PCF8574ADWE4 datasheet by Texas Instruments

PCF8574ADWE4 Frequently Asked Questions (FAQs)

• What is the maximum frequency of the I2C bus that the PCF8574ADWE4 can support?
  The PCF8574ADWE4 can support I2C bus frequencies up to 400 kHz.
• Can the PCF8574ADWE4 be used as a input expander?
  Yes, the PCF8574ADWE4 can be used as an input expander. It has internal pull-up resistors on the I/O pins, which can be used to connect switches or other input devices.
• How do I reset the PCF8574ADWE4?
  The PCF8574ADWE4 can be reset by pulling the SCL pin low for at least 10 ms. This will reset the device and clear all registers.
• What is the maximum current that can be sourced or sunk by the I/O pins?
  The I/O pins of the PCF8574ADWE4 can source or sink up to 25 mA of current.
• Can the PCF8574ADWE4 be used with 5V microcontrollers?
  Yes, the PCF8574ADWE4 is 5V tolerant, meaning it can be used with 5V microcontrollers. However, the VCC pin should be connected to a 3.3V power supply.