PCA9557PW Datasheet – 8-bit I2C-bus and SMBus I/O port

Part Number : PCA9557PW

Function : 8-bit I2C-bus and SMBus I/O port with reset

Package : SO 16, TSSOP 16, HVQFN16 Type

Manufacturers : NXP Semiconductors.

Pinouts :

PCA9557PW datasheet

Description :

The PCA9557 is a silicon CMOS circuit which provides parallel input/output expansion for
SMBus and I2C-bus applications. The PCA9557 consists of an 8-bit input port register,
8-bit output port register, and an I2C-bus/SMBus interface. It has low current consumption
and a high-impedance open-drain output pin, IO0.

The system master can enable the PCA9557’s I/O as either input or output by writing to
the configuration register. The system master can also invert the PCA9557 inputs by
writing to the active HIGH polarity inversion register. Finally, the system master can reset
the PCA9557 in the event of a time-out by asserting a LOW in the reset input.


Features :

1. Lower voltage, higher performance migration path for the PCA9556

2. 8 general purpose input/output expander/collector

3. Input/output configuration register

4. Active HIGH polarity inversion register

5. I2C-bus and SMBus interface logic

6. Internal power-on reset

7. Noise filter on SCL/SDA inputs

8. Active LOW reset input


PCA9557PW Datasheet PDF Download

PCA9557PW pdf

Other data sheets within the file : 9557, PCA9557, PCA9557BS, PCA9557D, PCA9557-PW

PCA9535 Datasheet PDF – 16-bit, Low Power I/O Port

Part Number : PCA9535

Function : 16-bit I2C-bus and SMBus, low power I/O port with interrupt

Package : SO24, TSSOP 24 Pin Type

Manufacturers : NXP Semiconductors.

Pinouts :

PCA9535 datasheet


General description

The PCA9535 and PCA9535C are 24-pin CMOS devices that provide 16 bits of General Purpose parallel Input/Output (GPIO) expansion for I2C-bus/SMBus applications and was developed to enhance the NXP Semiconductors family of I2C-bus I/O expanders. The improvements include higher drive capability, 5 V I/O tolerance, lower supply current, individual I/O configuration, and smaller packaging.

I/O expanders provide a simple solution when additional I/O is needed for ACPI power switches, sensors, push buttons, LEDs, fans, etc.The PCA9535 and PCA9535C consist of two 8-bit Configuration (Input or Output selection), Input, Output and Polarity Inversion (active HIGH or active LOW operation) registers. The system master can enable the I/Os as either inputs or outputs by writing to the I/O configuration bits. The data for each input or output is kept in the corresponding Input or Output register. The polarity of the read register can be inverted with the Polarity Inversion register. All registers can be read by the system master. Although pin-to-pin and I2C-bus address compatible with the PCF8575, software changes are required due to the enhancements and are discussed in Application Note AN469.


1. Operating power supply voltage range of 2.3 V to 5.5 V
2. 5 V tolerant I/Os
3. Polarity Inversion register
4. Active LOW interrupt output
5. Low standby current
6. Noise filter on SCL/SDA inputs
7. No glitch on power-up
8. Internal power-on reset
9. 16 I/O pins which default to 16 inputs
10. 0 Hz to 400 kHz clock frequency
11. ESD protection exceeds 2000 V HBM per JESD22-A114, 200 V MM per
12. JESD22-A115, and 1000 V CDM per JESD22-C101
13. Latch-up testing is done to JEDEC Standard JESD78 which exceeds 100 mA
14. Offered in four different packages: SO24, TSSOP24, HVQFN24 and HWQFN24

Other data sheets within the file : PCA9535BS, PCA9535C, PCA9535CD, PCA9535CHF

PCA9535 Datasheet PDF

PCA9535 pdf