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
VI - RINGER FEATURES (continued) VI.4 - Output Power Optimization (continued) Figure 68
VE1 tON tOFF
VS -VD ICOIL t = 38.46s t is internally fixed by the 26kHz Oscillator t ICAPA t
t IDIODE t
AN848-69EPS
VI.4.2 - Switch Mode Power Supply Losses The sum of all the different losses gives the yield of the switch mode power supply. The final yield is : POUT final = POUT + Pi where : Pi are the different losses, POUT is the power in the load RL : POUT = 4 x RL x (ISRL)2. The output current IS is : IS = ISRL + IS0.
Using the equations (1), (2) and (3), the values of tON and tOFF can be found :
tON = t
2 L f I (V - V ) (V + V )
VLS + VD
LS S E1 E1 D
f = 26kHz
tOFF = t
2 L f I (V + V ) (V + V )
VE1 - VLS
D S LS E1 D
IMax. =
LfI V +V
2
S E1 D
(VE1 - VLS) (VLS + VD)
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TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
VI - RINGER FEATURES (continued) VI.4 - Output Power Optimization (continued) The different losses are : - In the switch SW1 : IMax. tON VCEsat * VCEsat : PVCEsat = 2t VLS + VD = IS VCEsat VE1 + VD * T1 base current (IBT1) : tON PIBT1 = VE IBT1 - The sum of the losses is : PTOTAL = Pi = PVCEsat + PIBT1 + Pdesat + PIBT2 + PVZP + PRSU + Pcoil + PVLS + PP + POLS + Pdiode VI.4.3 - Output Power Adjustment The optimization of the ouput power depends on the system environment. It is therefore neccessary to know the power which can be given by the system in the best and worst loop line. Each country has a different loop line system. Figure 69 shows the system configuration. Figure 69
TELEPHONE SET RL Ring RC Network Fixed by the Country requirement PE
t
= VE IBT1
* tD, desaturationtime of T1 : IMax. tD Pdesat = VE 25 t = VE tD
V (V - V (V + )
E1 LS)
2 L f (VLS + VD)
E1
D

2 f IS (VE1 - VLS) (VLS + VD) L (VE1 + VD)
* T2 base current (IBT2) : PIBT2 =
(VE - 8.2)2 R32
VRGENE (20 to 60Hz)
- In the diode D7 : IMax. tOFF VD PDIODE = 2t VE1 - VS = IS VD VE1 + VD - At the primary ; The sum of these losses is equal to : VE x IE0 * On Pin VZP (Pin 38) : VZP (Pin 38) = 2.55V ; (VE - 2.55)2 PVZP = R34 + R37 * On Pin RSU (Pin 40) : (VE - 5.6) VE PRSU = R35 + 300k - In the coil : Pcoil = Rcoil
VE
The minimum power available, PE1 is for : VRGENE(Min.) and RL(Max). The maximum power available, PE2 is for : VRGENE(Max.) and RL(Min). Figure 70 gives the power available at the input of the switch mode power supply. Figure 70
PE (mW) PE2 VRGENE (Max.) RL (Min.)
IMax.
2
2
tON2 + tOFF2 t
2 2 2
(VE1 + VD) 2 - At the secondary ; The sum of these losses is equal to : VLS x IS0 * Current consumption of all the part powered on Pin VLS (Pin 1) : PVLS = VLS x IPLS. * Current consumption of the microcontroller : PP = VLS x IP ; IS0 = IPLS + IP. * VCEsat of the loudspeakeramplifier output stage : POLS = 0.2 x ISRL
= Rcoil IS2
(VE1 - VLS) + (VLS + VD)
VRGENE (Min.) RL (Max.) PE1
AN848-71.EPS
VE1
VE2
VE (V)
The output signal on Pin LSOUT (Pin 44) is controlled through the current information given on Pin VZP (Pin 38) (see Figure 66).
