View PCA9550TK_4135664.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

PCA9550
2-bit I2C-bus LED driver with programmable blink rates
Rev. 04 -- 7 January 2008 Product data sheet
1. General description
The PCA9550 LED blinker blinks LEDs in I2C-bus and SMBus applications where it is necessary to limit bus traffic or free up the I2C Master's (MCU, MPU, DSP, chip set, etc.) timer. The uniqueness of this device is the internal oscillator with two programmable blink rates. To blink LEDs using normal I/O expanders like the PCF8574 or PCA9554, the bus master must send repeated commands to turn the LED on and off. This greatly increases the amount of traffic on the I2C-bus and uses up one of the master's timers. The PCA9550 LED blinker instead requires only the initial set-up command to program BLINK RATE 1 and BLINK RATE 2 (i.e., the frequency and duty cycle). From then on, only one command from the bus master is required to turn each individual open-drain output ON, OFF, or to cycle at BLINK RATE 1 or BLINK RATE 2. Maximum output sink current is 25 mA per bit and 50 mA per package. Any bits not used for controlling the LEDs can be used for General Purpose parallel Input/Output (GPIO) expansion. The active LOW hardware reset pin (RESET) and Power-On Reset (POR) initializes the registers to their default state, all zeroes, causing the bits to be set HIGH (LED off). One hardware address pin on the PCA9550 allows two devices to operate on the same bus.
2. Features
I 2 LED drivers (on, off, flashing at a programmable rate) I 2 selectable, fully programmable blink rates (frequency and duty cycle) between 0.172 Hz and 44 Hz (5.82 seconds and 0.023 second) I Input/output not used as LED drivers can be used as regular GPIOs I Internal oscillator requires no external components I I2C-bus interface logic compatible with SMBus I Internal power-on reset I Noise filter on SCL/SDA inputs I Active LOW reset input I 2 open-drain outputs directly drive LEDs to 25 mA I Controlled edge rates to minimize ground bounce I No glitch on power-up I Supports hot insertion I Low standby current I Operating power supply voltage range of 2.3 V to 5.5 V I 0 kHz to 400 kHz clock frequency
NXP Semiconductors
PCA9550
2-bit I2C-bus LED driver with programmable blink rates
I ESD protection exceeds 2000 V HBM per JESD22-A114, 150 V MM per JESD22-A115 and 1000 V CDM per JESD22-C101 I Latch-up testing is done to JEDEC Standard JESD78 which exceeds 100 mA I Packages offered: SO8, TSSOP8 (MSOP8), HVSON8
3. Ordering information
Table 1. Ordering information Package Name PCA9550D PCA9550DP PCA9550TK SO8 TSSOP8[1] HVSON8 Description plastic small outline package; 8 leads; body width 3.9 mm plastic thin shrink small outline package; 8 leads; body width 3 mm Version SOT96-1 SOT505-1 Type number
plastic thermal enhanced very thin small outline package; no leads; 8 terminals; SOT908-1 body 3 x 3 x 0.85 mm
[1]
Also known as MSOP8.
3.1 Ordering options
Table 2. PCA9550D PCA9550DP PCA9550TK Ordering options Topside mark PCA9550 9550 9550 Temperature range Tamb = -40 C to +85 C Tamb = -40 C to +85 C Tamb = -40 C to +85 C Type number
4. Block diagram
A0
PCA9550
INPUT REGISTER I2C-BUS CONTROL LED SELECT (LS0) REGISTER
SCL SDA
INPUT FILTERS
0 VDD RESET 1 PRESCALER 0 REGISTER OSCILLATOR VSS PRESCALER 1 REGISTER PWM0 REGISTER PWM1 REGISTER BLINK0 BLINK1
POWER-ON RESET
LEDn
002aad241
Only one I/O shown for clarity.
Fig 1. Block diagram of PCA9550
PCA9550_4
(c) NXP B.V. 2008. All rights reserved.
Product data sheet
Rev. 04 -- 7 January 2008
2 of 26
NXP Semiconductors
PCA9550
2-bit I2C-bus LED driver with programmable blink rates
5. Pinning information
5.1 Pinning
A0 LED0 LED1 VSS
1 2
8 7
VDD SDA SCL RESET
A0 LED0 LED1 VSS
1 2 3 4
002aad239
8 7
VDD SDA SCL RESET
PCA9550D
3 4
002aad238
6 5
PCA9550DP
6 5
Fig 2. Pin configuration for SO8
terminal 1 index area
Fig 3. Pin configuration for TSSOP8
A0 LED0 LED1 VSS
1 2
8 7
VDD SDA SCL RESET
PCA9550TK
3 4 6 5
002aad240
Transparent top view
Fig 4. Pin configuration for HVSON8
5.2 Pin description
Table 3. Symbol A0 LED0 LED1 VSS RESET SCL SDA VDD Pin description Pin 1 2 3 4 5 6 7 8 Description address input 0 LED driver 0 LED driver 1 supply ground active LOW reset input serial clock line serial data line supply voltage
PCA9550_4
(c) NXP B.V. 2008. All rights reserved.
Product data sheet
Rev. 04 -- 7 January 2008
3 of 26
NXP Semiconductors
PCA9550
2-bit I2C-bus LED driver with programmable blink rates
6. Functional description
Refer to Figure 1 "Block diagram of PCA9550".
6.1 Device address
Following a START condition, the bus master must output the address of the slave it is accessing. The address of the PCA9550 is shown in Figure 5. To conserve power, no internal pull-up resistor is incorporated on the hardware selectable address pin and it must be pulled HIGH or LOW.
slave address 1 1 0 0 0 0 A0 R/W
fixed
hardware selectable
002aad242
Fig 5. PCA9550 slave address
The last bit of the address byte defines the operation to be performed. When set to logic 1 a read is selected, while a logic 0 selects a write operation.
