DS1321S+T&R

Overview

The DS1321S+T&R is a flexible nonvolatile controller with a lithium battery monitor, designed to convert CMOS SRAMs into nonvolatile memory. It operates within an industrial temperature range of -40°C to +85°C and supports a supply voltage of 4.75V to 5.5V. The device features four independent chip enable outputs for managing up to four SRAM banks in various configurations. It includes a low-leakage CMOS process for precise voltage detection and monitors backup battery capacity by periodically testing the cell under load.

Feature Summary

• Converts standard CMOS SRAMs into nonvolatile memory through automatic power switching and write protection during power failures
• Monitors lithium backup battery capacity by performing periodic loaded-voltage measurements to provide advanced warning of impending failure
• Configurable memory organization allows support for one to four SRAMs arranged in three distinct bank modes via the MODE pin

Applications

• Battery-backed data storage systems requiring seamless transition between main power and backup sources
• Industrial control applications needing processor reset signals during power outages and power-up sequences
• Embedded systems utilizing multiple SRAM chips that require centralized management and write protection

Procurement Notes

Verify the specific suffix T&R indicates reel packaging when sourcing this component. Confirm RoHS compliance status as indicated by the plus sign in the part number. Ensure compatibility with the 16-pin SO package dimensions for PCB layout. Check current availability status as manufacturing lifecycles may affect stock levels.

Selection Notes

Select this controller when designing systems that require converting volatile SRAM into nonvolatile storage without complex external circuitry. Consider the flexible memory organization options if varying numbers of SRAMs need to be managed simultaneously. Evaluate the battery monitoring requirements to determine if the periodic testing interval meets system maintenance needs.

Part Context

This component belongs to the DS1321 family of flexible nonvolatile controllers manufactured by Analog Devices Inc./Maxim Integrated. The series provides solutions for maintaining data integrity in CMOS SRAMs during power interruptions. The DS1321S variant specifically utilizes a 16-pin Small Outline package suitable for surface mount applications.

Replacement Considerations

DS1321S+