PCF8574TS/3,118

I/o Expanders Overview

The PCF8574TS/3,118 is an 8-bit remote I/O expander for the two-wire bidirectional I2C-bus (SCL, SDA). It provides general-purpose remote I/O expansion via eight quasi-bidirectional ports operating between 2.5 V and 6 V. The device features a 100 kHz I2C interface, three hardware address inputs, and an active LOW open-drain interrupt output. It includes latched outputs with high-current drive capability for directly driving LEDs and has a total package sink capability of 80 mA. The SSOP20 package version offers low standby current consumption of 2.5 µA typical.

I/o Expanders Feature Summary

• I2C-bus to parallel port expander
• Active LOW open-drain interrupt output
• Eight programmable slave addresses using three address pins
• Latch-up testing exceeds 100 mA per JEDEC standard JESD78

I/o Expanders Applications

• LED signs and displays
• Servers
• Key pads
• Industrial control
• Medical equipment

I/o Expanders Procurement Notes

Verify the specific orderable part number suffix against the manufacturer's official ordering information table to confirm the exact packaging method and reel specifications. Ensure the selected variant matches the required temperature range and marking standards for the intended production environment.

I/o Expanders Selection Notes

Select this component when a microcontroller requires additional digital input or output lines without consuming internal GPIO resources. The device is suitable for applications needing simple I2C communication with minimal software overhead due to its single-register architecture and lack of direction control signals.

I/o Expanders Part Context

This component belongs to the PCF8574 family of remote I/O expanders designed for I2C bus systems. It serves as a cost-effective solution for expanding processor capabilities in embedded designs where pin counts are limited but additional peripheral control is necessary.

I/o Expanders Replacement Considerations

PCA9674/74A offers higher speed and drive capability. PCA8574/74A supports 400 kHz operation. PCA9670 and PCA9672 provide hardware reset options.