Analog Devices Inc./Maxim Integrated DS28E02P+

Overview

DS28E02P+ from Maxim Integrated is a 1-Wire SHA-1 authenticated 1Kb EEPROM IC with integrated 512-bit cryptographic engine, 64-bit factory-programmed ROM ID, and four 256-bit write-protected memory pages. It operates from 1.75V to 3.65V across –20°C to +85°C and supports 12.5kbps/35.7kbps 1-Wire communication for secure accessory authentication in medical consumables and printer cartridges.

For engineers reviewing the DS28E02P+ datasheet, DS28E02P+ pinout, DS28E02P+ application, or DS28E02P+ equivalent, key selection criteria include guaranteed unique 64-bit ROM ID, on-chip SHA-1 MAC generation, EPROM-emulation mode for Page 1, 200,000 write/erase cycles, and TSOC-6 package compatibility with parasitic power operation.

Technical Context

The DS28E02P+ implements a dedicated 512-bit SHA-1 engine that computes 160-bit message authentication codes (MACs) using a user-programmable 64-bit secret and device-specific data including the 64-bit ROM ID. All memory writes require prior MAC authorization, enforcing cryptographic access control.

Its 1024-bit EEPROM is partitioned into four 256-bit pages with per-page write protection and OTP-style "write-to-0" emulation for Page 1. Communication follows the 1-Wire protocol with open-drain IO, switchpoint hysteresis (0.26V–1.02V), and dual-speed timing (standard/overdrive), enabling robust noise-immune operation on single-wire buses.

Key Specifications

Pinout & Package

DS28E02P+ uses a 6-pin TSOC (Thin Small Outline Package) with exposed pad not present. Pin 1 is GND, Pin 2 is IO (open-drain 1-Wire bus interface), and Pins 3–6 are no-connect (N.C.). External pullup resistor (≤750Ω) required on IO for proper 1-Wire signaling.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar authenticated EEPROM applications.

Compared with DS28E02P+, DS28E15P+ provides stronger cryptographic assurance and double memory but requires firmware updates for SHA-256 command handling, while DS2432P+ offers simpler CRC validation at the expense of cryptographic robustness and secret management.

Availability

DS28E02P+ is available at Aetrix Electronics and suitable for medical consumable authentication, printer cartridge configuration, and sensor calibration applications requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for DS28E02P+ includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Maxim Integrated (now part of Analog Devices) is a semiconductor company specializing in analog, mixed-signal, and secure ICs for industrial, medical, and communications systems.

The DS28E02P+ belongs to Maxim's 1-Wire secure authentication product line, designed specifically for hardware-enforced IP protection, consumable anti-counterfeiting, and trusted peripheral identification in resource-constrained embedded systems.

FAQ

What is the primary security function of the DS28E02P+?

The DS28E02P+ provides FIPS 180-3 SHA-1–based challenge-response authentication using a user-programmable 64-bit secret and its factory-guaranteed 64-bit ROM ID. Every write operation requires a valid 160-bit MAC computed by the on-chip SHA-1 engine - preventing unauthorized memory modification without knowledge of the secret. This makes DS28E02P+ suitable for high-assurance applications like medical consumable authentication.

Does the DS28E02P+ require an external power supply (VCC)?

No, the DS28E02P+ operates in parasitic power mode using only the 1-Wire bus (IO) and GND pins - it harvests energy during strong pull-up phases to power internal circuitry, including the SHA-1 engine and EEPROM programming. This eliminates the need for a dedicated VCC connection, simplifying PCB layout and reducing bill-of-materials cost in space-constrained designs utilizing DS28E02P+.

How is memory protection implemented in the DS28E02P+?

DS28E02P+ supports user-programmable write protection for Page 0, Page 3, or all four 256-bit pages. Additionally, Page 1 can be placed in EPROM-emulation mode, allowing bits to change only from 1 to 0 - enabling irreversible configuration flags or license keys. Protection settings are stored in nonvolatile registers and enforced at the hardware level, independent of host software control.

What package type does the DS28E02P+ use, and is it RoHS-compliant?

The DS28E02P+ uses a 6-pin TSOC (Thin Small Outline Package) with lead (Pb)-free and RoHS-compliant construction, as indicated by the "+" suffix in the part number. Its footprint matches industry-standard TSOC-6 layouts, and all pins except IO and GND are no-connect - simplifying layout and ensuring compatibility with existing 1-Wire system designs using DS28E02P+.

Can the DS28E02P+ operate across different 1-Wire communication speeds?

Yes, the DS28E02P+ supports both standard-speed (12.5kbps max) and overdrive-speed (35.7kbps max) 1-Wire communication, selected via ROM function commands (e.g., Overdrive-Skip ROM). Switchpoint hysteresis (0.26V–1.02V) and input filtering ensure reliable operation at either speed in electrically noisy environments - a key design feature confirmed in DS28E02P+ characterization across –20°C to +85°C.