Analog Devices Inc./Maxim Integrated DS28E04S-100+

Overview

DS28E04S-100+ from Maxim Integrated (now Analog Devices) is a 4096-bit, 1-Wire® EEPROM with two general-purpose open-drain PIO pins (P0/P1), seven address inputs (A0–A6), and parasitic or V_CC-powered operation. It provides device-level physical location encoding via direct mapping of address bits into the 64-bit Device ID, supports EPROM-emulation mode (write-to-0), and enables conditional search based on PIO state or activity - used in modular telecom systems for autoconfiguration and PCB identification.

For engineers reviewing the DS28E04S-100+ datasheet, DS28E04S-100+ pinout, DS28E04S-100+ application, or DS28E04S-100+ equivalent, key selection criteria include 1-Wire bus compatibility at 15.3/111 kbps, individual page write protection, pulse-generation capability on PIO pins, wide 2.8V–5.25V supply range, and -40°C to +85°C industrial temperature operation.

Technical Context

The DS28E04S-100+ implements a fully compliant Maxim 1-Wire protocol stack with ROM function command hierarchy (e.g., Conditional Search ROM, Match ROM) and memory/control function layer (e.g., Copy Scratchpad, PIO Access Write). Its 16-page EEPROM (32 bytes/page) uses a volatile 32-byte scratchpad buffer and supports write protection and EPROM-emulation modes per page via dedicated control registers at 0200h–020Fh.

PIO functionality is managed through volatile registers at 0220h–0225h: logic state (0220h), output latch (0221h), activity latch (0222h), and conditional search configuration (0223h–0225h). Pulse generation requires V_CC power; activity latches capture edge transitions >1 µs; and conditional search evaluates AND/OR logic across selected PIO channels using polarity and source (pin vs. latch) configuration.

Key Specifications

Pinout & Package

DS28E04S-100+ is housed in a 16-pin, 150-mil SOIC package with exposed pad not electrically connected. Pin functions are validated per Maxim's official DS28E04-100 datasheet Rev 12/11.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 1-Wire EEPROM with PIO applications.

Compared with DS28E04S-100+, DS28E05S-100+ offers double memory capacity in pin-compatible form for future-proofing, while DS2430A+ sacrifices all advanced features for minimal footprint and BOM cost - making DS28E04S-100+ the optimal balance of intelligence, I/O flexibility, and industrial reliability.

Availability

DS28E04S-100+ is available at Aetrix Electronics and suitable for telecom infrastructure, optical networking equipment, and industrial PCB identification requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for DS28E04S-100+ 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

Analog Devices (via acquisition of Maxim Integrated) designs precision analog, mixed-signal, and digital ICs for industrial, automotive, and communications markets - emphasizing reliability, low-power operation, and system-level integration.

The DS28E04S-100+ belongs to Maxim's 1-Wire secure memory family, engineered specifically for distributed identification, configuration, and state monitoring in multi-drop wired networks where wiring simplicity and device-level uniqueness are critical.

FAQ

What is the maximum 1-Wire bus speed supported by the DS28E04S-100+?

The DS28E04S-100+ supports two 1-Wire communication speeds: standard mode at 15.3 kbps and overdrive mode at 111 kbps. Overdrive mode is entered after issuing an Overdrive-Skip ROM or Overdrive-Match ROM command and requires compatible bus master hardware like the DS2482-100 or DS2490. The DS28E04S-100+ maintains full protocol compliance including presence detection, reset timing, and CRC16 validation at both speeds.

Can the DS28E04S-100+ operate without an external V_CC supply?

Yes, the DS28E04S-100+ operates in parasitic power mode using energy harvested from the 1-Wire bus via the IO pin - sufficient for EEPROM reads, writes, and PIO input sensing. However, V_CC is mandatory for PIO pulse generation and maintaining PIO output states during bus idle periods. When V_CC is absent, pulse commands will fail and output latches reset on power loss.

How does the DS28E04S-100+ ensure unique identification in a multi-device 1-Wire network?

The DS28E04S-100+ guarantees uniqueness via its 64-bit Device ID: 8-bit family code (1Ch), 8-bit external address (with user-configurable A0–A6), 40-bit factory-lasered serial number, and 8-bit CRC. Even if multiple units share identical A0–A6 wiring, the 40-bit serialized field prevents address collisions - enabling reliable individual addressing in networks with dozens of devices on a single bus.

What happens when a write-protected page is targeted during a Copy Scratchpad command on the DS28E04S-100+?

When a Copy Scratchpad command targets a write-protected page on the DS28E04S-100+, the operation proceeds successfully but has no effect on the protected EEPROM contents. The device copies the scratchpad data into the target page only if protection is disabled (control byte ≠ 55h or AAh). If protection is active, the existing EEPROM data remains unchanged - allowing safe refresh attempts without risk of corruption.

Does the DS28E04S-100+ support hardware-based conditional search based on PIO activity?

Yes, the DS28E04S-100+ includes dedicated hardware logic for conditional search based on PIO activity latches. By configuring registers at 0223h–0225h (selection mask, polarity, and control bits), the device autonomously responds to Search ROM commands only when specified PIO edges occur - eliminating host software polling and reducing bus traffic in large-scale monitoring systems.