PCA9673PW,118

I/o Expanders Overview

The PCA9673PW,118 is a remote 16-bit I/O expander for Fast-mode Plus I2C-bus systems with interrupt and reset capabilities. It operates within a voltage range of 2.3 V to 5.5 V, featuring 5.5 V tolerant I/Os. The device provides latched outputs with 25 mA sink capability per pin and a total package sink capacity of 400 mA. It supports 1 MHz I2C bus speeds compliant with Fast and Standard modes, offering 30 mA SDA sink capability. Sixteen programmable slave addresses are available via two address pins. The component includes an active LOW open-drain interrupt output and readable device ID information.

I/o Expanders Feature Summary

• Provides 16-bit quasi-bidirectional I/O expansion compatible with I2C Fast-mode Plus interfaces.
• Features high current drive capabilities with 25 mA per pin and 400 mA total package sink capacity.
• Includes hardware reset input and software reset functionality via I2C General Call address.
• Generates interrupt signals on port changes without requiring continuous I2C polling.

I/o Expanders Applications

• LED signs and displays
• Servers
• Industrial control systems
• Medical equipment
• Programmable Logic Controllers (PLCs)

I/o Expanders Procurement Notes

Verify the specific ordering suffix

I/o Expanders Selection Notes

Select this component when upgrading from PCF8575 designs to utilize higher I2C bus speeds and increased drive currents. Ensure the application requires 16-bit expansion and benefits from the hardware reset pin replacing the second address pin found in legacy devices. Confirm that the TSSOP24 package fits the PCB layout constraints.

I/o Expanders Part Context

The PCA9673 serves as a drop-in upgrade for the PCF8575, offering enhanced performance through Fast-mode Plus support. It replaces the A2 address pin with a dedicated RESET input, simplifying system design while providing more available device addresses. This evolution allows for greater bus density and improved LED dimming capabilities compared to its predecessor.

I/o Expanders Replacement Considerations

The PCA9673 is documented as a direct replacement for the PCF8575. When substituting, note that the A2 address pin on the PCF8575 corresponds to the RESET input on the PCA9673. Verify that the host microcontroller can handle the different address mapping and utilizes the reset functionality appropriately.