PCA9554DW

I/o Expanders Overview

The PCA9554DW is a discontinued 8-bit I/O expander manufactured by Texas Instruments, housed in a 16-SOIC package. It supports I2C and SMBus interfaces with a maximum clock frequency of 400 kHz. The device operates on a supply voltage range of 2.3 V to 5.5 V and features push-pull outputs capable of sourcing or sinking up to 25 mA. It includes an interrupt output pin and internal power-on reset (POR) functionality. The component is rated for industrial temperatures between -40°C and +85°C.

I/o Expanders Feature Summary

• Provides 8-bit general-purpose parallel input/output expansion for I2C bus applications
• Features configurable individual I/O pins as inputs or outputs via configuration registers
• Includes open-drain interrupt output to signal input state changes to the system host

I/o Expanders Applications

• ACPI power switch control
• Sensor interface expansion
• Push button scanning
• LED driver control

I/o Expanders Procurement Notes

This component has reached end-of-life status and is no longer manufactured. Verification of availability requires checking authorized distributors for remaining stock or approved replacement parts. Ensure that any substitute components match the required electrical specifications and pinout compatibility before integration into existing designs.

I/o Expanders Selection Notes

Designers should consider the TCA9554 series as direct replacements, noting potential differences in supply voltage ranges and output drive types. The original PCA9554DW utilizes push-pull outputs, whereas some successors may offer open-drain configurations. Verify register compatibility and software adjustments are necessary when migrating to newer variants within the expanded family.

I/o Expanders Part Context

The PCA9554 series was developed to enhance previous NXP Semiconductors I2C I/O expander families by offering higher drive capability and 5 V I/O tolerance. Texas Instruments acquired this product line, continuing production until its discontinuation. The DW suffix specifically denotes the 16-pin wide SOIC package variant suitable for surface-mount assembly.

I/o Expanders Replacement Considerations

TCA9554DWR and TCA9554PWR are manufacturer-recommended substitutes. Note that these alternatives operate over a wider voltage range (1.65 V to 5.5 V) and feature open-drain outputs instead of the original's push-pull configuration. Software modifications may be required to accommodate these electrical differences.