CAT9555HT6I-GT2

Overview

The CAT9555HT6I-GT2 is a 16-bit I/O expander manufactured by onsemi, designed for I2C and SMBus interfaces. It features two 8-bit configuration registers (A and B) that determine the direction of each port's pins. The device includes an interrupt output pin to signal state changes on inputs. It operates within a supply voltage range of 2.3 V to 5.5 V and supports a maximum clock frequency of 400 kHz. The component is housed in a 24-pin HVQCCN package with dimensions of 4 mm length. It functions reliably across an operating temperature range from -40 °C to +85 °C.

Feature Summary

• Provides 16 general-purpose digital input/output ports accessible via standard I2C or SMBus protocols.
• Features an interrupt output mechanism to notify the host processor of input state changes without continuous polling.
• Supports flexible configuration through individual pin direction control registers for each of the two ports.

Applications

• Embedded systems requiring expanded GPIO capabilities over serial buses.
• Industrial control panels needing remote input monitoring and output switching.
• Consumer electronics utilizing I2C/SMBus communication architectures.

Procurement Notes

Verify the specific suffix HT6 against official onsemi documentation to confirm package type and tape/reel specifications. Ensure compatibility with existing PCB footprints for the HVQCCN-24 package. Confirm RoHS compliance status as indicated in current datasheets before finalizing procurement orders.

Selection Notes

Select this component when 16 bidirectional I/O lines are required with interrupt capability. Compare against similar models like CAT9555HV6I-G if higher voltage tolerance or different packaging is needed. Ensure the system bus speed does not exceed the 400 kHz limit defined in the electrical characteristics.

Part Context

This part belongs to the CAT9555 series of I/O expanders from onsemi. It shares functional similarities with other 16-bit I2C expanders but is distinguished by its specific package variant and thermal rating. It serves as a bridge between microcontrollers and peripheral devices requiring additional digital I/O resources.

Replacement Considerations

The CAT9555HV6I-G is a documented related part number within the same family. Verify pinout and register compatibility before substitution. Other equivalents may include NXP PCA9555 variants, though electrical parameters must be cross-referenced carefully.