6.2 Control register
Following the successful acknowledgement of the slave address, the bus master will send a byte to the PCA9550, which will be stored in the Control register.
0
0
0
AI
0
B2
B1
B0
Auto-Increment flag
register address
002aad243
Reset state: 00h
Fig 6. Control register
The lowest 3 bits are used as a pointer to determine which register will be accessed. If the Auto-Increment (AI) flag is set, the three low order bits of the Control register are automatically incremented after a read or write. This allows the user to program the registers sequentially. The contents of these bits will rollover to `000' after the last register is accessed. When the Auto-Increment flag is set (AI = 1) and a read sequence is initiated, the sequence must start by reading a register different from the input register (B2 B1 B0 000). Only the 3 least significant bits are affected by the AI flag. Unused bits must be programmed with zeroes.
PCA9550_4
(c) NXP B.V. 2008. All rights reserved.
Product data sheet
Rev. 04 -- 7 January 2008
4 of 26
NXP Semiconductors
PCA9550
2-bit I2C-bus LED driver with programmable blink rates
6.2.1 Control register definition
Table 4. B2 0 0 0 0 1 1 B1 0 0 1 1 0 0 Register summary B0 0 1 0 1 0 1 Register name INPUT PSC0 PWM0 PSC1 PWM1 LS0 Access read only read/write read/write read/write read/write read/write Description input register frequency prescaler 0 PWM register 0 frequency prescaler 1 PWM register 1 LED selector
6.3 Register descriptions
6.3.1 INPUT - Input register
The INPUT register reflects the state of the device pins. Writes to this register will be acknowledged but will have no effect.
Table 5. Bit Symbol Default 0 0 0 INPUT - Input register description 7 6 5 not used 0 0 0 4 3 2 1 LED1 X 0 LED0 X
Remark: The default value `X' is determined by the externally applied logic level (normally logic 1) when used for directly driving LED with pull-up to VDD.
6.3.2 PSC0 - Frequency Prescaler 0
PSC0 is used to program the period of the PWM output. The period of BLINK0 = (PSC0 + 1) / 44.
Table 6. Bit Symbol Default PSC0 - Frequency Prescaler 0 register description 7 PSC0[7] 1 6 PSC0[6] 1 5 PSC0[5] 1 4 PSC0[4] 1 3 PSC0[3] 1 2 PSC0[2] 1 1 PSC0[1] 1 0 PSC0[0] 1
6.3.3 PWM0 - Pulse Width Modulation 0
The PWM0 register determines the duty cycle of BLINK0. The outputs are LOW (LED off) when the count is less than the value in PWM0 and HIGH when it is greater. If PWM0 is programmed with 00h, then the PWM0 output is always LOW. The duty cycle of BLINK0 = (256 - PWM0) / 256.
Table 7. Bit Symbol Default PWM0 - Pulse Width Modulation 0 register description 7 PWM0 [7] 1 6 PWM0 [6] 0 5 PWM0 [5] 0 4 PWM0 [4] 0 3 PWM0 [3] 0 2 PWM0 [2] 0 1 PWM0 [1] 0 0 PWM0 [0] 0
PCA9550_4
(c) NXP B.V. 2008. All rights reserved.
Product data sheet
Rev. 04 -- 7 January 2008
5 of 26
NXP Semiconductors
PCA9550
2-bit I2C-bus LED driver with programmable blink rates
6.3.4 PSC1 - Frequency Prescaler 1
PSC1 is used to program the period of the PWM output. The period of BLINK1 = (PSC1 + 1) / 44.
Table 8. Bit Symbol Default PSC1 - Frequency Prescaler 1 register description 7 PSC1[7] 1 6 PSC1[6] 1 5 PSC1[5] 1 4 PSC1[4] 1 3 PSC1[3] 1 2 PSC1[2] 1 1 PSC1[1] 1 0 PSC1[0] 1
6.3.5 PWM1 - Pulse Width Modulation 1
The PWM1 register determines the duty cycle of BLINK1. The outputs are LOW (LED off) when the count is less than the value in PWM1 and HIGH when it is greater. If PWM1 is programmed with 00h, then the PWM1 output is always LOW. The duty cycle of BLINK1 = (256 - PWM1) / 256.
Table 9. Bit Symbol Default PWM1 - Pulse Width Modulation 1 register description 7 PWM1 [7] 1 6 PWM1 [6] 0 5 PWM1 [5] 0 4 PWM1 [4] 0 3 PWM1 [3] 0 2 PWM1 [2] 0 1 PWM1 [1] 0 0 PWM1 [0] 0
6.3.6 LS0 - LED selector
The LS0 LED select register determines the source of the LED data. 00 = output is set LOW (LED on) 01 = output is set high-impedance (LED off; default) 10 = output blinks at PWM0 rate 11 = output blinks at PWM1 rate
Table 10. Bit Symbol Default 1 1 LS0 - LED selector register description 7 6 LS0[7:4] 1 1 0 5 4 3 LED1 1 0 2 1 LED0 1 0
PCA9550_4
(c) NXP B.V. 2008. All rights reserved.
Product data sheet
Rev. 04 -- 7 January 2008
6 of 26
NXP Semiconductors
PCA9550
2-bit I2C-bus LED driver with programmable blink rates
6.4 Pins used as GPIOs
LED pins not used to control LEDs can be used as General Purpose Input/Outputs (GPIOs). For use as input, set LEDn to high-impedance (01) and then read the pin state via the Input register. For use as output, connect external pull-up resistor to the pin and size it according to the DC recommended operating characteristics. LEDn output pin is HIGH when the output is programmed as high-impedance, and LOW when the output is programmed LOW through the LED selector register (LS0). The output can be pulse-width controlled when PWM0 or PWM1 are used.
6.5 Power-on reset
When power is applied to VDD, an internal Power-On Reset (POR) holds the PCA9550 in a reset condition until VDD has reached VPOR. At that point, the reset condition is released and the PCA9550 registers are initialized to their default states, all the outputs in the OFF state. Thereafter, VDD must be lowered below 0.2 V to reset the device.
