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DEMOBOARD
ECONOMY NICAM APPLICATION BOARD
1. INTRODUCTION The SGS-Thomson NICAM stereo decoder kit comprises two integrated circuits, namely the TDA8204 and TDA8205. Together they form a comprehensive architechure including not only the QPSK demodulation and NICAM decoding, but also the DAC circuitry (including audio filters), and an audio switching matrix to interface with the SCART connnector and auxilliary mono FM sound input. The kit is able to automatically synchronise with either system I or B/G NICAM signals, without adjustments of any kind, and requiring the use of only one quartz crystal. The architechture of the kit is such that, not only does it provide a comprehensivesolution for highend CTV applications, but it is also very economical for low-end applications. This is due to the high level of integration employed, requiring only about 40 externalcomponents to obtain a complete basic standalone NICAM application. The objective therefore of the Economy NICAM Application Board, is to present the TDA8204 and TDA8205 in a very compact application. As a result, certain features of the kit are deliberately not provided for, such as SCART interface and automatic dual-standard operation. The kit is normally controlled via the I2C bus, but is totally automatic even without any bus control. Thus the board is completely operational from power-up. Even so the Economy NICAM board has been provided with connections to the I2C bus terminals of the TDA8204 in order to retain access to certain of the inbuilt device features. A complete parts list and bill of materials has been provided in the appendix at the end of this document. 2. SET-UP Connect a 6.552MHz (or 5.85MHz) QPSK I/P signal of nominal level 100mVPP (40dB AGC range) to CN1. Power supplies are +5V for VDD and +12V for the VCC via the power connector CN2. Switch on both supplies together or +12V first.
AN636/0293
Audio outputs are available on CN4 (500mVRMS nom.). In addition, the FM backupinput (500mVRMS nom.) is also applied to CN4. CN3 provides the possibility of access to the I2C bus, mute and RSW functions of the TDA8204. 3. OPERATION The power on default modes for the decoder are AUT_STD = ON and AUTO_NICAM = ON. In this case, the decoder automatically synchronises with the transmission standard in use (system I or system B/G). FM backup sound is selected if no NICAM signal is present. If a NICAM signal is present and then removed and the Reserve Sound Flag (C4) was set to 1, the decoder will select FM sound. If C4 = 0, the audio outputs are muted. The Economy NICAM Application Board has been fitted with only one QPSK filter, for mono-standard applications. However all that is needed to convert from system I to system B/G, is to change the filter for the appropriate B/G version, no further adjustments being needed. The transmission mode is indicated by 3 LED's : - LED4 = Stereo (RED) - LED3 = Dual-Mono (RED) - LED2 = Single-Mono (RED) If no LED lights, either the mode is Data Only or the decoder is out of alignment. For Stereo and Single Mono modes, FM backup is provided for both audio outputs. For Dual Mono, FM backup is only for M1. 4. APPLICATION NOTES A layout of the application board is shown in Figure 1, enabling the user to identify the positions of all of the components. Figure 2 shows the circuit diagram of the application board. Several optional modifications can be made to the circuit as described in the following notes. Reference should be made to the data sheets of the TDA8204 and TDA8205 for full details of their implementation. The common connection to the three LEDs 2,3,4 can include a resistor if desired to reduce the
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ECONOMY NICAM APPLICATION BOARD
brightness of the LED. The link to place this resistor is located adjacent to LED4. LK1 and LK2 provide the possibility to force the language select option, in bi-lingual mode, via the SEL0 and SEL1 pins of the TDA8204. The board is supplied with both SEL pins connected to ground Figure 1 : Economy NICAM PCB Layout
MUTE
(ie normal stereo/mono mode). LK3 provides the possibility to force the RSW function on-board. The mute input on CN3 is bi-directional, and indicates or activates the DAC mute status. An indication of this status is shown by the yellow LED1.
