PCA9554ATS,118

I/o Expanders Overview

The PCA9554ATS,118 is an 8-bit I2C-bus and SMBus I/O expander from NXP Semiconductors. It provides General Purpose parallel Input/Output (GPIO) expansion for I2C/SMBus applications. The device operates within a supply voltage range of 2.3 V to 5.5 V and supports clock frequencies up to 400 kHz. It features an active LOW interrupt output, polarity inversion register, and noise filters on SCL/SDA inputs. The component is housed in a 20-lead SSOP package (SOT266-1) with dimensions of 6.6 mm length by 4.5 mm width. Operating temperature ranges from -40 °C to +85 °C.

I/o Expanders Feature Summary

• Provides 8 bits of GPIO expansion via I2C-bus or SMBus interface
• Features an open-drain interrupt output activated by input state changes
• Includes a polarity inversion register for flexible logic level handling
• Offers hardware-selectable I2C addresses using three address pins

I/o Expanders Applications

• ACPI power switches
• Sensor interfaces
• Push button scanning
• LED control systems
• Fan speed monitoring

I/o Expanders Procurement Notes

Verify the specific ordering suffix ',118' corresponds to the reel packing method when sourcing. Confirm the SSOP20 package variant matches the design footprint requirements. Ensure the fixed I2C address aligns with system bus topology constraints. Check RoHS compliance status against current regulatory standards before finalizing procurement orders.

I/o Expanders Selection Notes

Select this part when 8 additional digital I/O lines are required on an I2C bus. Consider the PCA9554A variant if a different fixed slave address is needed to accommodate more devices on the same bus line. Verify that the SSOP20 package size fits the available PCB area. Ensure the system controller can handle the required software changes due to enhanced features compared to legacy PCF8574 series parts.

I/o Expanders Part Context

This component belongs to the PCA9554 family of CMOS I/O expanders developed to enhance NXP's I2C portfolio. It shares pin-to-pin and address compatibility with the PCF8574 series but requires software updates due to added features like individual I/O configuration and interrupt outputs. The ATS marking indicates the specific package and address variant within the broader product line.

I/o Expanders Replacement Considerations

Texas Instruments TCA9554DWR and TCA9554PWR are listed as manufacturer-recommended replacements for discontinued SOIC variants. Verify electrical characteristics and register compatibility before substituting. Software modifications may be necessary due to differences in enhancement features between original and replacement parts.