PCF8574AP

The PCF8574 is designed for the I2C-bus interface.

The PCF8574 is a remote 8-bit I/O expander for the I2C-bus interface. It has latched outputs with high-current drive capability for directly driving LEDs and includes an interrupt line (INT) that can inform the microcontroller of incoming data on its ports without using the I2C-bus. This allows the PCF8574 to remain a simple slave device. The PCF8574 and PCF8574A versions differ only in their slave address. The PCF8574 provides an open drain output (INT) that can be connected to the microcontroller to initiate actions elsewhere in the system. Interrupts are generated by any rising or falling edge of the port inputs in the input mode, and resetting and reactivating the interrupt circuit is achieved by changing data on the port to the original setting or by reading from or writing to the port that generated the interrupt. Resetting occurs during the acknowledge bit in the READ mode after the rising edge of the SCL signal and in the WRITE mode after the HIGH-to-LOW transition of the SCL signal.

The PCF8574 is a remote 8-bit I/O expander for I2C-bus with low current consumption and latched outputs for driving LEDs. It includes an interrupt line (INT) that can inform the microcontroller of incoming data without using the I2C-bus. The PCF8574 can function as a simple slave device. The PCF8574 and PCF8574A versions differ only in their slave address. The PCF8574 is available in different package versions such as PDIP16, SO16, and SSOP20. The product is not designed for use in life support applications, and Philips customers using it for such purposes do so at their own risk.