HCS370/P

Specialized ICS Overview

The HCS370/P is a KEELOQ code hopping encoder manufactured by Microchip Technology, housed in a 14-pin PDIP package. It operates on a supply voltage of 2.05V to 5.5V and features six button inputs supporting up to 15 distinct functions. The device utilizes nonlinear encryption algorithms to generate unique 67-bit or 69-bit transmission codes, incorporating a 32-bit hopping code and serial number data. Internal EEPROM stores two programmable 64-bit keys, two 32-bit serial numbers, and synchronization counters. It supports multiple modulation formats including PWM, VPWM, PPM, and Manchester.

Specialized ICS Feature Summary

• KEELOQ Code Hopping Security: Generates unique 67/69-bit transmissions using a 32-bit hopping code and read-protected 64-bit crypt keys.
• Dual Encoder Capability: Supports two independent transmitter configurations selectable via the SHIFT pin.
• Integrated Power Management: Includes an onboard step-up voltage regulator and low-voltage battery detection with status reporting.
• Flexible Modulation Support: Configurable for PWM, VPWM, PPM, and Manchester modulation with selectable baud rates.

Specialized ICS Applications

• Automotive Remote Keyless Entry (RKE) systems
• Automotive alarm and immobilizer systems
• Gate and garage door openers
• Identity tokens and access control systems

Specialized ICS Procurement Notes

Verify the specific suffix '/P' corresponds to the 14-pin DIP package variant during sourcing. Confirm that the component has been programmed with the required manufacturer keys and serial numbers, as the internal EEPROM is read-protected after production. Ensure compatibility with the intended decoder's learning mode and modulation settings.

Specialized ICS Selection Notes

Select this model for applications requiring secure unidirectional authentication with minimal external components. The PDIP package is suitable for through-hole assembly. Consider the dual encoder feature if two distinct transmitter profiles are needed from a single chip. Verify that the operating voltage range of 2.05V to 5.5V aligns with the system power design.

Specialized ICS Part Context

The HCS370 belongs to the KEELOQ family of logic ICs designed for high-security remote control applications. It replaces older fixed-code encoders by implementing rolling code technology to prevent code grabbing and scanning attacks. The '/P' designation specifically identifies the plastic dual in-line package version within the broader HCS370 product line.

Specialized ICS Replacement Considerations

Publicly confirmed substitute part numbers are not available in the provided documentation. When replacing legacy fixed-code encoders, ensure the new decoder supports KEELOQ learning protocols and compatible modulation formats such as PWM or VPWM.

Specialized ICS FAQ

How does the HCS370 prevent code grabbing attacks?

It uses KEELOQ code hopping technology where each transmission includes a 32-bit encrypted hopping code derived from a synchronization counter. This ensures every transmitted code is unique and unpredictable.

What security parameters are stored in the HCS370?

The device contains nonvolatile EEPROM storing two 64-bit encoder keys, two 32-bit serial numbers, two 60-bit seed values, and synchronization counters. These values are read-protected against external access.

Can the HCS370 support two different transmitters?

Yes, it features dual encoder functionality. The SHIFT input pin allows selection between Encoder 1 and Encoder 2, each with its own set of keys, serial numbers, and configuration options.