R
SEL 0
LK1 SEL 1
C12
C19
X1
R10
C 11
C10
LK2
C16
C24
C25
C20
C21
LED1
R16
C17
ERROR MONITOR
R17
R9
C8
R8
C9
IC1
IC2
TDA8205
C5
TDA 8204
C8 DF 2
DF1
F1 6.552MHz
C1 3
C7
R13
C1 8 C23 C14 C15
C4
IN NICAM FILTER
C3 TR 1
OUT
R7 R4 R2 R1
R12 R11 R15 R14
LK3
LED4 LED3 LED2
R5
C2
ECONOMY-NICAM APPLICATION (V1.1)
POWER
C22 CN2
INPUT
CN1
CONTROL
C N3
AUDIO INTERFACE
CN4
C1
R6
R3
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AN636-01.EPS / AN636-02.TIF
CN4
FM MONO IN
O/P RIGHT ANALOG GND ANALOG GND C19 100nF C25 1F LK2 LK1 O/P LEFT
C12 47pF
X1 11.648MHz
ERROR MONITOR
C20 10F
C21 10 F
C11 150pF
C24 1F
LED1
R17 330 mute
R10 100k
C10 6.8nF
R9 8.2M
DV LF1 LF2 AIR
NDI
42 XK1
41
40
39
38
37
36
35
34
33 AOL DC2 CAP DC1 AOR
ND O
32 GND V DD ADV TEST SEL0
31
30
29
28
27
26
25
24 TEST SEL1
CK7 2 8
23 CK728 TEST2 TEST1 CK11648
22
1
2
3
4
5
6
7
8
9
10
11
12
13 14 FID PDV
15 DDO
16
DDI
17 GND
18 MUTE
19 RESET
20 ER
21 GND
EAIL
V CC1
SAIR
SAIL
MAI
C7 100nF
C8 220nF
C9 120pF
AM OR
AMOL
AGND2
MMO
Figure 2 : Economy NICAM Application Circuit
IC1
AGND1 XC1 XC2 DF2 DF1 BG IN
TDA8205
AV DD LFIL1
RG
IC2
RFIL1 RESET V DD SERI
DA C D L
TDA8204
US1 US0 SCL SDA SD SCK
WS
I IN
AGC
V CC2
AGND3
DACDR
DGN D
CK11648
GND
DA C D R
DA C D L
SER I
V DD
RS W
HA0
TEST 0
US2
V DD
C4
C3
C2 35 34 33 32 31 30 29 28 27 26 25 24 23 C18 100nF
R8 150
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
42
41
40
39
38
37
36
22
C1 LED2 single mono LED3 dual mono LED4 stereo
DF1 DF2 C4 10nF
C13 100nF
R11 3.3k
R1 8.2k
R4 470
F1 6.552MHz
C17 100nF
C3 10nF
C1 10nF
R2 47 R13 43k R14 43k R7 470 R12 5.6k
C5 C14 6.8nF 6.8nF C15 220pF 220pF C6
BFP
TR1
R16 100k
LK3
R3 1.2k
C2
CN1
R5 100
R6 33
10nF
C23 10F C22 10F
CN2 V CC V DD
SYS I
CN3
IN
RSW
SCL
SDA
C16 220 F
MUTE
ZTX108
R16 5.6k
ECONOMY NICAM APPLICATION BOARD
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AN636-03.EPS
ECONOMY NICAM APPLICATION BOARD
5. ADDENDUM TO THE NICAM DEMOBOARD NOTES Component Choice The components chosen for this application board have been selected on the basis of their size rather than specific need. There are no critical characteristic requirements for any of the components other than the capacitor C12. The value of this capacitor is simply chosen to match the particular quartz crystal source purchased. Voltage ratings of capacitors will be those appropriate to the total system, 16V types usually being sufficient in most cases. Two improvements are possible to the application circuit if neccessary and may be needed principally by system B/G with its closer wanted/unwanted carrier spacing. Details are as follows: 1) In system B/G mode, a 5.5MHz ceramic filter can be used to attenuate the FM sound by about 20dB with very little eye-diagram degradation. No provision is made on the application board for this filter. 2) A baseband L-C notch filter tuned to 350KHz can be fitted on DF1/2 pins by replacing the links in series with C5,6 (adjacent to the DF1 and DF2 monitor points), by inductors of 820%H (Toko style 7BS). 6. APPENDIX TO THE ECONOMY NICAM APPLICATION BOARD NOTES 6.1.Bill Of Materials 6.1.1. CAPACITORS (all rated at 16V)