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AN848-70.EPS
C
R
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
VI - RINGER FEATURES (continued) VI.4 - Output Power Optimization (continued) The principle is : - From the current I(VZP) in the resistor R37, a current IA is issued and equal to : 2.6 I(VZP) - 39A - R38 (1) IA = 9 The 39A current is the bias current of the internal 2.6V zener connected on Pin VZP (Pin 38). I(VZP) = VRING - 2.6 The Figure 71 gives the voltage on Pin VLS (Pin 1), on Pin RCO (Pin 41) and the VPP(LSOUT) on Pin LSOUT (Pin 44) versus the VRING input voltage with : R37 = 200k, R38 = 150k, R40 = 47k The values of R37, R38 and R40 should be calculate to adapt the output power requested on Pin LSOUT (Pin 44) to the available power, during ring mode, on the terminal wire as described on Figures 69 and 70 of this application note. The recommended values for a ring network of, CRING = 1F, RRING = 1.5k are : - R37 = 200k, R38 = 150k - P40 = 47k, if fRING = 25 or 50Hz / RLOUDSPEAKER = 50 - R40 = 39k, if fRING = 50Hz / RLOUDSPEAKER = 32 - R40 = 33k, if fRING = 25Hz / RLOUDSPEAKER = 32 VI.5 - Microcontroller Management (RI / RESET) In ring mode, two pieces of information are given to control the microcontroller : - Pin RESET (Pin 11) which goes at level "1" if Pin VRMC (Pin 8) > 2.6V. - Pin RI/VI (Pin 10) which goes at level "1" if : * Pin RSU (Pin 40) > 19V * Pin VRMC (Pin 8) > 2.6V * Current in Pin VZP (Pin 38) > 40A - After a ring mode, Pin RI/VI (Pin 10) goes back to level "0", if Pin RSU (Pin 40) goes lower than 8V. Figure 71
8 7 6 U (V) 5 4 3 NO 2 WORKING AREA 1 0 0 10 20 30 VRING (V) 40 50
AN848-72.EPS
R37
(2)
- T h e c u rre nt I A g en erat es a vo lt a ge on Pin RCO (Pin 41) equal to : V(RCO) = R40 x IA (3) - This input voltage, mixed with the ring frequency is amplified to the loudspeaker connected on pin LSOUT (Pin 44), and the peak to peak square output voltage VPP(LSOUT) is : VPP(LSOUT) = 16 x V(RCO) (4) (1), (2), (3) & (4)
VPP(LSOUT) = VRING 16 2.6 R40 - 39A - 9 R35//R38 R37
When the VRING input voltage is high enough to s a t u ra t e t h e o ut p u t st a ge on Pin LSOUT (Pin 44), compared to Pin VLS (Pin 1), (VLS (Pin 1) - VPP (LSOUT) < 0.2V), the switch in serial with the current source on Pin LSSOF (Pin 6) is a c t iva te d , a nd t h e in pu t v olt a ge o n Pin LSSOF (Pin 6) is converted in current, with a 1/17.5k transconductance. Finally this current increases the voltage on Pin VLS (Pin 1) and allo ws t h e o u t pu t vo lt ag e, VPP(LSOUT) on Pin LSOUT (Pin 44) to increase. At low VRING input voltage, Pin VLS (Pin 1) is clamped at a 3V minimum voltage, to maintain a p ro p e r s u p ply t o t h e microc o n t ro lle r o n Pin VRMC (Pin 8), and the output voltage on Pin LSOUT(Pin 44) is progressively reduced. When the VRING input voltage increases, the Pin VLS (Pin 1) increases up to 6V and is clamped to 6V by an internal zener.
