CAT9554AYI-G

Overview

The CAT9554AYI-G is an 8-bit I/O expander manufactured by ON Semiconductor, formerly Catalyst Semiconductor. It interfaces with microcontrollers via the I2C and SMBus protocols, supporting clock frequencies up to 400 kHz. The device operates within a supply voltage range of 2.3 V to 5.5 V and features push-pull outputs capable of sourcing or sinking 10 mA or 24 mA. It includes an interrupt output pin and power-on reset (POR) functionality. The component is housed in a 16-TSSOP package with a width of 4.40 mm and functions across a temperature range of -40°C to +85°C.

Feature Summary

• Supports I2C and SMBus communication protocols for system integration
• Provides eight general-purpose digital input/output pins
• Includes dedicated interrupt output capability for event signaling

Applications

• Embedded systems requiring additional GPIO ports
• Consumer electronics utilizing I2C/SMBus buses
• Industrial control interfaces needing voltage level translation

Procurement Notes

Verify current availability status as this part number may be discontinued or subject to limited supply conditions. Confirm that the specific suffix corresponds to the TSSOP-16 package variant. Ensure compatibility with existing PCB footprints and verify RoHS compliance documentation before finalizing procurement decisions for production runs.

Selection Notes

Select this component when an 8-bit parallel interface expansion is required over an I2C bus. Consider the 2.3 V to 5.5 V operating range for broad voltage compatibility. Evaluate the push-pull output drive strength against load requirements. Compare against alternatives like the PCA9554 if open-drain outputs are preferred for wired-OR configurations.

Part Context

This device belongs to the CAT9554 family of I/O expanders. It serves as a bridge between microcontrollers and peripheral devices, effectively increasing the number of available control lines without consuming additional processor pins. The 'A' suffix typically denotes specific manufacturing revisions or package variations within the broader product line.

Replacement Considerations

The PCA9554APW from NXP Semiconductors is a functional alternative offering similar I2C/SMBus capabilities. Note that the PCA9554 utilizes open-drain outputs, whereas the CAT9554 provides push-pull outputs. Verify logic level compatibility and interrupt handling differences during substitution.