DS28EC20+ - 20Kb 1-Wire EEPROM, TO-92-3 | Analog Devices
MPN: DS28EC20+ ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.85 | $2.85 |
| 10 | $2.65 | $26.50 |
| 100 | $2.4 | $240.00 |
| 500 | $2.18 | $1,090.00 |
| 1,000 | $2.05 | $2,050.00 |
DS28EC20+ Overview
A 1-Wire EEPROM is a serial non-volatile memory that combines data storage and communication on a single conductor plus ground, allowing multiple parts to share one bus and to be identified by a unique 64-bit ROM ID. The DS28EC20 belongs to the EEPROM -> non-volatile memory -> memory IC hierarchy within the broader semiconductor category, and it is one of the largest-density single-contact serial EEPROMs in the 1-Wire family, second only to higher-density siblings like the DS28CM00.
Key features include a wide operating range from 2.8 V to 5.25 V on VPUP, an operating temperature of -40 °C to +85 °C, a write endurance of 200k cycles per door, and over 40 years of data retention. The DS28EC20 also provides a high degree of backward compatibility with the legacy DS2433, requiring only a lengthening of tPROG from 5 ms to 10 ms, making it a popular migration target for retrofit designs that need more memory than 4 Kbit-class 1-Wire parts can offer. The TO-92-3 footprint suits through-hole PCB assemblies and probe-style mechanical enclosures.
The DS28EC20 uses a single-pin CMOS interface with internal parasitic-power charge-pump storage. The overdrive mode (4–5.25 V VPUP) enables faster factory programming and high-throughput identification, while standard mode supports long cable runs up to several meters. Its unique 64-bit ROM address and robust CRC-16 allow reliable device selection on a multidrop bus, simplifying firmware that needs to identify, authenticate, or store calibration data on a per-module basis.
Typical applications include per-board identification and traceability in industrial control modules, calibration and configuration storage in sensor assemblies, accessory authentication in medical and test equipment, firmware/license key storage in embedded systems, and tamper-evident parameter logging in metering devices. The 20 Kbit capacity is sufficient for storing calibration curves, user settings, audit logs, or small lookup blocks. When migrating from DS2433 (4 Kbit) or DS2431 (1 Kbit), the DS28EC20 is a 5x-20x density upgrade on the same 1-Wire protocol.
A key design tip is to add a 2.2 kΩ pull-up resistor on the 1-Wire data line to a regulated 3.3 V or 5 V rail (VPUP), and ensure your CRC-16 routine matches the device-generated polynomial so that multidrop bus contention is detected reliably.
This page synthesizes distributor pricing, same-package alternatives, and practical design notes not found in the manufacturer datasheet, giving procurement and design engineers an at-a-glance engineering reference for the DS28EC20+.
Drop-in alternatives for DS28EC20+ — 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 DS28EC20+ (same form factor and footprint) — differing in Interface, Memory Organization, Memory Size, Memory Type, Package.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
DS28EC20+T
✅ Drop-In✓ In Stock
$1.82 / Unit
View Datasheet →DS2433+
✅ Drop-In✓ In Stock
$1.92 / Unit
View Datasheet →DS28CM00+
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
DS2430A+
✅ Drop-In📋 Reference alternative (not in catalog)
DS28EC20+ Specifications
| Memory Type | Non-Volatile EEPROM (1-Wire) |
| Memory Size | 20 Kbit (20480 bit) |
| Memory Organization | 80 pages × 256 bits + 1 control page |
| Interface | 1-Wire (single-contact serial) |
| Standard Speed (max) | 15.4 kbps |
| Overdrive Speed (max) | 90 kbps |
| Operating VPUP Range | 2.8 V to 5.25 V (overdrive requires 4 V to 5.25 V) |
| Write Endurance | 200k cycles per page |
| Data Retention | >40 years |
| Scratchpad Size | 32 bytes |
| Programming Time (tPROG) | 10 ms (max) |
| Operating Temperature | -40 °C to +85 °C |
| Package | TO-92-3 (through-hole) |
| Mounting Type | Through Hole |
| RoHS Status | Compliant |
| Lead-Free Status | Yes |
| Unique 64-bit ROM ID | Yes (factory-lasered) |
| Backward Compatibility | DS2433 (4 Kbit 1-Wire EEPROM) |
DS28EC20+ Pin Configuration
| Pin 1 | GND — Ground reference |
| Pin 2 | DQ — 1-Wire data line (open-drain, requires external pull-up to VPUP) |
| Pin 3 | NC — No internal connection (mechanical pin only on TO-92-3 variant) |
Typical Applications
DS28EC20+ is suitable for 6 applications: Per-Board Identification & Traceability, Calibration & Configuration Storage, Accessory Authentication & Anti-Counterfeit, Firmware Parameter & License Key Storage, Tamper-Evident Metering & Audit Logs, Cable Identification & Patch-Panel Labeling.
