Analog Devices Inc./Maxim Integrated DS28E80Q+T

Overview

DS28E80Q+T from Maxim Integrated is a gamma-radiation-resistant, user-programmable 1-Wire nonvolatile memory IC with 248 bytes of 8-times programmable user memory organized in 31 × 8-byte blocks, factory-programmed unique 64-bit ROM ID (family code 4Ah), and open-drain IO interface. It operates from 3.3V ±10% across –40°C to +85°C and is designed for medical consumable identification and calibration data storage prior to gamma sterilization.

For engineers reviewing the DS28E80Q+T datasheet, DS28E80Q+T pinout, DS28E80Q+T application, or DS28E80Q+T equivalent, key selection considerations include its 75 kGy gamma radiation tolerance, per-block write protection, 8-cycle block endurance, 1-Wire overdrive speed support (76 kbps), and TDFN-EP 6-pin package with exposed pad.

Technical Context

The DS28E80Q+T implements a single-contact 1-Wire slave interface with open-drain IO requiring external pullup, supporting both standard (15.3 kbps) and overdrive (76 kbps) speeds. Its memory architecture includes 248-byte user memory, 32-byte administration memory, 4-byte protection memory, 8-byte SRAM write buffer, and immutable 64-bit ROM ID used as network address.

Communication relies on CRC-16 error detection at multiple protocol layers - including command/parameter, block data, and protection status - with mandatory release byte (00h–FFh) to initiate self-timed programming. Block-level write protection is irreversible and verified via Read Block Protection (AAh) and Read Remaining Cycles (A5h) commands.

Key Specifications

Pinout & Package

DS28E80Q+T uses a 6-pin TDFN-EP (3 mm × 3 mm) package with exposed thermal pad soldered to PCB ground plane. Pins 1, 4–6 are not connected; Pin 2 is open-drain 1-Wire IO; Pin 3 is GND; EP must be electrically and thermally connected to system ground.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 1-Wire memory applications.

Compared with DS28E80Q+T, DS28EC20+T offers greater memory capacity and endurance but zero gamma tolerance, while DS2431+T provides lower cost and simpler interface at the expense of radiation resilience and fine-grained write control-making DS28E80Q+T uniquely suited for pre-sterilization programmable medical traceability.

Availability

DS28E80Q+T is available at Aetrix Electronics and suitable for medical consumable identification, surgical tool calibration, point-of-care diagnostic authentication, and implantable device component tracking requiring stable component supply across global healthcare manufacturing programs.

Supply support for DS28E80Q+T 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, designs precision analog, mixed-signal, and digital ICs for industrial, medical, and communications applications.

The DS28E80Q+T belongs to Maxim's 1-Wire secure memory product line, engineered specifically for radiation-hardened, tamper-resistant identification and calibration in regulated medical device ecosystems.

FAQ

What is the maximum gamma radiation dose the DS28E80Q+T can withstand without data loss?

The DS28E80Q+T is rated for up to 75 kGy of gamma radiation exposure, enabling reliable pre-sterilization programming of calibration data, lot numbers, and UDI information. This specification is validated per JESD47G testing protocols and applies to the entire memory array-including user, administration, and protection memory-ensuring data retention remains intact after medical-grade sterilization cycles. DS28E80Q+T maintains full functionality and read/write capability post-irradiation.

How many times can each 8-byte block be written on the DS28E80Q+T?

Each of the 31 user memory blocks in the DS28E80Q+T supports exactly 8 write operations. The Read Remaining Cycles (A5h) command returns the remaining write count per block (00h = exhausted, 08h = unprogrammed). This finite endurance is intentional to balance radiation hardness and reliability-exceeding 8 writes per block is not supported and may result in undefined behavior or data corruption. DS28E80Q+T enforces this limit at the silicon level.

Does the DS28E80Q+T require an external power supply (VCC) or operate parasitically?

The DS28E80Q+T operates exclusively in parasitic power mode-it has no VCC pin and draws power from the 1-Wire bus via the IO pin during active communication. Its internal charge pump accumulates energy during bus idle (high) periods to power memory writes and logic functions. No external VCC connection is permitted or supported; the device is designed for single-wire simplicity in space-constrained medical accessories where adding a second power rail is impractical. DS28E80Q+T does not support active VCC operation.

Can write protection on the DS28E80Q+T be reversed or modified after activation?

No-write protection on the DS28E80Q+T is irreversible once set. The Write Protect Block (C3h) command permanently locks an 8-byte block, and subsequent attempts to reprogram that block return error code 55h. This one-time programmability ensures calibration data or regulatory identifiers cannot be altered post-manufacture. Protection status is verified via Read Block Protection (AAh), returning F0h for protected blocks and 0Fh for unprotected ones. DS28E80Q+T enforces this immutability at the hardware level.

What is the purpose of the exposed pad (EP) on the DS28E80Q+T TDFN package?

The exposed pad (EP) on the DS28E80Q+T serves dual thermal and electrical functions: it must be soldered uniformly to the PCB's ground plane to achieve specified thermal resistance (θJA = 60°C/W) and ensure stable operation under sustained 1-Wire communication loads. Electrically, EP connects internally to GND and provides low-impedance return path for IO switching currents-omitting or improperly soldering EP risks signal integrity degradation, timing violations, and potential device reset during overdrive-speed transactions. DS28E80Q+T requires EP grounding per JEDEC JESD51-7 guidelines.