RCO (Pin 41) VPP (LSOUT) VLS (Pin 1)
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TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
VI - RINGER FEATURES (continued) VI.6 - Ring Software To generate the ring on the loudspeaker, the flowchart is in Figure 72. Figure 72
ON-HOOK
RI = 1 Yes RING START 0010 001
No
RING MODE
GROUP LISTENING CODE 0110 001 Default : Gmax -28dB (0 1 0 0 0 0 0) VOLUME CONTROL CODE 0 1 0 0 X X X or 0 1 1 1 0 1 1
VOLUME CHANGE No
Yes
Fi1 Code + Divider 1 Code 0 0 0 XX X X + 1 XX XX XX
Fi2 Code + Divider 2 Code 0 0 0 XX X X + 1 XX XX XX
FiN Code + Divider N Code 0 0 0 XX X X + 1 XX XX XX
RI = 1 No PON = 1 Yes INIT CODE 0101 000
Yes
No
ON-HOOK STEADY STATE
OFF-HOOK WITH DEFAULT CONDITIONS
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AN848-73.EPS
TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
VII - APPLICATION DIAGRAM
VL1 C8 CR1 D1 R9 R10 RETURN LOSS R16 C16 AGND HFIN PON
22 21 20 19 18 17 16 15 14 13 12
R11a
R11b
R27
R28 C28
R29 AGND C5
AGND C14
C9
SIDETONE R13 R5 R6 DATA C25 C27 C12 CLK
R15
R8
SNSL
REOUT
RECIN
DATA
HFIN
ASC
SNLL
ASQ
GTR
CLK
VREF
MIC+ C31 MICR21 C3 R4
23 MIC1 24 MIC2 25 VREF 26 VCC 27 TSOFT
RESET 11 RI/VI 10 OSC 9 VRMC 8 3.58MHz AGND C13 +
PON
RESET RI/VI
V RMC C15
TEA7092
DTMF1 7 LSSOF 6 LSIN 5 VREFL 4 VL 3 VMC 2 LSOUT DTMF2
29 IREF
R31 C20
R2 + C11 R18 R3
30 VS 31 SLPE 32 AGND
C19
R12
R1
28 SOFTL
+ C10 + C1
VMC
GREC
33 ILL
VLS 1
EAR+
EAR-
SWP
RCO
EAR+ EAR-
+ C24
R19
34
35
36
37
38
39
40
41
42
43
GND
RSU
I SL
VZP
44
+ R37 R35 C32 C2 LS AMPLIFLIER VREF
AGND
C17
R17 + C6 R14 R32 T1 L1 D2 D3 T2 R23 D7 C26 W1 R36 C30 R38 R40 C4 RING
LS1
Rx GAIN RING1
VLS
AN848-74.EPS
GND REOUT
LSIN
Ref. R1 R2 R3 R4 R5 R6 R8 R10 R11a R11b R12 R13 R14
Part 56k 30k 2.7k 820k 0 39k 1.62k 680 24 6.2 100k 2.7k 47k
Ref. R15 R16 R17 R18 R19 R21 R27 R28 R29 R31 R32 R33 R35
Part 2.2k 330k 75k 18k 6.8k 1.5k 3.3k 33k 18k 560k 220k 1.5k 56k
Ref. R36 R37 R38 R40
D1 D2 D3 D7 T1 T2
Part 4.7k 200k 150k 47k (50Hz/50)* 47k (25Hz/50)* 39k (50Hz/32)* 33k (25Hz/32)* 13V 47V 8.2V 1N4148 BC556B BC546B
Ref. L1 Q1 C1 C2 C3 C4 C5 C6 C8 C10 C11 C12 C13
Part 1mH 3,58MHz 100F 47F 150nF 220nF 560pF 10F (63V) 47F 470F 1F 100nF 47nF
Ref. C14 C15 C16 C17 C19 C20 C25 C26 C27 C28 C30 C31 C32 CR1
Part 47nF 4.7F 1F 330pF 470nF 47nF 470nF 47nF 100nF 1.8nF 1.2nF 10nF 2.7nF 10nF
* (Ring frequency / LS impedance)
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TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT
Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Microelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No licence is granted by implication or otherwise under any patent or patent rights of SGS-THOMSON Microelectronics. Specifications mentioned in this publication are subject to change without noti ce. This publication supersedes and replaces all information previously supplied. SGS-THOMSON Microelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of SGS-THOMSON Microelectronics. (c) 1996 SGS-THOMSON Microelectronics - All Rights Reserved Purchase of I2C Components of SGS-THOMSON Microelectronics, conveys a license under the Philips I2C Patent. Rights to use these components in a I2C system, is granted provided that the system confo rms to the I2C Standard Specifications as defined by Philips. SGS-THOMSON Microelectronics GROUP OF COMPANIES Australia - Brazil - Canada - China - France - Germany - Hong Kong - Italy - Japan - Korea - Malaysia - Malta - Morocco The Netherlands - Singapore - Spain - Sweden - Switzerland - Taiwan - Thailand - United Kingdom - U.S.A.
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