Per-Board Identification & Traceability
The DS28EC20+ stores factory-lasered 64-bit ROM IDs and up to 20 Kbit of board-level identification data, including serial numbers, hardware revision codes, MAC addresses, and manufacturing lot data. The 1-Wire interface lets a single GPIO on the host MCU read every board on a multidrop bus during production testing, and the 200k write endurance supports field re-provisioning of asset tags throughout the product lifecycle. Unlike SPI/I²C parts, DS28EC20+ needs only one wire plus ground, reducing wiring in densely packed backplanes where each slot needs a unique ID.
Recommended
Calibration & Configuration Storage
The DS28EC20+ stores calibration constants, sensor trim values, and user configuration parameters for sensor modules, with 80 pages of 256 bits providing structured organization for sensor-specific data blocks. Its 32-byte scratchpad with read-back verification prevents partial programming under noisy power conditions - critical for factory calibration where data integrity is paramount. The 200k write endurance handles field re-calibration cycles over decades, and the -40 °C to +85 °C range matches industrial sensor operating environments.
Recommended
Accessory Authentication & Anti-Counterfeit
The DS28EC20+ factory-lasered 64-bit ROM ID provides a unique per-device identifier for accessory authentication in medical devices, test equipment, and consumable cartridges. The 20 Kbit capacity stores additional challenge-response data or authentication certificates, and the 1-Wire interface supports cable runs up to several meters for probe-style accessories. Its >40 year data retention ensures authentication keys remain valid across the entire product lifecycle, while CRC-16 integrity checking detects tampering attempts on the multidrop bus.
Recommended
Firmware Parameter & License Key Storage
The DS28EC20+ stores firmware configuration parameters, feature-license keys, and boot-time defaults that must survive power-cycle and firmware-reflash operations. Its 20 Kbit capacity is sufficient for storing product feature flags, regional settings, and serial-number-based license keys for embedded devices in industrial automation. The 1-Wire bus allows the host MCU to read parameters at boot using only one GPIO, freeing dedicated I²C/SPI pins for higher-speed peripherals and reducing BOM cost on cost-sensitive embedded designs.
Recommended
Tamper-Evident Metering & Audit Logs
The DS28EC20+ stores tamper-evident audit logs in metering devices (electricity, water, gas), capturing timestamped events, cumulative readings, and tamper-counter values that must survive power loss and physical tampering. Its 200k write endurance supports frequent event logging over the meter's 15-20 year service life, and the >40 year data retention ensures legal-grade record preservation. The 1-Wire interface allows field readers to extract logs via a probe contact without opening the meter, while the unique ROM ID prevents record substitution attacks.
Recommended
Cable Identification & Patch-Panel Labeling
The DS28EC20+ in the through-hole TO-92 package can be embedded inside cable assemblies and wire harnesses for unique cable identification, storing cable length, gauge, shielding class, and test-result data. The 1-Wire interface supports cable runs up to several meters, enabling diagnostic tools to query cable identity from the rack end without disconnecting. The TO-92-3 footprint allows the EEPROM to be molded directly into the connector backshell or cable jacket, providing a rugged embedded serial number for datacenter and broadcast applications.
