ATSHA204A-XHDA-T

Specialized ICS Overview

The ATSHA204A-XHDA-T is a CryptoAuthentication™ security IC manufactured by Microchip Technology, housed in an 8-lead TSSOP package. It provides hardware-based key storage and symmetric authentication using the SHA-256 algorithm. The device supports up to 16 keys with 256-bit lengths and includes a unique 72-bit serial number. It features 4.5 KB of EEPROM for data and keys, alongside 512 bits of One-Time Programmable (OTP) memory. Communication occurs via a 1 MHz I²C interface or a high-speed single-wire interface. Operating voltages range from 2.0V to 5.5V, with sleep current below 150 nA.

Specialized ICS Feature Summary

• Implements SHA-256 hashing with MAC and HMAC options for secure symmetric authentication.
• Stores up to 16 secret keys within protected hardware-based EEPROM.
• Includes an internal high-quality Random Number Generator (RNG) to prevent replay attacks.
• Features a guaranteed unique 72-bit serial number for device identification.

Specialized ICS Applications

• Secure download and boot processes
• Ecosystem control and accessory authentication
• Anti-cloning protection for hardware components
• Message security and session key exchange

Specialized ICS Procurement Notes

Verify the ordering suffix 'XHDA' corresponds to the 8-TSSOP package and Tape & Reel packaging format as specified in the product parameters. Confirm that the specific revision level matches the design requirements, as datasheet revisions may impact command set details or electrical characteristics. Ensure compatibility with the host system's I²C voltage levels before integration.

Specialized ICS Selection Notes

Select this component when hardware-level authentication is required without complex asymmetric cryptography. It is suitable for applications needing secure key storage and challenge-response protocols. Consider the 8-TSSOP package if surface-mount space allows. For systems requiring fewer GPIO pins, evaluate the single-wire interface option available on other package variants within the same family.

Specialized ICS Part Context

This part belongs to the ATSHA204A series within the Microchip CryptoAuthentication™ family. It serves as a cost-effective solution for securing embedded systems against cloning and unauthorized access. The device complements standard microcontrollers by offloading cryptographic operations and securely storing sensitive data that cannot be extracted via software debugging.

Specialized ICS Replacement Considerations

The ATSHA204A is compatible with the original ATSHA204. Verify pinout and command set equivalence when substituting. Other packages such as SOIC, UDFN, or SOT23 offer the same functionality but differ in physical dimensions and interface configurations.