PCF8575PWE4 datasheet by Texas Instruments

PCF8575PWE4 Frequently Asked Questions (FAQs)

• What is the maximum frequency of the I2C bus that the PCF8575PWE4 can support?
  The PCF8575PWE4 can support I2C bus frequencies up to 400 kHz, but it is recommended to operate at 100 kHz or lower for reliable operation.
• Can the PCF8575PWE4 be used as a level shifter for I2C signals?
  Yes, the PCF8575PWE4 can be used as a level shifter for I2C signals, as it can translate between 3.3V and 5V logic levels.
• How do I handle the internal pull-up resistors on the I2C bus?
  The internal pull-up resistors on the I2C bus can be disabled by connecting the PU pin to GND. If you want to use external pull-up resistors, connect the PU pin to VCC.
• What is the maximum current that can be sourced or sunk by the PCF8575PWE4?
  The PCF8575PWE4 can source or sink up to 25 mA of current per I/O pin, but it is recommended to limit the current to 10 mA or less to ensure reliable operation.
• Can the PCF8575PWE4 be used in a multi-master I2C bus configuration?
  Yes, the PCF8575PWE4 can be used in a multi-master I2C bus configuration, but it requires careful design and consideration of bus arbitration and collision detection.