PCA9555DBQR datasheet by Texas Instruments

PCA9555DBQR Frequently Asked Questions (FAQs)

• What is the maximum frequency of the I2C bus that the PCA9555DBQR can support?
  The PCA9555DBQR can support I2C bus frequencies up to 400 kHz.
• How do I configure the PCA9555DBQR to operate in input mode?
  To configure the PCA9555DBQR to operate in input mode, set the corresponding bit in the configuration register (register 0x06) to '1'. This will enable the input mode for the respective pin.
• What is the maximum current that the PCA9555DBQR can sink or source per pin?
  The PCA9555DBQR can sink or source up to 25 mA per pin.
• How do I reset the PCA9555DBQR?
  The PCA9555DBQR can be reset by pulling the RESET pin low for at least 1 ms. This will reset the device to its default state.
• What is the purpose of the internal pull-up resistors on the PCA9555DBQR?
  The internal pull-up resistors on the PCA9555DBQR are used to pull up the I2C bus lines (SDA and SCL) to the supply voltage (VCC) when the device is not actively driving the bus.