6.6 External RESET
A reset can be accomplished by holding the RESET pin LOW for a minimum of tw(rst). The PCA9550 registers and I2C-bus state machine will be held in their default states until the RESET input is once again HIGH. This input requires a pull-up resistor to VDD if no active connection is used.
PCA9550_4
(c) NXP B.V. 2008. All rights reserved.
Product data sheet
Rev. 04 -- 7 January 2008
7 of 26
NXP Semiconductors
PCA9550
2-bit I2C-bus LED driver with programmable blink rates
7. Characteristics of the I2C-bus
The I2C-bus is for 2-way, 2-line communication between different ICs or modules. The two lines are a serial data line (SDA) and a serial clock line (SCL). Both lines must be connected to a positive supply via a pull-up resistor when connected to the output stages of a device. Data transfer may be initiated only when the bus is not busy.
7.1 Bit transfer
One data bit is transferred during each clock pulse. The data on the SDA line must remain stable during the HIGH period of the clock pulse as changes in the data line at this time will be interpreted as control signals (see Figure 7).
SDA
SCL data line stable; data valid change of data allowed
mba607
Fig 7. Bit transfer
7.1.1 START and STOP conditions
Both data and clock lines remain HIGH when the bus is not busy. A HIGH-to-LOW transition of the data line while the clock is HIGH is defined as the START condition (S). A LOW-to-HIGH transition of the data line while the clock is HIGH is defined as the STOP condition (P) (see Figure 8.)
SDA
SDA
SCL S START condition P STOP condition
SCL
mba608
Fig 8. Definition of START and STOP conditions
7.2 System configuration
A device generating a message is a `transmitter'; a device receiving is the `receiver'. The device that controls the message is the `master' and the devices which are controlled by the master are the `slaves' (see Figure 9).
PCA9550_4
(c) NXP B.V. 2008. All rights reserved.
Product data sheet
Rev. 04 -- 7 January 2008
8 of 26
NXP Semiconductors
PCA9550
2-bit I2C-bus LED driver with programmable blink rates
SDA SCL MASTER TRANSMITTER/ RECEIVER SLAVE RECEIVER SLAVE TRANSMITTER/ RECEIVER MASTER TRANSMITTER MASTER TRANSMITTER/ RECEIVER I2C-BUS MULTIPLEXER
SLAVE
002aaa966
Fig 9. System configuration
7.3 Acknowledge
The number of data bytes transferred between the START and the STOP conditions from transmitter to receiver is not limited. Each byte of eight bits is followed by one acknowledge bit. The acknowledge bit is a HIGH level put on the bus by the transmitter, whereas the master generates an extra acknowledge related clock pulse. A slave receiver which is addressed must generate an acknowledge after the reception of each byte. Also a master must generate an acknowledge after the reception of each byte that has been clocked out of the slave transmitter. The device that acknowledges has to pull down the SDA line during the acknowledge clock pulse, so that the SDA line is stable LOW during the HIGH period of the acknowledge related clock pulse; set-up and hold times must be taken into account. A master receiver must signal an end of data to the transmitter by not generating an acknowledge on the last byte that has been clocked out of the slave. In this event, the transmitter must leave the data line HIGH to enable the master to generate a STOP condition.
data output by transmitter not acknowledge data output by receiver acknowledge SCL from master S START condition 1 2 8 clock pulse for acknowledgement
002aaa987
9
Fig 10. Acknowledgement on the I2C-bus
PCA9550_4
(c) NXP B.V. 2008. All rights reserved.
Product data sheet
Rev. 04 -- 7 January 2008
9 of 26
NXP Semiconductors
PCA9550
2-bit I2C-bus LED driver with programmable blink rates
7.4 Bus transactions
SCL
1
2
3
4
5
6
7
8
9 command byte data to register DATA 1 A acknowledge from slave
slave address SDA S 1 1 0 0 0 0 A0 0 R/W A 0 0
0
AI
0 B2 B1 B0 A acknowledge from slave
START condition write to register
acknowledge from slave
tv(Q) data out from port DATA 1 VALID
002aad268
Fig 11. Write to register
slave address SDA S 1 1 0 0 0 0 A0 0 R/W A 0 0
command byte 0 AI 0 B2 B1 B0 A acknowledge from slave data from register A DATA (first byte) Auto-Increment register address if AI = 1 A acknowledge from master data from register DATA (last byte) NA P STOP condition (cont.)
START condition
acknowledge from slave slave address (cont.) S 1 1 0 0 0 0 A0 1 R/W acknowledge from slave
(repeated) START condition
no acknowledge from master
at this moment master-transmitter becomes master-receiver and slave-receiver becomes slave-transmitter
002aad269
Fig 12. Read from register
no acknowledge from master slave address SDA S 1 1 0 0 0 0 A0 1 R/W A acknowledge from slave data from port DATA 1 A acknowledge from master data from port DATA 4 NA P STOP condition
START condition
read from port th(D) data into port DATA 1 DATA 2 DATA 3 tsu(D) DATA 4
002aad270
Remark: This figure assumes the command byte has previously been programmed with 00h.
Fig 13. Read input port register
PCA9550_4
(c) NXP B.V. 2008. All rights reserved.
