DS2431G+U - 1Kb 1-Wire EEPROM, 2-SFN Package | Analog Devices
MPN: DS2431G+U ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.34 | $2.34 |
| 10 | $2.15 | $21.50 |
| 100 | $1.86 | $186.00 |
| 500 | $1.62 | $810.00 |
| 1,000 | $1.45 | $1,450.00 |
DS2431G+U Overview
What is a 1-Wire EEPROM? A 1-Wire EEPROM is a non-volatile memory device that uses Maxim's proprietary 1-Wire protocol, which combines power and bidirectional data on a single conductor plus ground. This dramatically simplifies wiring in identification, calibration, and accessory-detect applications by eliminating the multi-pin SPI/I²C bus. The hierarchy is: 1-Wire EEPROM -> serial EEPROM -> non-volatile memory (NVM) -> memory IC -> semiconductor. Each 1-Wire device also carries a unique 64-bit ROM ID, enabling multi-drop addressing on a single bus.
Key features of the DS2431G+U include four 256-bit memory pages that can be individually write-protected or put into EPROM-emulation mode (bits can only change from 1 to 0), a unique factory-lasered 64-bit ROM identification number, 8-byte scratchpad for verified write-then-copy operation, and full compatibility with the 1-Wire protocol used throughout the iButton®/1-Wire ecosystem. The 2-SFN package exposes a single DQ data/power contact and a GND paddle, making it ideal for compact PCB pads or solder-down identification tokens.
Architecturally, the DS2431 uses an on-chip silicon unique-ID ROM (8-byte family code + 6-byte serial number + 1-byte CRC) generated at wafer probe, plus a four-page EEPROM array accessed through an 8-byte SRAM scratchpad. Writes go through the scratchpad with a built-in 8-bit CRC verification before being copied atomically to the target page, which gives robust data integrity for in-field updates.
Typical applications include PCB identification and asset tagging, consumable authentication (ink cartridges, medical disposables, batteries), board-level calibration storage, secure feature enablement, and iButton/1-Wire bus identification nodes. The DS2431G+U is the SFN-packaged member of the broader DS2431 family that also ships in TO-92, TSOC, and TDFN packages.
When designing with the DS2431G+U, ensure the DQ line has a strong pull-up (typically 4.7 kΩ to VPU) for both power delivery and open-drain signaling, and reserve host-side firmware for the MATCH ROM / SKIP ROM / WRITE SCRATCHPAD / READ SCRATCHPAD / COPY SCRATCHPAD command sequence. Strong ESD and surge protection on the DQ contact is recommended for connector-exposed applications; the DS2431 family is well documented in Maxim/Analog Devices Application Note 3829.
This page synthesizes distributor pricing, drop-in package-compatible alternatives, and practical design notes not found in the standalone manufacturer datasheet.
Drop-in alternatives for DS2431G+U — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with DS2431G+U (same form factor and footprint) — differing in Interface, Memory Organization, Memory Size, Memory Type, Mounting Type.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
DS2431G+T
✅ Drop-In📋 Reference alternative (not in catalog)
DS2431G/V+
✅ Drop-In📋 Reference alternative (not in catalog)
DS2431G+U
✅ Drop-In✓ In Stock
$1.45 / Unit
View Datasheet →DS2431GA1+
✅ Drop-In📋 Reference alternative (not in catalog)
DS2431GA3+
✅ Drop-In📋 Reference alternative (not in catalog)
DS2430A+
✅ Drop-In📋 Reference alternative (not in catalog)
DS28EC20+
✅ Drop-In✓ In Stock
$2.05 / Unit
View Datasheet →DS2431G+U Maximum Ratings & Electrical Characteristics
| Memory Type | EEPROM (Non-Volatile) |
| Memory Size | 1 Kbit (1024 bits) |
| Memory Organization | 4 pages x 256 bits (32 bytes) |
| Interface | 1-Wire® (single-contact DQ + GND) |
| Write Cycle Time | 2 µs (scratchpad write) |
| Scratchpad Size | 8 bytes (64 bits) |
| Unique ROM ID | 64-bit (8-byte family code + 6-byte serial + CRC) |
| Write Protection | Per-page, selectable; EPROM-emulation mode (1→0 only) |
| Package | 2-SFN (6.0 mm x 6.0 mm leadless) |
| Operating Temperature | -40 °C to +85 °C |
| Storage Temperature | -55 °C to +125 °C (per datasheet Absolute Maximum Ratings) |
| Supply (Parasite Power via DQ) | 2.8 V to 5.25 V (pull-up VPU) |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
| Lead-Free / Halogen-Free | Yes / Yes |
DS2431G+U Pin Configuration
| Pin 1 | DQ — 1-Wire data and parasite power contact |
| Pin 2 | GND — Ground and exposed bottom pad (thermal/mechanical reference) |
Typical Applications
DS2431G+U is suitable for 7 applications: PCB Identification and Asset Tagging, Consumable Authentication and Anti-Counterfeit, Calibration Data Storage, iButton / 1-Wire Multi-Drop Identification, Accessory Detection and Cartridge Recognition, Industrial Sensor Module Identity, Battery Pack Identification and Cycle Logging.
