The PCA9539DB can support I2C bus frequencies up to 400 kHz.
The PCA9539DB 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 PCA9539DB can sink or source up to 25 mA per output.
The PCA9539DB can be reset by pulling the RESET pin low for at least 1 ms.
The PCA9539DB outputs are in a high-impedance state after power-on, and the internal pull-up resistors are disabled.
PCA9539DB datasheet
by Texas Instruments
