HCS500T-I/SM

Specialized ICS Overview

The HCS500T-I/SM is a KEELOQ code hopping decoder designed for secure Remote Keyless Entry (RKE) systems. It operates within a supply voltage range of 3.0V to 5.5V and features an internal oscillator with automatic bit-rate detection. The device supports up to seven learned transmitters, storing encrypted manufacturer codes and crypt keys in external EEPROM via a synchronous serial interface. It includes 1 Kbit of user-accessible EEPROM and employs sophisticated error checking algorithms to validate received codes.

Specialized ICS Feature Summary

• Implements KEELOQ code hopping technology with encrypted storage of manufacturer codes and crypt keys
• Supports learning up to seven transmitters using normal or secure learning mechanisms
• Features auto bit-rate detection and internal oscillator for flexible RF reception
• Includes 1 Kbit user EEPROM and communicates via synchronous serial interface

Specialized ICS Applications

• Automotive remote entry systems
• Automotive alarm systems
• Gate and garage openers
• Electronic door locks
• Identity tokens

Specialized ICS Procurement Notes

Verify the specific suffix 'T-I/SM' corresponds to the Tape & Reel packaging variant of the HCS500 series. Confirm that the industrial temperature grade (-40°C to +85°C) matches the application requirements. Ensure the external EEPROM component selected is compatible with the TTL-level I2C interface signals provided by the decoder's EE_CLK and EE_DAT pins.

Specialized ICS Selection Notes

Select this component for unidirectional remote access control systems requiring high-security encryption. It is suitable for integration with microcontrollers via the synchronous serial interface or for stand-alone operation driving relay circuits. Ensure the system design accommodates the requirement for external EEPROM to store the manufacturer's code and transmitter synchronization data.

Specialized ICS Part Context

This part belongs to the Microchip HCS (High-Security Crypto) family, specifically utilizing the patented KEELOQ algorithm. It is designed to work in conjunction with HCS encoders that support PWM modulation formats and specific code word lengths. The T/I/SM designation indicates the surface-mount SOIJ package configuration with industrial temperature rating.

Specialized ICS Replacement Considerations

Direct replacements must support the KEELOQ protocol and similar pinout configurations. Verify compatibility with existing encoder settings, including the 28-bit serial number and 16-bit synchronization counter structure. Cross-reference with other HCS5xx series decoders if package or voltage requirements differ.