The PCA9555PW can support I2C bus frequencies up to 400 kHz.
The PCA9555PW can be configured for 8-bit or 16-bit port expansion by setting the A0 and A1 address pins. For 8-bit expansion, tie A0 and A1 to GND, and for 16-bit expansion, tie A0 to VCC and A1 to GND.
The PCA9555PW can sink or source up to 25 mA per output.
The PCA9555PW can be reset by pulling the RESET pin low for at least 1 ms.
Yes, the PCA9555PW is 5V tolerant, but it is recommended to use a 3.3V power supply for optimal performance.
PCA9555PW datasheet
by Texas Instruments