PCB Identification and Asset Tagging
The DS2431G+U's 64-bit factory-lasered ROM ID and 1024-bit EEPROM make it the canonical 1-Wire tagging device for PCB identification and asset tracking. Soldered onto every board, it lets a host firmware image automatically detect board revision, manufacture date, and MAC/serial assignments via the MATCH ROM and READ ROM commands. Its 2-SFN 6x6 mm land pattern occupies less board area than a TO-92 iButton, fitting beneath BGA shadow regions. The parasite-powered single DQ line keeps BOM cost to one pull-up resistor, suiting high-volume consumer and industrial electronics.
Recommended
Consumable Authentication and Anti-Counterfeit
OEM consumables - printer toner, medical sensors, battery packs, ink cartridges - embed the DS2431G+U as a cryptographic-authentication token. The unique 64-bit ROM ID plus the 1-Kbit EEPROM enable per-unit challenge/response secrets and consumable-life counters in EPROM-emulation mode. The 2 µs scratchpad-write time supports fast in-line production programming. Per-page write protection lets OEMs lock calibration constants while leaving a small region for end-user cycle counters.
Recommended
Calibration Data Storage
Precision analog front ends and sensor modules use the DS2431G+U to store factory calibration coefficients that the host reads at power-up. The four 256-bit pages map neatly to gain, offset, linearity, and lot-traceability records. EPROM-emulation mode provides tamper-evident one-way logging of field events. Because the device rides a single DQ line, calibration is supported on test fixtures without breaking into the main SPI/I2C bus.
Recommended
iButton / 1-Wire Multi-Drop Identification
In door-lock, weighing-scale, or handheld-instrument cradles, the DS2431G+U acts as the identification token while the host uses the DS2482 or DS2480B bridge to poll. Up to dozens of 1-Wire devices can co-exist on a single DQ line because each carries a unique ROM ID resolved by SEARCH ROM. The 2-SFN package supports flat spring-contact probe readers, replacing the older TO-92 iButton footprint for slimmer handheld designs.
Recommended
Accessory Detection and Cartridge Recognition
Modular systems (handheld scanners, medical disposables, vacuum tool heads) use the DS2431G+U in each accessory to advertise its identity, firmware profile, and lifetime counters. Because the device is parasite-powered, the host's cradle connector needs only a single spring-loaded probe, dramatically reducing mechanical BOM and improving ingress-protection ratings. EPROM-emulation mode doubles as a one-way usage counter that cannot be reset by end users.
Recommended
Industrial Sensor Module Identity
Distributed 1-Wire sensor chains in building automation and HVAC use the DS2431G+U to provide unique identity and runtime configuration storage on each node. The 1-Kbit capacity supports a unique 64-bit ID, a sensor type code, calibration coefficients, and a CRC-protected configuration record. Operating temperature -40 °C to +85 °C handles unconditioned plant environments, and the 2-SFN package is far smaller than DS18B20-style TO-92 sensor cans.
Recommended
Battery Pack Identification and Cycle Logging
Smart battery packs include a DS2431G+U to store chemistry, lot code, and a one-way cycle counter using EPROM-emulation mode where each charge cycle burns one bit from 1 to 0. The parasite-powered single-line interface keeps wiring to a single spring contact on the host connector, supporting sealed IP67 battery designs. Page-level write protection lets OEMs lock chemistry/safety fields while leaving the cycle counter writable.
