PCA9555PWR datasheet by Texas Instruments

PCA9555PWR Frequently Asked Questions (FAQs)

• What is the maximum current that can be sourced or sunk by each I/O pin?
  The maximum current that can be sourced or sunk by each I/O pin is 25mA.
• How do I configure the PCA9555PWR as an input or output?
  The PCA9555PWR can be configured as an input or output by writing to the configuration register (register 0x06). A '1' in the configuration register sets the corresponding pin as an input, while a '0' sets it as an output.
• What is the purpose of the internal pull-up resistors on the I/O pins?
  The internal pull-up resistors on the I/O pins are used to pull the pins high when they are configured as inputs. This helps to prevent the pins from floating and reduces power consumption.
• How do I reset the PCA9555PWR?
  The PCA9555PWR can be reset by pulling the RESET pin low for at least 1ms. This resets all registers to their default values.
• What is the maximum frequency of the I2C clock signal?
  The maximum frequency of the I2C clock signal is 400 kHz.