PCA9557D,118 datasheet by NXP Semiconductors

PCA9557D,118 Frequently Asked Questions (FAQs)

• What is the maximum frequency of the I2C bus that PCA9557D,118 can support?
  The PCA9557D,118 can support I2C bus frequencies up to 400 kHz.
• How do I configure the PCA9557D,118 for 8-bit or 16-bit port expansion?
  The PCA9557D,118 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.
• What is the maximum current that the PCA9557D,118 can sink or source per output pin?
  The PCA9557D,118 can sink or source up to 25 mA per output pin.
• How do I reset the PCA9557D,118?
  The PCA9557D,118 can be reset by pulling the RESET pin low for at least 1 ms.
• What is the power-on default state of the PCA9557D,118 output pins?
  The PCA9557D,118 output pins are in a high-impedance state (tri-stated) after power-on, and they remain in this state until they are configured by the I2C bus.