Analog Devices Inc./Maxim Integrated DS2065W-100#

Overview

DS2065W-100# from Maxim Integrated is a 8Mb (1024k × 8) reflowable nonvolatile SRAM with integrated rechargeable manganese lithium (ML) battery, internal NV controller, and power-supply monitor output RST. It operates at 3.3V ±0.3V, delivers 100ns access time, and provides unconditional write-protection during VCC failure - used in RAID systems, industrial controllers, and fire alarm backup memory.

For engineers reviewing the DS2065W-100# datasheet, DS2065W-100# pinout, DS2065W-100# application, or DS2065W-100# equivalent, key selection criteria include data retention time per charge (2–3 years), open-drain RST supervisor functionality, BGA-256 package compatibility, and industrial temperature range (-40°C to +85°C).

Technical Context

The DS2065W-100# integrates SRAM, ML battery, and NV controller on a single 27mm² BGA substrate, enabling full reflow soldering without battery removal. Its power-switching circuit automatically transitions between VCC and battery supply when VCC crosses VSW (~2.5V), while write-protection activates unconditionally below VTP (2.8–3.0V).

It features an open-drain RST output with 10mA sink capability, triggered when VCC falls below VTP and held active until VCC exceeds VTP for ≥225ms (tRPU). The device supports standard asynchronous SRAM timing: CE/OE-controlled read, CE/WE-controlled write, and no external support circuitry required for microprocessor interfacing.

Key Specifications

Pinout & Package

DS2065W-100# uses a 256-ball PBGA module (27mm²) with 1.0mm ball pitch. All balls are arranged in a 16×16 grid; ground planes occupy corners and edges for noise immunity and thermal dissipation. No lead-free exemption applies - # suffix confirms RoHS compliance with lead exemptions per EU directive.

Key Features

Applications

Equivalent & Alternatives

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

Compared with DS1265W-100+ and STK15C88-3LF1, DS2065W-100# uniquely combines 8Mb capacity, 100ns speed, reflowable ML battery, UL recognition, and integrated RST - making it the only drop-in solution for new industrial and safety-critical designs requiring zero-battery-handling overhead and guaranteed data retention.

Availability

DS2065W-100# is available at Aetrix Electronics and suitable for RAID systems, industrial controllers, and fire alarm panels requiring stable component supply, long-life data retention, and RoHS-compliant reflow assembly.

Supply support for DS2065W-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

Maxim Integrated (now part of Analog Devices) designs precision analog, mixed-signal, and power management ICs for industrial, automotive, and communications applications.

The DS2065W-100# belongs to Maxim's nonvolatile SRAM product line, engineered specifically for mission-critical memory backup where reliability, reflow compatibility, and integrated supervision are mandatory.

FAQ

What is the guaranteed data retention time for DS2065W-100# under normal conditions?

The DS2065W-100# provides 2–3 years of data retention per full charge at +25°C, based on component selection, process control, and design validation. This assumes initial 96-hour charge at VCC > VTP and no more than two +230°C reflow exposures. Retention is measured from first VCC application and degrades predictably with temperature and discharge depth.

Does DS2065W-100# require external components to function as a nonvolatile SRAM?

No, DS2065W-100# requires no external components for core NV operation: the internal ML battery, charger, power switch, and write-protection logic are fully integrated. Only a 0.1µF ceramic decoupling capacitor on VCC and a pullup resistor (1kΩ–10kΩ) on RST are recommended for optimal performance and reset signaling.

How does the RST output of DS2065W-100# behave during power-up and power-down?

During power-down, RST asserts low within 3.0µs (tRPD) after VCC falls below VTP and remains low until VCC drops below battery voltage. During power-up, RST stays low until VCC exceeds VTP and remains low for 225–525ms (tRPU) to ensure SRAM readiness - longer than tREC (125ms) to guarantee safe CPU access.

Can DS2065W-100# be used as a direct replacement for standard 100ns SRAMs?

Yes, DS2065W-100# is pin- and timing-compatible with standard 100ns 1024k × 8 SRAMs: identical address/data/control pinout, same CE/OE/WE timing windows (tRC = tACC = 100ns), and TTL-compatible logic levels. Its NV functionality activates transparently during power loss without altering host interface behavior.

What is the maximum battery charge time required for DS2065W-100# after initial power application?

DS2065W-100# requires up to 96 hours of continuous VCC application (>VTP) to achieve full ML battery charge from a depleted state. As shipped, the battery is ~60% charged; no preassembly charging is needed, but full 96-hour conditioning is recommended for new system installations to maximize retention duration.