Product data sheet
Rev. 04 -- 7 January 2008
10 of 26
NXP Semiconductors
PCA9550
2-bit I2C-bus LED driver with programmable blink rates
8. Application design-in information
5V
5V
10 k
10 k
10 k
I2C-BUS/SMBus MASTER SDA SCL
VDD
PCA9550
SDA SCL LED0 LED1
RESET A0 VSS
002aad271
Fig 14. Typical application
8.1 Minimizing IDD when the I/Os are used to control LEDs
When the I/Os are used to control LEDs, they are normally connected to VDD through a resistor as shown in Figure 14. Since the LED acts as a diode, when the LED is off the I/O VI is about 1.2 V less than VDD. The supply current, IDD, increases as VI becomes lower than VDD and is specified as IDD in Table 13 "Static characteristics". Designs needing to minimize current consumption, such as battery power applications, should consider maintaining the I/O pins greater than or equal to VDD when the LED is off. Figure 15 shows a high value resistor in parallel with the LED. Figure 16 shows VDD less than the LED supply voltage by at least 1.2 V. Both of these methods maintain the I/O VI at or above VDD and prevents additional supply current consumption when the LED is off.
VDD
3.3 V
5V
VDD
LED
100 k
VDD
LED
LEDn
LEDn
002aac189
002aac190
Fig 15. High value resistor in parallel with the LED
Fig 16. Device supplied by a lower voltage
PCA9550_4
(c) NXP B.V. 2008. All rights reserved.
Product data sheet
Rev. 04 -- 7 January 2008
11 of 26
NXP Semiconductors
PCA9550
2-bit I2C-bus LED driver with programmable blink rates
8.2 Programming example
The following example will show how to set LED0 to blink at 1 Hz at a 50 % duty cycle. LED1 will be set to blink at 4 Hz and at a 25 % duty cycle.
Table 11. START PCA9550 address with A0 = LOW PSC0 subaddress + Auto-Increment Set prescaler PSC0 to achieve a period of 1 second: PSC0 + 1 Blink period = 1 = ----------------------44 PSC0 = 43 Set PWM0 duty cycle to 50 %: 256 - PWM0 -------------------------------- = 0.5 256 PWM0 = 128 Set prescaler PSC1 to achieve a period of 0.25 seconds: PSC1 + 1 Blink period = 0.25 = ----------------------44 PSC1 = 10 Set PWM1 output duty cycle to 25 %: 256 - PWM1 -------------------------------- = 0.25 256 PWM1 = 192 Set LED0 to PWM0, and set LED1 to blink at PWM1 STOP 0Eh P C0h 0Ah 80h Programming PCA9550 I2C-bus S C0h 11h 2Bh
Program sequence
9. Limiting values
Table 12. Limiting values In accordance with the Absolute Maximum Rating System (IEC 60134). Symbol VDD VI/O IO(LEDn) ISS Ptot Tstg Tamb Parameter supply voltage voltage on an input/output pin output current on pin LEDn ground supply current total power dissipation storage temperature ambient temperature operating Conditions Min -0.5 VSS - 0.5 -65 -40 Max +6.0 5.5 25 50 400 +150 +85 Unit V V mA mA mW C C
PCA9550_4
(c) NXP B.V. 2008. All rights reserved.
Product data sheet
Rev. 04 -- 7 January 2008
12 of 26
NXP Semiconductors
PCA9550
2-bit I2C-bus LED driver with programmable blink rates
10. Static characteristics
Table 13. Static characteristics VDD = 2.3 V to 5.5 V; VSS = 0 V; Tamb = -40 C to +85 C; unless otherwise specified. Symbol Supplies VDD IDD Istb IDD supply voltage supply current standby current operating mode; VDD = 5.5 V; no load; VI = VDD or VSS; fSCL = 100 kHz Standby mode; VDD = 5.5 V; no load; VI = VDD or VSS; fSCL = 0 kHz 2.3 350 1.9 5.5 500 3.0 200 V A A A Parameter Conditions Min Typ[1] Max Unit
additional quiescent supply Standby mode; VDD = 5.5 V; current every LED I/O at VI = 4.3 V; fSCL = 0 kHz power-on reset voltage LOW-level input voltage HIGH-level input voltage LOW-level output current leakage current input capacitance LOW-level input voltage HIGH-level input voltage LOW-level output current VOL = 0.4 V VDD = 2.3 V VDD = 3.0 V VDD = 5.0 V VOL = 0.7 V VDD = 2.3 V VDD = 3.0 V VDD = 5.0 V
[3] [3] [3] [3] [3] [3]
VPOR VIL VIH IOL IL Ci I/Os VIL VIH IOL
no load; VI = VDD or VSS
[2]
1.4 -0.5 0.7VDD
1.7 6.5 3.7 2.1 2.3
2.2 +0.3VDD 5.5 +1 5 +0.8 5.5 +1 5 +0.8 5.5 +1 5
V V V mA A pF V V mA mA mA mA mA mA A pF V V A pF
Input SCL; input/output SDA
VOL = 0.4 V VI = VDD = VSS VI = VSS
3 -1 -0.5 2.0 9 11 14 14 18 24 -1 -0.5 2.0 -1
ILI Cio VIL VIH ILI Ci
[1] [2] [3]
input leakage current input/output capacitance LOW-level input voltage HIGH-level input voltage input leakage current input capacitance
VDD = 3.6 V; VI = 0 V or VDD
Select inputs A0; RESET
VI = VSS
-
Typical limits at VDD = 3.3 V, Tamb = 25 C. VDD must be lowered to 0.2 V in order to reset part. Each I/O must be externally limited to a maximum of 25 mA and the device must be limited to a maximum current of 50 mA.
PCA9550_4
(c) NXP B.V. 2008. All rights reserved.
Product data sheet
Rev. 04 -- 7 January 2008
13 of 26
NXP Semiconductors
PCA9550
2-bit I2C-bus LED driver with programmable blink rates
20 % percent variation 0%
002aac191
(1)
20 % percent variation 0%
002aac192
(1)
(2)
(2)
-20 %
(3)
-20 %
(3)
-40 % -40
-20
0
20
40
60
100 Tamb (C) 80
-40 % -40
-20
0
20
40
60
100 80 Tamb (C)
(1) maximum (2) average (3) minimum
(1) maximum (2) average (3) minimum
Fig 17. Typical frequency variation over process at VDD = 2.3 V to 3.0 V
Fig 18. Typical frequency variation over process at VDD = 3.0 V to 5.5 V
PCA9550_4
(c) NXP B.V. 2008. All rights reserved.
