DS28E25+ - SHA-256 1-Wire Authenticator, 4Kb EEPROM, TO-92 | Analog Devices
N.º da peça: DS28E25+ ✓ Ativo| Qtd. | Preço unitário | Total |
|---|---|---|
| 1 | $3.04 | $3,04 |
| 10 | $2.85 | $28,50 |
| 100 | $2.55 | $255,00 |
| 500 | $2.3 | $1.150,00 |
| 1.000 | $2.1 | $2.100,00 |
DS28E25+ Visão geral
A secure authenticator is a specialized IC category within the broader semiconductor security hierarchy: secure authenticator -> cryptography IC -> security IC -> interface/specialized IC. DeepCover is Analog Devices' portfolio of security ICs that embed cryptographic primitives, physically secure key storage, and active die-level shielding to protect against invasive and non-invasive attacks, addressing system-on-board (SoB) and peripheral-authentication use cases where a software-only root-of-trust is insufficient.
Key features include hardware SHA-256 computation over user memory, a 64-bit secret, a host random challenge, and the 64-bit ROM ID; on-chip 4 Kb (512-byte) user EEPROM organized in 32 pages of 16 bytes; 1-Wire overdrive communication up to 76.9 kbps; a unique factory-lasered 64-bit registration number; and write-only/read-only protection modes per page. The TO-92 package is chosen for cable-mounted peripherals (medical sensors, printer cartridges, e-meter modules) where the authenticator is soldered or clipped onto a flying lead and survives harsh mechanical environments.
Architecturally, the DS28E25 isolates the secret in a protected memory block that participates in the SHA-256 hash but is never exposed on the bus. Host-side verification reads the public EEPROM, generates a random challenge, computes SHA-256 in firmware, and compares the result with the device-returned MAC - a strong two-factor scheme where knowledge of the secret alone cannot impersonate the device without the physical silicon.
Typical applications include medical sensor authentication (single-use disposable probes), printer and consumable cartridge identification, industrial control module anti-counterfeiting, e-meter tamper detection, and IoT node provisioning. In each case the DS28E25+ provides a hardware root-of-trust that is impractical to clone.
When designing with this part, place a strong pull-up (typically 4.7 kohm to VPUP, the 1-Wire pull-up rail) on the data line, observe the VPUP range of 2.97 V to 3.63 V during reads and EEPROM writes, and verify parasitic-power budgeting during long EEPROM-programming intervals where current can reach several milliamps. Decoupling on the VPUP rail with a 0.01 uF to 0.1 uF ceramic capacitor close to the device improves write reliability.
This page synthesizes distributor pricing, drop-in alternatives from the same product family and competitor equivalents, and practical design notes not found in the manufacturer datasheet.
Alternativas drop-in para DS28E25+ — mesmo encapsulamento, compatível pino a pino. Peças de encapsulamento diferente que exigem retrabalho na PCB são excluídas.
Variantes desta série
Modelos da mesma série compatíveis como drop-in com DS28E25+ (mesmo formato e footprint) — diferindo em Mounting Type, Package, Product Type, Security Features, User EEPROM.
Ferramenta de comparação rápida — selecione peças alternativas para comparação lado a lado:
DS28E25P+
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
DS28E22+
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
DS28E25Q+T&R
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
DS28E25EVKIT
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
DS28C36Q+T&R
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
DS28E25+ Classificações máximas e características elétricas
| Product Type | Secure Authenticator / SHA-256 Co-Processor |
| Family | DeepCover Secure Authenticator |
| Interface | 1-Wire (single-contact, half-duplex) |
| 1-Wire Speeds | Standard and Overdrive |
| Cryptographic Algorithm | SHA-256 (FIPS 180-4) |
| User EEPROM | 4 Kbit (512 bytes, 32 pages x 16 bytes) |
| ROM ID | 64-bit factory-lasered unique registration number |
| Operating Voltage (VPUP) | 2.97 V to 3.63 V |
| Parasite Power | Yes (powered from 1-Wire data line) |
| Encapsulamento | TO-92-2 (TO-226AC), 3 pins |
| Tipo de montagem | Through-Hole |
| Temperatura de operação | -40 C to +85 C |
| Status RoHS | Compliant |
| Security Features | Hardware SHA-256, on-chip secret storage, active die shield |
Configuração de pinos do DS28E25+
| Pino 1 | GND — Ground reference |
| Pino 2 | IO — 1-Wire data line and parasitic power input (VPUP) |
| Pino 3 | NC — No internal connection (leave floating or tie to GND) |
Aplicações típicas
DS28E25+ é adequado para 6 aplicaçãos: Medical Sensor Authentication, Printer & Consumable Cartridge Identification, Industrial Control Module Anti-Counterfeiting, Smart Energy Meter Tamper Detection, IoT Node Provisioning & Secure Boot, Automotive Accessory Authentication.
