Analog Devices Inc./Maxim Integrated DS2430A+

Overview

DS2430A+ from Analog Devices is a 256-bit 1-Wire EEPROM with integrated 64-bit unique ROM (family code 14h), 64-bit one-time programmable application register, and parasitic power operation. It operates from 2.8V to 5.25V across –40°C to +85°C in TO-92 package, communicating at up to 14.3 kbps via single-wire interface for board identification and calibration storage.

For engineers reviewing the DS2430A+ datasheet, DS2430A+ pinout, DS2430A+ application, or DS2430A+ equivalent, key selection criteria include 1-Wire bus compatibility, TO-92 mechanical fit, parasitic power capability, 256-bit EEPROM page structure, and application register lock behavior.

Technical Context

The DS2430A+ implements a hierarchical 1-Wire protocol requiring ROM function commands (e.g., Skip ROM CCh, Match ROM 55h) before memory access. Its internal architecture includes separate scratchpad buffers for 256-bit EEPROM and 64-bit application register, with status register (FFh pre-lock, FCh post-lock) indicating write-protection state.

Communication relies on open-drain signaling with strict timing: tW0L ≥ 60 µs for Write-0, tW1L ≤ 15 µs for Write-1, and controller sampling window tMSR between 15 µs and 60 µs after tRL expiration. Noise immunity is enhanced by VTH hysteresis (VHY) and rising-edge hold-off time (tREH).

Key Specifications

Pinout & Package

DS2430A+ uses a 3-pin TO-92 package with leads formed to 100-mil (2.54 mm) spacing for tape-and-reel handling. Pin 1 is Ground, Pin 2 is Data (open-drain 1-Wire I/O), and Pin 3 is No Connect (NC). The device draws power parasitically from the DATA line during active communication.

Key Features

Applications

Equivalent & Alternatives

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

Compared with DS2430A+, DS2431+ offers higher EEPROM density but omits OTP locking, while DS28EC20 adds cryptographic authentication at the cost of increased protocol complexity and absence of parasitic-power-only operation.

Availability

DS2430A+ is available at Aetrix Electronics and suitable for industrial calibration storage, board-level identification, and product revision tracking requiring stable component supply and long-term obsolescence management.

Supply support for DS2430A+ 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 is a global semiconductor leader specializing in high-performance analog, mixed-signal, and digital signal processing technologies.

The DS2430A+ belongs to Analog Devices' 1-Wire memory product line, designed for low-pin-count, parasitic-powered identification and nonvolatile data storage in space-constrained industrial and embedded systems.

FAQ

What is the function of Pin 3 on the DS2430A+?

Pin 3 on the DS2430A+ is a No Connect (NC) terminal - it is internally unconnected and must remain floating or be tied to ground per layout guidelines. This pin has no electrical function in the DS2430A+ and does not affect 1-Wire communication or parasitic power operation. The DS2430A+ relies solely on Pin 1 (GND) and Pin 2 (Data) for full functionality.

Does the DS2430A+ require an external power supply?

No, the DS2430A+ operates with parasitic power only - it derives all operating energy from the 1-Wire DATA line during active communication. No external VDD connection is needed. This is confirmed by its absolute maximum rating listing "Voltage Range on DATA to Ground" and functional description stating "power to read and write the DS2430A is derived entirely from the 1-Wire communication line." The DS2430A+ remains fully compliant with this architecture in the DS2430A+ variant.

How is the application register locked on the DS2430A+?

The application register on the DS2430A+ is locked permanently using the Copy & Lock Application Register command (5Ah) followed by validation key A5h. Once executed, the two least significant bits of the 8-bit status register change from FFh to FCh, and further writes to the application register are denied. This lock is irreversible and occurs after tPROG (programming time) with the DATA line held above VPUPmin - a behavior identical across all DS2430A variants including DS2430A+.

What is the significance of the 8-bit family code 14h in the DS2430A+?

The 8-bit family code 14h identifies the DS2430A+ as a member of the 256-bit 1-Wire EEPROM family and instructs the bus controller to use specific memory function command sets (e.g., 0Fh, AAh, 55h, F0h) and timing parameters. It appears as the first byte in the 64-bit ROM and ensures protocol compatibility - readers detecting 14h will apply correct command parsing and CRC generation (X⁸ + X⁵ + X⁴ + 1) for the DS2430A+.

Can the DS2430A+ be used in multidrop 1-Wire networks?

Yes, the DS2430A+ is explicitly designed for multidrop 1-Wire networks. Its built-in multidrop controller supports Match ROM (55h) and Search ROM (F0h) commands to uniquely address individual devices on a shared bus. The datasheet confirms compatibility with other 1-Wire Net products and specifies timing margins (e.g., extended tREC for multidevice configurations) that validate robust operation in networks with multiple DS2430A+ units.