Maxim DS1321S+

非易失性 RAM4.75V ~ 5.5V-40°C ~ 85°C

Overview

The DS1321S Flexible Nonvolatile Controller with Lithium Battery Monitor is a CMOS circuit which solves the application problem of converting CMOS SRAMs into nonvolatile memory. Incoming power is monitored for an out-of-tolerance condition. When such a condition is detected, chip enable outputs are inhibited to accomplish write protection and the battery is switched on to supply the SRAMs with uninterrupted power. Special circuitry uses a low-leakage CMOS process which affords precise voltage detection at extremely low battery consumption. One DS1321S can support as many as four SRAMs arranged in any of three memory configurations. In addition to battery-backup support, the DS1321S performs the important function of monitoring the remaining capacity of the lithium battery and providing a warning before the battery reaches end-of-life. Because the open-circuit voltage of a lithium backup battery remains relatively constant over the majority of its life, accurate battery monitoring requires loaded-battery voltage measurement. The DS1321S performs such measurement by periodically comparing the voltage of the battery as it supports an internal resistive load with a carefully selected reference voltage. If the battery voltage falls below the reference voltage under such conditions, the battery will soon reach end-of-life. As a result, the Battery Warning pin is activated to signal the need for battery replacement.

Features

Tube Package
Available in the 16-SOIC (0.154, 3.90mm Width) package
Nonvolatile RAM as controller type
Operating temperature of -40°C~85°C
Operating supply current of 50μA
Operating supply voltage of 5V

Surface Mount Mounting Type

Applications

There are a lot of Maxim Integrated
DS1321S+ Memory Controllers applications.

• Point-of-Sale Systems
• Facsimile, Printers and Photocopiers
• Internet Appliances
• Servers
• Medical Instrumentation and Industrial Products
• Industrial USB Flash Drive
• eUSB, embedded USB module
• Ultra durable Flash Drive
• Security Flash Drive
• Multi-Chip-Package (MCP)