Analog Devices Inc./Maxim Integrated DS1250Y-70+

Overview

DS1250Y-70+ from Maxim Integrated is a 4,194,304-bit (512k × 8) nonvolatile static RAM with integrated lithium backup, JEDEC-standard 32-pin DIP package, 70 ns access time, ±10% V_CC tolerance (4.5 V to 5.5 V), and 10-year data retention without external power - used in industrial control systems requiring persistent memory during brownouts.

For engineers reviewing the DS1250Y-70+ datasheet, DS1250Y-70+ pinout, DS1250Y-70+ application, or DS1250Y-70+ equivalent, this page delivers verified timing behavior, write-protection thresholds, battery-enable sequencing, and direct replacement guidance for legacy 512k×8 SRAM sockets.

Technical Context

The DS1250Y-70+ integrates SRAM, lithium battery, and voltage-monitoring circuitry into a single monolithic DIP package. It autonomously switches to battery backup when V_CC falls below 4.25 V (write-protect threshold) and disconnects the lithium source until first power-up to preserve capacity.

It operates as a byte-wide parallel memory with full static interface compatibility: CE/WE/OE control logic, no external support circuitry required, and deterministic read/write timing governed by t_ACC = 70 ns, t_WC = 70 ns, and t_OE = 35 ns under V_CC = 5 V ±10%.

Key Specifications

Pinout & Package

DS1250Y-70+ uses a JEDEC-standard 32-pin extended DIP (740-mil width) with solder-through leads. The package integrates SRAM, lithium battery, and power-fail detection circuitry in one hermetically sealed unit.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar nonvolatile SRAM applications.

Compared with DS1250AB-70+, the DS1250Y-70+ offers wider supply tolerance and earlier write protection - critical for unregulated industrial rails; versus STK12C68-70I, it eliminates external backup components and guarantees 10-year retention without capacitor aging concerns.

Availability

DS1250Y-70+ is available at Aetrix Electronics and suitable for industrial control systems, smart metering platforms, and medical device configuration storage requiring stable component supply with guaranteed 10-year data retention and commercial-temperature reliability.

Supply support for DS1250Y-70+ 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

Maxim Integrated (now part of Analog Devices) designs precision analog, mixed-signal, and nonvolatile memory solutions for industrial, automotive, and communications markets.

The DS1250Y-70+ belongs to Maxim's nonvolatile SRAM product line, engineered to replace volatile memory in systems where data persistence during power loss is mission-critical - especially in infrastructure and safety-related equipment.

FAQ

What is the guaranteed data retention period for the DS1250Y-70+?

The DS1250Y-70+ guarantees a minimum 10-year data retention period in the absence of external power, measured from the time V_CC is first applied. This is assured through component selection, process control, and integrated lithium cell design - not extrapolated or estimated. The DS1250Y-70+ achieves this by automatically switching to battery backup when V_CC drops below ~3.0 V and maintaining SRAM state without refresh.

Does the DS1250Y-70+ require external components for nonvolatile operation?

No, the DS1250Y-70+ requires no external capacitors, diodes, regulators, or control ICs for nonvolatile operation. Its integrated lithium energy source and voltage-monitoring circuitry are fully self-contained within the 32-pin DIP package. The DS1250Y-70+ activates its battery only during power loss and remains disconnected until first V_CC application - eliminating design overhead and failure points.

How does the DS1250Y-70+ handle power-down and power-up transitions?

During power-down, the DS1250Y-70+ detects V_CC decay within 1.5 µs, disables writes at 4.25 V, and connects the lithium source when V_CC falls to ~3.0 V. On power-up, it disconnects the battery and resumes normal operation once V_CC exceeds 4.5 V. The DS1250Y-70+ enforces t_REC = 125 ms recovery before accepting new commands to ensure stable initialization.

Is the DS1250Y-70+ pin-compatible with standard 512k×8 SRAMs?

Yes, the DS1250Y-70+ uses a JEDEC-standard 32-pin DIP footprint with identical pinout to industry-standard 512k×8 volatile SRAMs - including A0–A18, DQ0–DQ7, CE, WE, OE, V_CC, and GND. Pins 1 and 32 are NC and match typical socket layouts. No PCB modification is needed for drop-in replacement of legacy SRAMs in existing designs.

What is the write-protection voltage threshold for the DS1250Y-70+?

The DS1250Y-70+ asserts unconditional write protection when V_CC falls below 4.25 V (minimum), with typical threshold at 4.37 V and maximum at 4.50 V. This threshold is factory-trimmed and tested - it is not adjustable. Once triggered, all inputs become "don't care" and outputs go high-impedance, preventing partial writes or corruption during marginal supply conditions. The DS1250Y-70+ maintains this behavior across its full 0°C to +70°C operating range.