Recommended
Recommended Products Summary
Engineering reference data for DS28EC20+ — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | DS28EC20+T | DS2433+ | DS28CM00+ | DS2430A+ |
|---|---|---|---|---|---|
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Package | TO-92-3 | TO-92-3 - same | TO-92-3 - same | TO-92-3 - same | TO-92-3 - same |
| Memory Size | 20 Kbit | 20 Kbit | 4 Kbit | 256 bit | 256 bit |
| Interface | 1-Wire | 1-Wire | 1-Wire | 1-Wire | 1-Wire |
| Standard Speed (max) | 15.4 kbps | 15.4 kbps | 16.3 kbps | 15.4 kbps | 16.3 kbps |
| Overdrive Speed (max) | 90 kbps | 90 kbps | Not supported | 90 kbps | Not supported |
| Operating Voltage | 2.8 V to 5.25 V | 2.8 V to 5.25 V | 2.8 V to 6.0 V | 2.8 V to 5.25 V | 2.8 V to 6.0 V |
| Programming Time (tPROG max) | 10 ms | 10 ms | 5 ms | 10 ms | 10 ms |
| Write Endurance | 200k cycles/page | 200k cycles/page | 200k cycles/page | 200k cycles/page | 200k cycles/page |
| 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 |
Key Differentiators
- Highest-density 1-Wire EEPROM in TO-92-3 package from same family (vs DS2433+)
- Same TO-92-3 footprint as legacy DS2433 for backward-compatible migration (vs DS28CM00+)
- Supports 90 kbps overdrive mode for factory programming throughput (vs DS2430A+)
- Wider VPUP operating range than legacy 1-Wire parts (vs DS2433+)
Design Notes
Estimated: The DS28EC20+ draws parasitic power from the DQ line through an internal charge pump, so a stable pull-up supply (VPUP) between 2.8 V and 5.25 V is mandatory. For overdrive mode (90 kbps), VPUP must be 4-5.25 V because the charge pump needs extra headroom for faster clock recovery. Use a 2.2 kΩ pull-up resistor on DQ to a regulated rail, and add 100 nF decoupling on VPUP near the device for bus-stabilization during strong pulldown events. Inadequate pull-up strength is the #1 cause of CRC-16 errors on long cable runs.
The TO-92-3 footprint should be placed with pin 1 (GND) tied to a low-inductance ground return, pin 2 (DQ) routed with short trace to the host MCU GPIO with the 2.2 kΩ pull-up placed within 5 mm of the device. For multidrop buses, use a star-topology or daisy-chain with stubs shorter than 1/10 of the rise time to prevent signal reflections. Keep the DQ trace away from switching power and high-current traces to avoid coupled noise that the weak pull-up cannot reject. A 4.7 kΩ pull-up may be substituted for very long cable runs (>5 m) at the cost of reduced noise margin.
Common pitfalls: (1) Forgetting that the 1-Wire CRC-16 is computed by the device, not the host - the host must verify it on every read transaction. (2) Confusing the TO-92-3 pinout with through-hole transistors - the asymmetric silhouette prevents reversal, but double-check during hand assembly. (3) Programming time tPROG is 10 ms (max) for DS28EC20, NOT 5 ms as on the legacy DS2433 - this is the only protocol change required for backward-compatible migration. (4) Overdrive mode requires VPUP ≥ 4 V; using standard mode below 4 V silently downgrades throughput to 12 kbps.
Estimated: For cable runs longer than 1 meter, add a 100 Ω series resistor at the host end of the DQ line to dampen ringing, and use shielded twisted-pair cable with the shield tied to ground at the host end only. The DS28EC20+ overdrive mode at 90 kbps has a rise time of approximately 1 µs, so the stub-length budget at 90 kbps is roughly 1.5 m before reflections become visible. For multidrop buses with more than 5 devices, split the bus into segments and use repeaters to maintain signal integrity.
Compliance Information
RoHS compliant per Analog Devices product page. Lead-free (Pb-free) confirmed. Halogen-free status not explicitly stated in retrieved web data. Not AEC-Q100 qualified - this is a commercial/industrial-grade part. For automotive applications, contact Analog Devices sales for AE/JLC variants.
