PCA9674PW/S911,118

I/o Expanders Overview

The PCA9674PW/S911,118 is an NXP Semiconductors remote I/O expander in a TSSOP16 package. It provides eight quasi-bidirectional ports accessible via a Fast-mode Plus (Fm+) I2C bus interface operating at 1 MHz. The device supports an operating supply voltage range of 2.3 V to 5.5 V with 5.5 V tolerant I/Os. It features latched outputs with a 25 mA sink capability per pin and a total package sink capability of 200 mA. The component includes an active LOW open-drain interrupt output and utilizes three hardware address inputs to decode up to 64 programmable slave addresses.

I/o Expanders Feature Summary

• Fast-mode Plus I2C interface supporting 1 MHz clock speeds for high-speed data transfer
• Quasi-bidirectional I/O ports that default to inputs at power-up
• Active LOW open-drain interrupt output for efficient microcontroller notification
• Readable device ID containing manufacturer, part identification, and revision information

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 matches the required packaging configuration. Confirm the device type corresponds to the intended address map, as variants exist with non-overlapping ranges. Ensure the package style aligns with the PCB footprint requirements before finalizing procurement orders.

I/o Expanders Selection Notes

Select this component when expanding I/O capacity over an I2C bus without requiring bus buffers. Consider the 1 MHz Fm+ speed for applications needing rapid LED dimming or frequent status polling. Evaluate the 25 mA per-pin sink current against load requirements to determine if external buffering is necessary for higher current demands.

I/o Expanders Part Context

This device belongs to the PCA9674 family of remote I/O expanders designed for general-purpose expansion. It serves as a functional upgrade to legacy PCF8574 devices by offering increased bus drive capabilities and higher operating frequencies. The family supports extensive addressing schemes to minimize address conflicts on shared buses.

I/o Expanders Replacement Considerations

The PCA9674A is functionally identical but uses a non-overlapping address range. Legacy PCF8574 devices are compatible upgrades but operate at lower speeds (400 kHz) and provide reduced drive currents.