Product data sheet
Rev. 04 -- 7 January 2008
14 of 26
NXP Semiconductors
PCA9550
2-bit I2C-bus LED driver with programmable blink rates
11. Dynamic characteristics
Table 14. Symbol Dynamic characteristics Parameter Conditions Standard-mode I2C-bus Min fSCL tBUF tHD;STA tSU;STA tSU;STO tHD;DAT tVD;ACK tVD;DAT tSU;DAT tLOW tHIGH tr tf tSP Port timing tv(Q) tsu(D) th(D) Reset tw(rst) trec(rst) trst
[1] [2] [3] [4] [5]
Fast-mode I2C-bus Min 0 1.3 0.6 0.6 0.6 0 100 1.3 0.6 20 + 20 + 0.1Cb[3] 0.1Cb[3] Max 400 600 600 600 300 300 50
Unit
Max 100 600 600 1500 1000 300 50
SCL clock frequency bus free time between a STOP and START condition hold time (repeated) START condition set-up time for a repeated START condition set-up time for STOP condition data hold time data valid acknowledge time data valid time data set-up time LOW period of the SCL clock HIGH period of the SCL clock rise time of both SDA and SCL signals fall time of both SDA and SCL signals pulse width of spikes that must be suppressed by the input filter data output valid time data input set-up time data input hold time reset pulse width reset recovery time reset time
[4][5] [1]
0 4.7 4.0 4.7 4.0 0 250 4.7 4.0 LOW-level HIGH-level
[2] [2]
kHz s s s s ns ns ns ns ns s s ns ns ns
100 1 6 0 400
200 -
100 1 6 0 400
200 -
ns ns s ns ns ns
tVD;ACK = time for Acknowledgement signal from SCL LOW to SDA (out) LOW. tVD;DAT = minimum time for SDA data output to be valid following SCL LOW. Cb = total capacitance of one bus line in pF. Resetting the device while actively communicating on the bus may cause glitches or errant STOP conditions. Upon reset, the full delay will be the sum of trst and the RC time constant of the SDA bus.
PCA9550_4
(c) NXP B.V. 2008. All rights reserved.
Product data sheet
Rev. 04 -- 7 January 2008
15 of 26
NXP Semiconductors
PCA9550
2-bit I2C-bus LED driver with programmable blink rates
START SCL
ACK or read cycle
SDA 30 % trst
RESET
50 % trec(rst)
50 % tw(rst)
50 %
trst LEDn 50 % LED off
002aac193
Fig 19. Definition of RESET timing
SDA tBUF tLOW SCL tr tf tHD;STA tSP
tHD;STA P S tHD;DAT tHIGH tSU;DAT Sr
tSU;STA
tSU;STO P
002aaa986
Fig 20. Definition of timing
PCA9550_4
(c) NXP B.V. 2008. All rights reserved.
Product data sheet
Rev. 04 -- 7 January 2008
16 of 26
NXP Semiconductors
PCA9550
2-bit I2C-bus LED driver with programmable blink rates
protocol
START condition (S) tSU;STA
bit 7 MSB (A7) tLOW tHIGH
bit 6 (A6)
bit 0 (R/W)
acknowledge (A)
STOP condition (P)
1/f
SCL
SCL tBUF tr tf
SDA
tHD;STA
tSU;DAT
tHD;DAT
tVD;DAT
tVD;ACK
tSU;STO
002aab175
Rise and fall times refer to VIL and VIH.
Fig 21. I2C-bus timing diagram
12. Test information
VDD open VSS
VDD PULSE GENERATOR VI DUT
RT
VO
RL 500
CL 50 pF
002aab880
RL = load resistor for LEDn. RL for SDA and SCL > 1 k (3 mA or less current). CL = load capacitance includes jig and probe capacitance. RT = termination resistance should be equal to the output impedance Zo of the pulse generators.
Fig 22. Test circuitry for switching times
PCA9550_4
(c) NXP B.V. 2008. All rights reserved.
Product data sheet
Rev. 04 -- 7 January 2008
17 of 26
NXP Semiconductors
PCA9550
2-bit I2C-bus LED driver with programmable blink rates
13. Package outline
SO8: plastic small outline package; 8 leads; body width 3.9 mm SOT96-1
D
E
A X
c y HE vMA
Z 8 5
Q A2 A1 pin 1 index Lp 1 e bp 4 wM L detail X (A 3) A
0
2.5 scale
5 mm
DIMENSIONS (inch dimensions are derived from the original mm dimensions) UNIT mm inches Notes 1. Plastic or metal protrusions of 0.15 mm (0.006 inch) maximum per side are not included. 2. Plastic or metal protrusions of 0.25 mm (0.01 inch) maximum per side are not included. OUTLINE VERSION SOT96-1 REFERENCES IEC 076E03 JEDEC MS-012 JEITA EUROPEAN PROJECTION A max. 1.75 0.069 A1 0.25 0.10 A2 1.45 1.25 A3 0.25 0.01 bp 0.49 0.36 c 0.25 0.19 D (1) 5.0 4.8 0.20 0.19 E (2) 4.0 3.8 0.16 0.15 e 1.27 0.05 HE 6.2 5.8 L 1.05 Lp 1.0 0.4 Q 0.7 0.6 v 0.25 0.01 w 0.25 0.01 y 0.1 0.004 Z (1) 0.7 0.3 0.028 0.012
0.010 0.057 0.004 0.049
0.019 0.0100 0.014 0.0075
0.244 0.039 0.028 0.041 0.228 0.016 0.024
8o o 0
ISSUE DATE 99-12-27 03-02-18
Fig 23. Package outline SOT96-1 (SO8)
PCA9550_4 (c) NXP B.V. 2008. All rights reserved.
