Analog Devices Inc./Maxim Integrated DS28E25G+U

The DS28E25 family supports bidirectional challenge-and-response authentication based on SHA-256. A host can authenticate an attached device, while host-to-device authentication can protect changes to user memory. The device combines a unique factory-programmed 64-bit ROM ID, protected secret storage, and 4096 bits of user EEPROM. The exact DS28E25G+U model is listed by Analog Devices with a two-contact SFN package.

The LCDChip product record and package registry designate 2-SFN. The manufacturer's exact-model page lists DS28E25G+U as SFN, and its data sheet identifies the SFN body as approximately 6 mm × 6 mm × 0.9 mm. Design for an electromechanical contact interface, not solder reflow.

Layout checks

• Match the bottom-view IO and GND contacts to the host connector.
• Confirm contact force, alignment, and polarity in the final mechanical assembly.
• Use the controlled SFN outline and attachment guidance; do not create a solder land pattern for this variant.

The package JPG is registered but currently missing locally and returns HTTP 404 on the production site. The expected path remains in this draft for later asset completion; this page must not be published until the image is restored and verified.

The manufacturer's SFN pin table assigns both contacts as follows:

The SFN drawing is a bottom view. Verify orientation on the physical holder before wiring.

Typical figures are not guaranteed limits. Review the manufacturer's revision 4 data sheet and full controlled documentation for timing, security provisioning, and all operating conditions.

Other DS28E25 ordering variants use different packages, including TO-92, TSOC, and TDFN-EP. They are not mechanical drop-in replacements for this SFN contact package. Even another SFN ordering suffix requires confirmation of supply format and exact part identity. For a different secure authenticator, validate the 1-Wire command set, SHA-256 secret provisioning, memory map, protection modes, temperature rating, package contacts, and host authentication workflow before substitution. No unverified internal replacement link is asserted here.

DS28E25G+U belongs to the Maxim Integrated DeepCover secure-authenticator family, now documented by Analog Devices. The manufacturer product page lists the exact DS28E25G+U model and SFN drawing. Technical and pin information here is based on the DS28E25 revision 4 abridged data sheet; a full data sheet is available from the manufacturer on request.

Confirm the exact full ordering code, traceability, physical SFN dimensions, and contact condition when sourcing. The unique ROM ID and cryptographic authentication are application features, not a substitute for incoming inspection or controlled secret provisioning. Do not infer the authenticity of inventory from this draft description alone.

Use the manufacturer's current controlled data sheet, SFN outline, and contact-attachment guidance for final design decisions. Confirm pullup sizing, power delivery during EEPROM programming and SHA computation, temperature limits, security provisioning, and host software behavior in the complete system. The SFN package is not qualified for soldering. This description is a technical selection aid, not a replacement for qualification testing.