Part Number : PCA9557PW
Function : 8-bit I2C-bus and SMBus I/O port with reset
Package : SO, TSSOP 16, QFN 16 Pin Type
Maker : NXP Semiconductors.
Pinouts : 
Description :
The PCA9557, PCA9557PW 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
Datasheet PDF Download : 
Others datasheet of same file :
9557, PCA9557, PCA9557BS, PCA9557D, PCA9557