Reference C1 C2 C3 C4 C5 C6 C7 C8 C9 C10 C11 C12 C13 C14 C15 C16 C17 C18 4/5 Value 10nF 10nF 10nF 10nF 220pF 220pF 100nF 220nF 120pF 6.8nF 150pF 47pF 100nF 6.8nF 6.8nF 220F 100nF 100nF Type Monolithic Ceramic Monolithic Ceramic Monolithic Ceramic Monolithic Ceramic Ceramic Plate Ceramic Plate Monolithic Ceramic Polyester Ceramic Plate Polyester Ceramic Plate Ceramic Plate Monolithic Ceramic Polyester Polyester Electrolytic Monolithic Ceramic Monolithic Ceramic Reference C19 C20 C21 C22 C23 C24 C25 Value 100nF 10F 10F 10F 10F 1F 1F Type Monolithic Ceramic Tantalum Bead Tantalum Bead Tantalum Bead Tantalum Bead Tantalum Bead Tantalum Bead
6.1.2. LIGHT EMITTING DIODES (low current type)
Reference LED1 LED2 LED3 LED4 Colour Yellow Red Red Red Function Indication Audio Muted Single Mono Transmission Dual Mono Transmission Stereo Transmission
6.1.3. FILTERS
Reference Frequency F1 6.552MHz TYpe TOKO 5VFP TH316BQM2110QDAF
6.1.4. INTEGRATED CIRCUITS
Reference Type IC1 TDA8205 IC2 TDA8204 Function QPSK, DAC and Audio Matrix 2 NICAM Decoder and I S Bus Output
6.1.5. TRANSISTORS
Reference TR1 Type ZTX108 Function 6.552MHz Filter Input Buffer
6.1.6 . RESISTORS (all 1/8W carbon film and values in 2)
Reference R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 Value 8.2k 47 1.2k 470 100 33 470 150 8.2M 180k 3.3k 5.6k 43k 43k 5.6k 100k 330
ECONOMY NICAM APPLICATION BOARD
6.1.7. QUARTZ CRYSTALS
Reference X1 Frequency 11.648MHz, Series Resonant with 30pF HC49U Package
6.2.4. INTEGRATED CIRCUITS
Type TDA8204 TDA8205 Quantity 1 1
6.1.8. CONNECTORS
Reference CN1 CN2 CN3 CN4 Type 2-way 5-way 5-way 5-way Function Sound IF Input Power Input Control Input/Output Audio Input/Output
6.2.5. TRANSISTORS
Type ZTX108 Quantity 1
6.2.6. QUARTZ CRYSTALS
Frequency 11.648MHz Quantity 1
6.2. Component Purchase List 6.2.1.CAPACITORS
Value 47pF 120pF 150pF 220pF 6.8nF 10nF 100nF 220nF 10F 220F Type Ceramic Plate Ceramic Plate Ceramic Plate Ceramic Plate Polyester Monolithic Ceramic Monolithic Ceramic Polyester Tantalum Bead Electrolytic Quantity 1 1 1 2 3 4 5 1 4 1
6.2.7. RESISTORS
Value 33 47 100 150 330 470 1.2k 3.3k 5.6k 8.2k 43k 100k 180k 8.2M Quantity 1 1 1 1 1 2 1 1 2 1 2 1 1 1
6.2.2. LIGHT EMITTING DIODES
Colour Red Yellow Quantity 3 1
6.2.8 CONNECTORS
Type 2-way Header 5-way Header Quantity 1 3
6.2.3. FILTERS
Type TOKO 5VFP TH3167BQM2110QDAF Quantity 1
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 notice. 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) 1994 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 conforms to the I2C Standard Specifications as defined by Philips. SGS-THOMSON Microelectronics GROUP OF COMPANIES Australia - Brazil - 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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