Medical Sensor Authentication
Disposable medical sensors (pulse-oximeter probes, ECG leads, glucose strips) require per-unit authentication to prevent counterfeit accessories from being used with regulated medical equipment. The DS28E25+ is ideal for this role because its TO-92 through-hole package can be overmolded directly into the sensor cable assembly, surviving autoclave sterilization. The hardware SHA-256 engine computes a 32-byte MAC from the 64-bit ROM ID, an on-chip secret, a host random challenge, and 4 Kbit of user EEPROM - enough to store calibration coefficients, lot codes, and expiration dates. Each probe is verified by the host in under 1 ms over standard 1-Wire speed, ensuring no perceptible delay at clinical workflow.
Recomendado
Printer & Consumable Cartridge Identification
Inkjet and toner cartridges must be authenticated to prevent third-party refills from damaging printheads or voiding warranties. The DS28E25+ integrates into the cartridge cable harness via its TO-92 package, with a single data wire carrying both communication and parasite power. The host printer issues a random challenge on every power-up; the DS28E25+ returns a SHA-256 MAC that the printer's DS2465 host coprocessor verifies against the expected value. The 4 Kbit EEPROM stores fill level, ink chemistry, and warranty counters, while the factory-locked 64-bit ROM ID provides cryptographic identity. EEPROM EPROM-emulation mode ensures calibration data cannot be rewritten once sealed.
Recomendado
Industrial Control Module Anti-Counterfeiting
Industrial PLCs, motor drives, and sensor modules ship with replaceable subassemblies that vendors must authenticate to prevent counterfeit replacements from causing field failures. The DS28E25+ provides the cryptographic root-of-trust: each subassembly carries its own DS28E25+ with a unique 64-bit ROM ID and on-chip secret. The host controller generates a 256-bit random challenge and verifies the SHA-256 MAC over the 1-Wire bus. The TO-92 package is rated -40 C to +85 C, suitable for industrial cabinet environments. The active die shield and on-chip secret storage protect against invasive attacks, while the 4 Kbit EEPROM stores calibration coefficients and vendor certificates.
Recomendado
Smart Energy Meter Tamper Detection
Electricity, gas, and water meters must detect physical tampering attempts including cover removal and magnetic interference. The DS28E25+ embedded in the meter's tamper-evident enclosure provides authentication that proves the meter has not been opened or replaced: each communication carries a SHA-256 MAC that can only be computed by the genuine DS28E25+ with its factory-programmed secret. The TO-92 form factor survives the meter production line (wave-solderable through-hole) and the 30-year operating life of utility meters. The 4 Kbit EEPROM stores usage logs, calibration tables, and tamper-event counters protected by SHA-256 integrity verification.
Recomendado
IoT Node Provisioning & Secure Boot
IoT sensor nodes deployed in the field require per-device identity and firmware authentication to prevent malicious re-flashing. The DS28E25+ provides the hardware root-of-trust: each node's MAC address, certificate, and firmware signature is stored in the 4 Kbit user EEPROM and verified at boot via SHA-256 over the 1-Wire bus. The TO-92 package is small enough for even coin-cell powered IoT nodes, and the parasitic-power architecture means only one wire is needed from the host MCU. The factory-unique 64-bit ROM ID serves as the device certificate serial number. The 1-Wire overdrive speed (76.9 kbps) keeps authentication under 1 ms, allowing fast boot times.
Recomendado
Automotive Accessory Authentication
OEM automotive accessories (dash cameras, diagnostic dongles, infotainment modules) must authenticate to the head unit to enable premium features and prevent warranty fraud from incompatible third-party hardware. The DS28E25+ embedded in the accessory provides cryptographic identity over the 1-Wire bus already present on the OBD-II / accessory cable. The hardware SHA-256 MAC is computed from the on-chip secret, host challenge, 4 Kbit user EEPROM (storing serial number, model code, firmware version), and 64-bit ROM ID. The TO-92 package tolerates under-hood temperatures up to +85 C in protected locations. Note: the standard DS28E25+ is not AEC-Q100 qualified; consult Analog Devices for the latest automotive-grade DeepCover variants.
