PCF8574TS/3,112

I/o Expanders Overview

The PCF8574TS/3,112 is an 8-bit remote I/O expander for the two-wire bidirectional I²C-bus (SCL, SDA). It features eight quasi-bidirectional ports, three hardware address inputs, and an active LOW open-drain interrupt output. Operating between 2.5 V and 6 V, it provides a low standby current of 2.5 µA typical. The device supports Standard-mode I²C at 100 kHz and allows up to eight devices on the same bus via address pins A0–A2. Latched outputs directly drive LEDs with a total package sink capability of 80 mA. It operates from -40 °C to +85 °C.

I/o Expanders Feature Summary

• Quasi-bidirectional I/O ports without direction control registers
• Active LOW open-drain interrupt output for state change notification
• Latch-up performance exceeding 100 mA per JEDEC standard JESD78
• Power-on reset initializes I/Os as inputs with weak internal pull-ups

I/o Expanders Applications

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

I/o Expanders Procurement Notes

Verify the specific ordering suffix ',112' against the manufacturer's official documentation to confirm the SSOP20 tube packing method and DSC bulk pack configuration. Ensure the fixed slave address portion corresponds to the PCF8574 variant rather than the PCF8574A variant, as these share identical functionality but differ in address mapping.

I/o Expanders Selection Notes

Select this component when a microcontroller requires additional digital I/O lines via a simple I²C interface. It is suitable for applications needing direct LED driving or keypad monitoring where high-speed communication is not critical. Consider the SSOP20 package constraints and ensure external pull-up resistors are provided for the I²C bus lines if necessary.

I/o Expanders Part Context

This part belongs to the PCF8574 family of remote I/O expanders. It shares functional similarities with the PCF8574T/3 but utilizes a different package type. The 'TS' designation indicates the SSOP20 plastic shrink small outline package. It serves as a drop-in replacement for other 8-bit I/O expanders in designs requiring expanded GPIO capabilities over the I²C bus.

I/o Expanders Replacement Considerations

The PCA9674 offers higher speed (1 MHz Fm+) and greater addressability (up to 64 addresses) with similar interrupt functionality. For migration paths involving hardware reset inputs instead of interrupts, consider the PCA9670 or PCA9672 variants.