CY8C9540A-24PVXI

Overview

The CY8C9540A-24PVXI is a 40-bit I/O expander with integrated EEPROM, operating within a 3 V to 5.25 V supply range and supporting temperatures from -40 °C to +85 °C. It features an I2C interface compatible with SMBus, allowing up to 128 devices on a single bus via extendable soft addressing. The device provides 40 independently configurable GPIO pins and eight 8-bit PWM sources. Internal memory includes 11 Kbytes of user-available EEPROM for data storage and dedicated registers for storing power-on reset defaults.

Feature Summary

• Supports independent configuration of I/O pins as inputs, outputs, quasi-bidirectional ports, or PWM outputs with selectable drive modes.
• Integrates 11 Kbytes of EEPROM for general data storage and non-volatile retention of port configuration defaults.
• Features eight independently configurable 8-bit PWM channels driven by multiple internal clock sources.
• Utilizes an extendable soft addressing algorithm that allows unused address pins to function as general-purpose I/O.

Applications

• Monitoring and controlling board-level peripherals such as LEDs and intrusion detection sensors.
• Storing manufacturing data and error codes in onboard EEPROM for diagnostic read-back.
• Expanding system I/O capabilities in embedded controllers requiring additional digital inputs and outputs.

Procurement Notes

Verify the specific ordering suffix against official Infineon documentation to confirm package type and temperature grade. Ensure the I2C master supports clock stretching, as required by this device's communication protocol. Confirm RoHS compliance status through the manufacturer's current product qualification reports before finalizing procurement specifications.

Selection Notes

Select the CY8C9540A variant when exactly 40 I/O lines and eight PWM channels are required. Consider the CY8C9520A for lower pin counts or the CY8C9560A for expanded I/O and PWM resources. Verify that the SSOP-48 package fits the available PCB footprint and that the voltage levels match the system's logic requirements.

Part Context

This component belongs to the CY8C95xxA family of I/O expanders manufactured by Infineon Technologies (formerly Cypress Semiconductor). The family shares identical architecture and command sets, differing primarily in the number of I/O pins, PWM sources, and EEPROM capacity. The CY8C9540A serves as the mid-range option within this series.

Replacement Considerations

Direct replacements within the same family include the CY8C9520A and CY8C9560A, which share pinout compatibility where applicable but differ in I/O count. Cross-family replacements require verification of register compatibility and electrical characteristics.