Recomendado
Resumo dos produtos recomendados
Dados de referência de engenharia para DS28E25+ — comparação, orientação de projeto e informações de conformidade.
Guia de seleção
Comparação com alternativas
| Parâmetro | Este produto | DS28E25P+ | DS28E22+ | DS28E25Q+T&R | DS28E25EVKIT | DS28C36Q+T&R |
|---|---|---|---|---|---|---|
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Package | TO-92-2 (TO-226AC) | TO-92-2 - same | TO-92-2 - same | TO-92-2 - same | TO-92 (eval board) - same IC | TO-92 variant Q - same |
| Cryptographic Algorithm | SHA-256 (FIPS 180-4) | SHA-256 - same | SHA-1 (weaker) | SHA-256 - same | SHA-256 - same | SHA-256 - same |
| User EEPROM | 4 Kbit (512 bytes) | 4 Kbit - same | 4 Kbit - same | 4 Kbit - same | 4 Kbit - same | 8 Kbit (2x density) |
| ROM ID Width | 64-bit | 64-bit - same | 64-bit - same | 64-bit - same | 64-bit - same | 64-bit - same |
| Operating Voltage (VPUP) | 2.97 V to 3.63 V | 2.97 V to 3.63 V - same | 2.97 V to 3.63 V - same | 2.97 V to 3.63 V - same | 2.97 V to 3.63 V - same | 2.97 V to 3.63 V - same |
| 1-Wire Speeds | Standard + Overdrive (76.9 kbps) | Standard + Overdrive - same | Standard + Overdrive - same | Standard + Overdrive - same | Standard + Overdrive - same | Standard + Overdrive - same |
| Mounting Type | Through-Hole (TO-92) | Through-Hole - same | Through-Hole - same | Through-Hole - same | Eval Board (PCB) | Through-Hole - same |
| Additional Features | None | Same as base | SHA-1 (no SHA-256) | Tape-and-reel packaging | USB-to-1-Wire + sample ICs | GPIO + battery RTC + 8Kb EEPROM |
| Lifecycle Status | Active | Active | Active | Active | Active | Active |
Principais diferenciais
- SHA-256 cryptographic strength vs SHA-1 alternative (vs DS28E22+)
- TO-92 through-hole package vs SMD-only alternatives (vs DS28C36Q+T&R)
- Self-contained crypto engine vs host-only software SHA-256 (vs Discrete MCU-based SHA-256)
Notas de projeto
The DS28E25+ operates from VPUP (2.97 V to 3.63 V) supplied through the 1-Wire data/parasitic-power line. During EEPROM programming the device draws several milliamps and the VPUP rail must remain in regulation for the entire write interval (typically 5-10 ms per page). Use a low-impedance pull-up (4.7 kohm typical to 3.3 V) and a 0.1 uF ceramic decoupling capacitor placed within 5 mm of the IO pin to prevent VPUP droop during writes. For long cable runs (>1 m), increase the decoupling to 1 uF and use a stronger pull-up (2.2 kohm).
A common design error is leaving the NC pin (pin 3 of the TO-92 package) floating in noisy environments. Although the pin has no internal connection, capacitive coupling into the silicon substrate can shift the SHA-256 MAC computation timing by tens of microseconds. Best practice is to tie the NC pin to GND at the PCB or cable. Additionally, ensure the host-side 1-Wire master issues the correct read-ROM and match-ROM commands per the DS28E25 datasheet - the device will not respond to incorrect command bytes and may enter an undefined state if CRC checks fail.
When the DS28E25+ is mounted on a flying lead (typical for disposable medical and printer consumable applications), keep the IO wire as short as practical (under 300 mm preferred, 1 m maximum at standard 1-Wire speed) and avoid running it parallel to AC power lines or switching-converter nodes. Twisted-pair cable with the IO line paired to a ground return reduces radiated emissions and improves noise immunity. Add a 50-ohm series resistor at the host MCU end of long cables to dampen transmission-line reflections; the TO-92 package lead inductance (~10 nH) does not need external snubbing at 1-Wire standard speed.
Informações de conformidade
RoHS and REACH compliance per Analog Devices product page. Not AEC-Q100 qualified - choose an automotive-grade DeepCover variant for vehicle applications. Halogen-free status not explicitly stated in verified data.