Product data sheet
Rev. 04 -- 7 January 2008
18 of 26
NXP Semiconductors
PCA9550
2-bit I2C-bus LED driver with programmable blink rates
TSSOP8: plastic thin shrink small outline package; 8 leads; body width 3 mm
SOT505-1
D
E
A
X
c y HE vMA
Z
8
5
A2 pin 1 index
A1
(A3)
A
Lp L
1
e bp
4
detail X wM
0
2.5 scale
5 mm
DIMENSIONS (mm are the original dimensions) UNIT mm A max. 1.1 A1 0.15 0.05 A2 0.95 0.80 A3 0.25 bp 0.45 0.25 c 0.28 0.15 D(1) 3.1 2.9 E(2) 3.1 2.9 e 0.65 HE 5.1 4.7 L 0.94 Lp 0.7 0.4 v 0.1 w 0.1 y 0.1 Z(1) 0.70 0.35 6 0
Notes 1. Plastic or metal protrusions of 0.15 mm maximum per side are not included. 2. Plastic or metal protrusions of 0.25 mm maximum per side are not included. OUTLINE VERSION SOT505-1 REFERENCES IEC JEDEC JEITA EUROPEAN PROJECTION ISSUE DATE 99-04-09 03-02-18
Fig 24. Package outline SOT505-1 (TSSOP8)
PCA9550_4 (c) NXP B.V. 2008. All rights reserved.
Product data sheet
Rev. 04 -- 7 January 2008
19 of 26
NXP Semiconductors
PCA9550
2-bit I2C-bus LED driver with programmable blink rates
HVSON8: plastic thermal enhanced very thin small outline package; no leads; 8 terminals; body 3 x 3 x 0.85 mm
SOT908-1
0
1 scale
2 mm
X
D
B
A
E
A A1 c detail X
terminal 1 index area terminal 1 index area
1
e1 e b
4
v w
M M
CAB C
C y1 C y exposed tie bar (4x)
L
Eh
exposed tie bar (4x)
8
5
Dh
DIMENSIONS (mm are the original dimensions) UNIT mm A(1) max. 1 A1 0.05 0.00 b 0.3 0.2 c 0.2 D(1) 3.1 2.9 Dh 2.25 1.95 E(1) 3.1 2.9 Eh 1.65 1.35 e 0.5 e1 1.5 L 0.5 0.3 v 0.1 w 0.05 y 0.05 y1 0.1
Note 1. Plastic or metal protrusions of 0.075 mm maximum per side are not included. OUTLINE VERSION SOT908-1 REFERENCES IEC JEDEC MO-229 JEITA EUROPEAN PROJECTION ISSUE DATE 05-09-26 05-10-05
Fig 25. Package outline SOT908-1 (HVSON8)
PCA9550_4 (c) NXP B.V. 2008. All rights reserved.
Product data sheet
Rev. 04 -- 7 January 2008
20 of 26
NXP Semiconductors
PCA9550
2-bit I2C-bus LED driver with programmable blink rates
14. Handling information
Inputs and outputs are protected against electrostatic discharge in normal handling. However, to be completely safe you must take normal precautions appropriate to handling integrated circuits.
15. Soldering
This text provides a very brief insight into a complex technology. A more in-depth account of soldering ICs can be found in Application Note AN10365 "Surface mount reflow soldering description".
15.1 Introduction to soldering
Soldering is one of the most common methods through which packages are attached to Printed Circuit Boards (PCBs), to form electrical circuits. The soldered joint provides both the mechanical and the electrical connection. There is no single soldering method that is ideal for all IC packages. Wave soldering is often preferred when through-hole and Surface Mount Devices (SMDs) are mixed on one printed wiring board; however, it is not suitable for fine pitch SMDs. Reflow soldering is ideal for the small pitches and high densities that come with increased miniaturization.
15.2 Wave and reflow soldering
Wave soldering is a joining technology in which the joints are made by solder coming from a standing wave of liquid solder. The wave soldering process is suitable for the following:
* Through-hole components * Leaded or leadless SMDs, which are glued to the surface of the printed circuit board
Not all SMDs can be wave soldered. Packages with solder balls, and some leadless packages which have solder lands underneath the body, cannot be wave soldered. Also, leaded SMDs with leads having a pitch smaller than ~0.6 mm cannot be wave soldered, due to an increased probability of bridging. The reflow soldering process involves applying solder paste to a board, followed by component placement and exposure to a temperature profile. Leaded packages, packages with solder balls, and leadless packages are all reflow solderable. Key characteristics in both wave and reflow soldering are:
* * * * * *
Board specifications, including the board finish, solder masks and vias Package footprints, including solder thieves and orientation The moisture sensitivity level of the packages Package placement Inspection and repair Lead-free soldering versus PbSn soldering
15.3 Wave soldering
Key characteristics in wave soldering are:
PCA9550_4 (c) NXP B.V. 2008. All rights reserved.
Product data sheet
Rev. 04 -- 7 January 2008
21 of 26
NXP Semiconductors
PCA9550
2-bit I2C-bus LED driver with programmable blink rates
* Process issues, such as application of adhesive and flux, clinching of leads, board
transport, the solder wave parameters, and the time during which components are exposed to the wave
* Solder bath specifications, including temperature and impurities 15.4 Reflow soldering
Key characteristics in reflow soldering are:
* Lead-free versus SnPb soldering; note that a lead-free reflow process usually leads to
higher minimum peak temperatures (see Figure 26) than a PbSn process, thus reducing the process window
* Solder paste printing issues including smearing, release, and adjusting the process
window for a mix of large and small components on one board
* Reflow temperature profile; this profile includes preheat, reflow (in which the board is
heated to the peak temperature) and cooling down. It is imperative that the peak temperature is high enough for the solder to make reliable solder joints (a solder paste characteristic). In addition, the peak temperature must be low enough that the packages and/or boards are not damaged. The peak temperature of the package depends on package thickness and volume and is classified in accordance with Table 15 and 16
Table 15. SnPb eutectic process (from J-STD-020C) Package reflow temperature (C) Volume (mm3) < 350 < 2.5 2.5 Table 16. 235 220 Lead-free process (from J-STD-020C) Package reflow temperature (C) Volume (mm3) < 350 < 1.6 1.6 to 2.5 > 2.5 260 260 250 350 to 2000 260 250 245 > 2000 260 245 245 350 220 220
Package thickness (mm)
Package thickness (mm)
Moisture sensitivity precautions, as indicated on the packing, must be respected at all times. Studies have shown that small packages reach higher temperatures during reflow soldering, see Figure 26.
