PCA9554PWG4

I/o Expanders Overview

The PCA9554PWG4 is an 8-bit I/O expander from the Texas Instruments PCA9554A series, designed for I2C 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 device features eight general-purpose parallel input/output pins with configurable polarity inversion registers and interrupt output capabilities. Packaged in a 16-pin TSSOP format, it includes internal power-on reset logic and noise filters on SCL/SDA inputs. The component functions as a GPIO expander to extend system connectivity for peripherals such as sensors, buttons, and LEDs.

I/o Expanders Feature Summary

• Configurable I/O direction control via dedicated configuration registers allowing flexible input or output assignment.
• Interrupt output mechanism that activates when input states differ from their corresponding port registers.
• Hardware address selection through three pins enabling multiple devices to share the same bus without conflict.

I/o Expanders Applications

• Extending I/O capacity for ACPI power switch implementations
• Connecting sensor arrays requiring additional digital interfaces
• Managing peripheral devices like buttons and LED indicators

I/o Expanders Procurement Notes

Verify the specific suffix G4 indicates lead-free compliance and RoHS status before procurement. Confirm the package type matches the required footprint. Check current lifecycle status as older revisions may be discontinued. Ensure the supplier provides valid traceability documentation for quality assurance purposes.

I/o Expanders Selection Notes

Select this component when an 8-bit expansion is needed for I2C systems operating between 2.3 V and 5.5 V. Consider the TSSOP-16 package for surface mount assembly constraints. Verify compatibility with existing software drivers if migrating from PCF8574 series due to functional enhancements. Evaluate interrupt line availability for efficient state monitoring.

I/o Expanders Part Context

This part belongs to the PCA9554A family, which enhances the original PCA9554 with improved drive capability and lower power consumption. It maintains pin-to-pin compatibility with legacy PCF8574 devices but requires software adjustments to utilize advanced features like polarity inversion and interrupt functionality effectively.

I/o Expanders Replacement Considerations

TCA9554DWR and TCA9554PWR are confirmed manufacturer-recommended replacements for the discontinued PCA9554DW variant.