Analog Devices Inc./Maxim Integrated DS28E25P+T

The DS28E25 uses an on-chip SHA-256 engine to compute message authentication codes from a protected secret, host challenge, user-memory data, and its factory-programmed 64-bit ROM ID. Slave-to-host authentication validates an attached device; host-to-slave authentication can protect user EEPROM against an unauthenticated host. It communicates over a single-contact 1-Wire bus.

LCDChip registers 6-SMD, J-Lead. Analog Devices' ordering table identifies DS28E25P+T as a six-pin TSOC in tape and reel, package code D6+1. The six-pin TDFN-EP Q+T variant has a different footprint and pin assignment.

Layout checks

• Verify the controlled TSOC outline and pin-one mark.
• Provide the specified 1-Wire pullup and recovery timing.
• Confirm the bus capacitance budget with every attached node.

The expected local JPG is absent and its production URL returns HTTP 404; keep this draft unpublished until the correct asset is restored and inspected.

For the six-pin TSOC, pin 1 is GND, pin 2 is the open-drain 1-Wire IO requiring an external pullup, and pins 3 through 6 are not connected. Do not use the Q+T TDFN-EP pinout for this P+T part.

System pullup values and timing must be selected from the manufacturer electrical tables for actual network loading.

Other authenticators may differ in cryptographic algorithm, secret provisioning, EEPROM map, irreversible protections, 1-Wire commands, and footprint. Do not assume interchangeability solely from the 1-Wire interface or six-pin outline. No unverified internal alternative is linked.

Analog Devices' DS28E25 DeepCover Secure Authenticator with 1-Wire SHA-256 and 4Kb User EEPROM, abridged data sheet Rev. 4, supplies the public feature list, electrical limits, TSOC pin description, and ordering table. Request the controlled full data sheet for detailed commands.

Verify marking, traceability, TSOC dimensions and ROM ID. Test challenge generation, MAC validation, host-to-device authorization and every irreversible protection setting. Protect the secret during provisioning and confirm failure handling on the actual bus.

Confirm production documentation, TSOC land pattern, 1-Wire electrical timing, irreversible memory controls, and secret-management processes before use. Restore and inspect the production package JPG before formal publication.