PCA9550_4
(c) NXP B.V. 2008. All rights reserved.
Product data sheet
Rev. 04 -- 7 January 2008
22 of 26
NXP Semiconductors
PCA9550
2-bit I2C-bus LED driver with programmable blink rates
temperature
maximum peak temperature = MSL limit, damage level
minimum peak temperature = minimum soldering temperature
peak temperature
time
001aac844
MSL: Moisture Sensitivity Level
Fig 26. Temperature profiles for large and small components
For further information on temperature profiles, refer to Application Note AN10365 "Surface mount reflow soldering description".
16. Abbreviations
Table 17. Acronym AI CDM DSP DUT ESD GPIO HBM I2C-bus I/O LED MCU MM MPU POR PWM RC SMBus Abbreviations Description Auto-Increment Charged Device Model Digital Signal Processor Device Under Test ElectroStatic Discharge General Purpose Input/Output Human Body Model Inter-integrated Circuit bus Input/Output Light Emitting Diode Microcontroller Machine Model Microprocessor Power-On Reset Pulse Width Modulation Resistor-Capacitor network System Management Bus
PCA9550_4
(c) NXP B.V. 2008. All rights reserved.
Product data sheet
Rev. 04 -- 7 January 2008
23 of 26
NXP Semiconductors
PCA9550
2-bit I2C-bus LED driver with programmable blink rates
17. Revision history
Table 18. Revision history Release date 20080107 Data sheet status Product data sheet Change notice Supersedes PCA9550_3 Document ID PCA9550_4 Modifications:
* * * * * *
The format of this data sheet has been redesigned to comply with the new identity guidelines of NXP Semiconductors. Legal texts have been adapted to the new company name where appropriate. Added HVSON8 package offering (type number PCA9550TK). Section 6.6 "External RESET", first sentence: changed symbol "tW" to "tw(rst)" Figure 11 "Write to register": changed symbol "tpv" to "tv(Q)" Figure 13 "Read input port register": - changed symbol "tph" to "th(D)" - changed symbol "tps" to "tsu(D)"
* * *
Table 12 "Limiting values": changed "II/O, DC output current on an I/O" to "IO(LEDn), output current on pin LEDn" Table 13 "Static characteristics", sub-section "I/Os": changed symbol "IL" to "ILI" Table 14 "Dynamic characteristics", sub-section "Port timing": - changed symbol "tPV" to "tv(Q)" - changed symbol "tPS" to "tsu(D)" - changed symbol "tPH" to "th(D)"
*
Table 14 "Dynamic characteristics", sub-section "Reset" - changed symbol "tW" to "tw(rst)" - changed symbol "tREC" to "trec(rst)" - changed symbol "tRESET" to "trst"
PCA9550_3 (9397 750 13719) PCA9550_2 (9397 750 11461) PCA9550_1 (9397 750 10857)
20041001 20030502 20021213
Product data sheet Product data Product data
-
PCA9550_2
ECN 853-2396 29859 of PCA9550_1 24 Apr 2003 ECN 853-2396 29264 of 09 Dec 2002
PCA9550_4
(c) NXP B.V. 2008. All rights reserved.
Product data sheet
Rev. 04 -- 7 January 2008
24 of 26
NXP Semiconductors
PCA9550
2-bit I2C-bus LED driver with programmable blink rates
18. Legal information
18.1 Data sheet status
Document status[1][2] Objective [short] data sheet Preliminary [short] data sheet Product [short] data sheet
[1] [2] [3]
Product status[3] Development Qualification Production
Definition This document contains data from the objective specification for product development. This document contains data from the preliminary specification. This document contains the product specification.
Please consult the most recently issued document before initiating or completing a design. The term `short data sheet' is explained in section "Definitions". The product status of device(s) described in this document may have changed since this document was published and may differ in case of multiple devices. The latest product status information is available on the Internet at URL http://www.nxp.com.
18.2 Definitions
Draft -- The document is a draft version only. The content is still under internal review and subject to formal approval, which may result in modifications or additions. NXP Semiconductors does not give any representations or warranties as to the accuracy or completeness of information included herein and shall have no liability for the consequences of use of such information. Short data sheet -- A short data sheet is an extract from a full data sheet with the same product type number(s) and title. A short data sheet is intended for quick reference only and should not be relied upon to contain detailed and full information. For detailed and full information see the relevant full data sheet, which is available on request via the local NXP Semiconductors sales office. In case of any inconsistency or conflict with the short data sheet, the full data sheet shall prevail.
to result in personal injury, death or severe property or environmental damage. NXP Semiconductors accepts no liability for inclusion and/or use of NXP Semiconductors products in such equipment or applications and therefore such inclusion and/or use is at the customer's own risk. Applications -- Applications that are described herein for any of these products are for illustrative purposes only. NXP Semiconductors makes no representation or warranty that such applications will be suitable for the specified use without further testing or modification. Limiting values -- Stress above one or more limiting values (as defined in the Absolute Maximum Ratings System of IEC 60134) may cause permanent damage to the device. Limiting values are stress ratings only and operation of the device at these or any other conditions above those given in the Characteristics sections of this document is not implied. Exposure to limiting values for extended periods may affect device reliability. Terms and conditions of sale -- NXP Semiconductors products are sold subject to the general terms and conditions of commercial sale, as published at http://www.nxp.com/profile/terms, including those pertaining to warranty, intellectual property rights infringement and limitation of liability, unless explicitly otherwise agreed to in writing by NXP Semiconductors. In case of any inconsistency or conflict between information in this document and such terms and conditions, the latter will prevail. No offer to sell or license -- Nothing in this document may be interpreted or construed as an offer to sell products that is open for acceptance or the grant, conveyance or implication of any license under any copyrights, patents or other industrial or intellectual property rights.