Recommended
Recommended Products Summary
Engineering reference data for DS2431G+U — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | DS2431G+T | DS2431G/V+ | DS2430A+ | DS28EC20+ |
|---|---|---|---|---|---|
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Package | 2-SFN (6x6 mm) | 2-SFN (6x6 mm) - same | 2-SFN (6x6 mm) - same | 2-SFN (6x6 mm) - same | 2-SFN (6x6 mm) - same |
| Memory Size | 1 Kbit | 1 Kbit | 1 Kbit | 256 bit (-75%) | 20 Kbit (+1920%) |
| Memory Organization | 4 pages x 256 bits | 4 pages x 256 bits | 4 pages x 256 bits | 1 page x 256 bits | 4 pages x 512 bytes |
| Interface | 1-Wire | 1-Wire | 1-Wire | 1-Wire | 1-Wire |
| Unique ROM ID | 64-bit | 64-bit | 64-bit | 64-bit | 64-bit |
| Operating Temperature | -40 °C to +85 °C | -40 °C to +85 °C | -40 °C to +85 °C | -40 °C to +85 °C | -40 °C to +85 °C |
| Programming | 8-byte scratchpad, 2 µs write | 8-byte scratchpad, 2 µs write | 8-byte scratchpad, 2 µs write | 8-byte scratchpad | 32-byte scratchpad |
| RoHS Compliance | Yes | Yes | Yes | Yes | Yes |
Key Differentiators
- Lowest wire count among all EEPROM categories (vs DS2430A+)
- Higher density than the legacy DS2430A in same footprint (vs DS2430A+)
- Right-sized density (1 Kbit) for typical authentication use cases (vs DS28EC20+)
- Faster scratchpad writes than DS2430A (vs DS2430A+)
- Stable, mainstream 1-Wire family part (vs DS28EC20+)
Design Notes
The DQ contact of the DS2431G+U is the only electrical interface, so PCB land-pattern fidelity is critical. Keep the DQ trace short and away from switching converters to avoid noise during scratchpad writes. Place the 4.7 kΩ pull-up resistor (R_PU) within a few millimeters of the device when possible; long DQ traces can exceed 1-Wire timing budgets on multi-node buses. Use a 4-layer board with a solid ground plane beneath the SFN pad.
If the DQ line is exposed to user contact (cable, battery door, cradle), add a TVS diode (e.g., SMAJ5.0CA) between DQ and GND to protect the open-drain driver and parasite-power rectifier. The DS2431G+U has limited internal ESD rating, so external protection is essential for consumer and medical applications. Keep the TVS capacitance below 100 pF to avoid loading the 1-Wire rise time.
Avoid reading the EEPROM page directly - the host must always go through the 8-byte scratchpad with READ SCRATCHPAD + CRC verification before issuing COPY SCRATCHPAD. Skipping the scratchpad pattern is the #1 cause of silent data corruption in 1-Wire designs. Also, when computing the 8-bit CRC over the scratchpad, use the Maxim polynomial 0x8C (X^8 + X^5 + X^4 + 1), not CRC-16 or CRC-32. Reference Application Note 3829 for full command set.
Estimated: at VPU = 5 V, the DS2431G+U draws approximately 1.5 mA peak during COPY SCRATCHPAD to EEPROM (the worst-case EEPROM write). Ensure the host pull-up can source this current - a passive 4.7 kΩ to 5 V yields about 1 mA which may be marginal. For reliable writes, use an active pull-up (P-MOSFET switched by the host) to deliver a hard 5 V during writes, especially on long cables. Refer to AN-3829 for active-pull-up schematics.
The 2-SFN package is a small thermal mass and self-heating during EEPROM writes is minimal. However, in reflow-profile manufacturing, the exposed bottom pad should receive standard SAC2828 lead-free profile per JEDEC J-STD-020. Hand-soldering is not recommended for production volumes due to the small land area. Use no-clean flux and verify no solder balls bridge the DQ pad to GND.
Compliance Information
RoHS and halogen-free per Heisener/Veswin distributor listings and Analog Devices product page. Industrial temperature grade (-40 °C to +85 °C); for AEC-Q100 qualified flow, choose the DS2431G/V+ variant instead.
