DS1312E

Controllers Overview

The DS1312E+ is a nonvolatile RAM controller in a 20-TSSOP package. It converts CMOS SRAM into nonvolatile memory by monitoring VCCI for out-of-tolerance conditions and inhibiting chip enable to write-protect the SRAM. Upon power failure, it automatically switches to a battery backup supply with a voltage drop of less than 0.2V. The device features an open-drain reset output (RST) that activates during power failures and holds the processor in reset during system power-up. It operates within a supply voltage range of 4.75V to 5.5V and supports an industrial temperature range of -40°C to +85°C.

Controllers Feature Summary

• Converts CMOS SRAM into nonvolatile memory through automatic power switching and unconditional write protection when VCC is out of tolerance.
• Monitors lithium cell voltage and provides advanced warning of impending battery failure via an active low Battery Warning output signal.
• Includes an optional reset pin that signals impending power failure and holds the processor in reset during system power-up.

Controllers Applications

• Battery backup support for SRAM modules
• Processor-based systems requiring power-fail detection
• Lithium battery monitoring applications

Controllers Procurement Notes

Verify the component status as obsolete or end-of-life before procurement planning. Confirm the specific ordering suffix matches the required package type and RoHS compliance. Check for available replacement options from Analog Devices Inc./Maxim Integrated if current stock is unavailable. Ensure compatibility with existing PCB footprints and design specifications.

Controllers Selection Notes

Select the DS1312E+ variant specifically for designs requiring the 20-pin TSSOP package and integrated reset functionality. Consider the 5% or 10% power-fail detection options based on system tolerance requirements defined by the TOL pin configuration. Evaluate the need for processor reset capabilities during power transients to ensure system stability.

Controllers Part Context

The DS1312 series includes variants such as DS1312S+ (16-pin SOIC) and DS1312E+ (20-pin TSSOP). The E suffix denotes the 20-pin TSSOP package which includes the additional RST pin for processor reset functions. Other variants like DS1312S-2+ offer 8-pin SOIC packaging without the reset feature. All variants share core nonvolatile control and battery monitoring capabilities.

Controllers Replacement Considerations

Public confirmed substitute part numbers are not explicitly listed in the provided documentation. Verify availability of direct replacements or updated equivalents from Analog Devices Inc./Maxim Integrated due to the product's obsolete status.

Controllers FAQ

How does the DS1312E+ protect data during a power failure?

It unconditionally write-protects the SRAM by inhibiting the chip enable output (CEO) when VCCI is out of tolerance and automatically switches to the battery backup supply to maintain uninterrupted power.

What is the function of the RST pin on the DS1312E+?

The RST pin serves as an open-drain reset output that activates when VCCI falls below the trip point level defined by the TOL pin, signaling impending power failure and holding the processor in reset during system power-up.