18.3 Disclaimers
General -- Information in this document is believed to be accurate and reliable. However, NXP Semiconductors does not give any representations or warranties, expressed or implied, as to the accuracy or completeness of such information and shall have no liability for the consequences of use of such information. Right to make changes -- NXP Semiconductors reserves the right to make changes to information published in this document, including without limitation specifications and product descriptions, at any time and without notice. This document supersedes and replaces all information supplied prior to the publication hereof. Suitability for use -- NXP Semiconductors products are not designed, authorized or warranted to be suitable for use in medical, military, aircraft, space or life support equipment, nor in applications where failure or malfunction of an NXP Semiconductors product can reasonably be expected
18.4 Trademarks
Notice: All referenced brands, product names, service names and trademarks are the property of their respective owners. I2C-bus -- logo is a trademark of NXP B.V.
19. Contact information
For additional information, please visit: http://www.nxp.com For sales office addresses, send an email to: salesaddresses@nxp.com
PCA9550_4
(c) NXP B.V. 2008. All rights reserved.
Product data sheet
Rev. 04 -- 7 January 2008
25 of 26
NXP Semiconductors
PCA9550
2-bit I2C-bus LED driver with programmable blink rates
20. Contents
1 2 3 3.1 4 5 5.1 5.2 6 6.1 6.2 6.2.1 6.3 6.3.1 6.3.2 6.3.3 6.3.4 6.3.5 6.3.6 6.4 6.5 6.6 7 7.1 7.1.1 7.2 7.3 7.4 8 8.1 8.2 9 10 11 12 13 14 15 15.1 15.2 15.3 15.4 16 17 General description . . . . . . . . . . . . . . . . . . . . . . 1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Ordering information . . . . . . . . . . . . . . . . . . . . . 2 Ordering options . . . . . . . . . . . . . . . . . . . . . . . . 2 Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Pinning information . . . . . . . . . . . . . . . . . . . . . . 3 Pinning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Pin description . . . . . . . . . . . . . . . . . . . . . . . . . 3 Functional description . . . . . . . . . . . . . . . . . . . 4 Device address . . . . . . . . . . . . . . . . . . . . . . . . . 4 Control register . . . . . . . . . . . . . . . . . . . . . . . . . 4 Control register definition . . . . . . . . . . . . . . . . . 5 Register descriptions . . . . . . . . . . . . . . . . . . . . 5 INPUT - Input register. . . . . . . . . . . . . . . . . . . . 5 PSC0 - Frequency Prescaler 0 . . . . . . . . . . . . . 5 PWM0 - Pulse Width Modulation 0 . . . . . . . . . . 5 PSC1 - Frequency Prescaler 1 . . . . . . . . . . . . . 6 PWM1 - Pulse Width Modulation 1 . . . . . . . . . . 6 LS0 - LED selector . . . . . . . . . . . . . . . . . . . . . . 6 Pins used as GPIOs . . . . . . . . . . . . . . . . . . . . . 7 Power-on reset . . . . . . . . . . . . . . . . . . . . . . . . . 7 External RESET . . . . . . . . . . . . . . . . . . . . . . . . 7 Characteristics of the I2C-bus. . . . . . . . . . . . . . 8 Bit transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 START and STOP conditions . . . . . . . . . . . . . . 8 System configuration . . . . . . . . . . . . . . . . . . . . 8 Acknowledge . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Bus transactions . . . . . . . . . . . . . . . . . . . . . . . 10 Application design-in information . . . . . . . . . 11 Minimizing IDD when the I/Os are used to control LEDs . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Programming example . . . . . . . . . . . . . . . . . . 12 Limiting values. . . . . . . . . . . . . . . . . . . . . . . . . 12 Static characteristics. . . . . . . . . . . . . . . . . . . . 13 Dynamic characteristics . . . . . . . . . . . . . . . . . 15 Test information . . . . . . . . . . . . . . . . . . . . . . . . 17 Package outline . . . . . . . . . . . . . . . . . . . . . . . . 18 Handling information. . . . . . . . . . . . . . . . . . . . 21 Soldering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Introduction to soldering . . . . . . . . . . . . . . . . . 21 Wave and reflow soldering . . . . . . . . . . . . . . . 21 Wave soldering . . . . . . . . . . . . . . . . . . . . . . . . 21 Reflow soldering . . . . . . . . . . . . . . . . . . . . . . . 22 Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Revision history . . . . . . . . . . . . . . . . . . . . . . . . 24 18 18.1 18.2 18.3 18.4 19 20 Legal information . . . . . . . . . . . . . . . . . . . . . . Data sheet status . . . . . . . . . . . . . . . . . . . . . . Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . Disclaimers. . . . . . . . . . . . . . . . . . . . . . . . . . . Trademarks . . . . . . . . . . . . . . . . . . . . . . . . . . Contact information . . . . . . . . . . . . . . . . . . . . Contents. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 25 25 25 25 25 26
Please be aware that important notices concerning this document and the product(s) described herein, have been included in section `Legal information'.
(c) NXP B.V. 2008.
All rights reserved.
For more information, please visit: http://www.nxp.com For sales office addresses, please send an email to: salesaddresses@nxp.com Date of release: 7 January 2008 Document identifier: PCA9550_4

▲Up To Search▲

Price & Availability of PCA9550TK

	To Download PCA9550TK Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .