PCF8575TS/1,118

I/o Expanders Overview

The PCF8575TS/1,118 is a silicon CMOS remote 16-bit I/O expander for the I2C-bus. It provides general-purpose remote I/O expansion via two bidirectional lines (SDA and SCL). The device features a 16-bit quasi-bidirectional port with latched outputs capable of directly driving LEDs. Operating supply voltage ranges from 2.5 V to 5.5 V, with a maximum standby current consumption of 10 μA. It supports FAST I2C-bus speeds up to 400 kbits/s. Addressing is configured by three hardware pins (A0, A1, A2), allowing up to eight devices on the bus. An open-drain interrupt output (INT) notifies the microcontroller of incoming data without continuous polling.

I/o Expanders Feature Summary

• Provides 16-bit remote I/O expansion using a standard two-line I2C interface.
• Features an open-drain interrupt output to signal input state changes to the host controller.
• Includes latched outputs with high current drive capability suitable for direct LED connection.
• Supports multiple device addressing through three dedicated hardware address pins.

I/o Expanders Applications

• Remote I/O expansion for microcontroller systems requiring additional digital inputs or outputs.
• Driving LED arrays utilizing the high current drive capability of the latched outputs.
• Monitoring external switch states or sensor signals via the quasi-bidirectional ports.
• Integrating into industrial control systems where low standby power consumption is required.

I/o Expanders Procurement Notes

Verify that the component matches the SSOP24 package outline specified in the datasheet. Confirm the operating temperature range meets application requirements of -40 °C to +85 °C. Ensure the I2C bus pull-up resistors are correctly sized for the 400 pF capacitive load limit. Check for physical damage to the leads before soldering, as improper handling may affect reliability.

I/o Expanders Selection Notes

Select this component when a system requires more than 8 bits of I/O expansion but does not need SPI interface speed. It is suitable for applications where the I2C bus is already available and multiple expanders must coexist on the same bus. Consider the 2.5 V to 5.5 V supply range compatibility with the target microcontroller logic levels. Evaluate the 10 μA standby current against battery-powered design constraints.

I/o Expanders Part Context

The PCF8575 series serves as a remote I/O expander within the NXP I2C-bus family. It replaces older discrete logic solutions for expanding GPIO counts. The TS suffix indicates the SSOP24 plastic shrink small outline package variant. This part is designed to interface directly with most microcontroller families supporting the I2C protocol.

I/o Expanders Replacement Considerations

The PCA9673 is documented as a direct upgrade alternative offering higher bus speeds and drive capabilities. Verify pinout compatibility and register mapping differences before substitution. Ensure the replacement supports the required interrupt functionality and voltage levels.