PCA9555D,112

I/o Expanders Overview

The PCA9555D,112 is a 24-pin CMOS device providing 16-bit General Purpose parallel Input/Output (GPIO) expansion for I²C-bus and SMBus applications. It operates within a supply voltage range of 2.3 V to 5.5 V and supports clock frequencies up to 400 kHz. The component features 5 V tolerant I/Os, an active LOW interrupt output, and low standby current. It includes noise filters on SCL/SDA inputs, internal power-on reset, and ESD protection exceeding 2000 V HBM. Packaged in SO-24, it allows up to eight devices to share the same bus via hardware address pins A0, A1, and A2.

I/o Expanders Feature Summary

• Provides 16-bit GPIO expansion with individual input/output configuration capabilities
• Features an open-drain interrupt output activated by input state changes
• Includes polarity inversion registers for flexible logic level handling
• Supports multiple devices on a single bus through three hardware address pins

I/o Expanders Applications

• ACPI power switches
• Sensor interface modules
• Push button arrays
• LED driver circuits
• Fan control systems

I/o Expanders Procurement Notes

Verify the ordering suffix '112' corresponds to the tube packaging format specified in the datasheet. Confirm the manufacturer designation matches NXP Semiconductors documentation. Ensure the part number aligns with the SO-24 package variant. Cross-reference the RoHS compliance status using official product data sheets before finalizing procurement orders.

I/o Expanders Selection Notes

Select this component when pin-to-pin compatibility with PCF8575 is required but enhanced drive capability or lower supply current is needed. Verify that the system master can accommodate necessary software changes due to register enhancements. Ensure the application environment stays within the -40 °C to +85 °C operating temperature range and utilizes standard I²C/SMBus communication protocols.

I/o Expanders Part Context

This part belongs to the PCA9555 series developed to enhance the NXP Semiconductors family of I²C-bus I/O expanders. It shares the fixed I²C-bus address with the PCA9554, allowing mixed combinations on the same bus. The device improves upon previous generations by offering smaller packaging options and independent I/O configuration, distinguishing it from basic parallel expanders.

I/o Expanders Replacement Considerations

The PCA9555 is pin-to-pin compatible with the PCF8575; however, software modifications are required due to functional enhancements. Direct substitutes include other variants within the PCA9555 family such as PCA9555DB or PCA9555PW, provided the package type meets the design constraints.