DS1212

Controllers Overview

The DS1212 is a nonvolatile controller IC designed to convert CMOS RAMs into nonvolatile memories. It operates with a supply voltage range of 4.75V to 5.5V and features a 4-to-16 decoder for controlling up to 16 CMOS RAMs. The device monitors incoming power, inhibiting chip enables during out-of-tolerance conditions to provide write protection. It automatically switches to battery backup upon power failure, consuming less than 100 nA of battery current. The component supports redundant batteries and includes a power-fail signal for processor interruption.

Controllers Feature Summary

• Converts full CMOS RAM into nonvolatile memory
• Unconditionally write protects when VCC is out of tolerance
• Automatically switches to battery when power-fail occurs
• Tests battery condition on power-up

Controllers Applications

• Battery-backed memory systems
• Data storage requiring power-fail protection
• Embedded systems needing nonvolatile RAM conversion

Controllers Procurement Notes

Verify the specific suffix (e.g., N, +) against the required operating temperature range, as commercial and industrial variants exist. Confirm package type availability, noting that surface mount PLCC options are also offered alongside the standard DIP. Check manufacturer documentation for obsolescence status, as this component has been subject to discontinuation notices.

Controllers Selection Notes

Select based on the required number of RAM chips, as the decoder supports up to 16 units. Consider the TOL pin configuration to adjust power-fail detection thresholds between 4.75V/4.5V or 4.5V/4.25V ranges. Ensure the application environment matches the specified operating temperature grade. Verify battery input requirements, including the option for redundant battery connections.

Controllers Part Context

The DS1212 belongs to the Dallas Semiconductor/Maxim Integrated family of nonvolatile controllers. It addresses the challenge of maintaining data integrity in volatile RAM circuits during power interruptions. By integrating decoding, switching, and monitoring functions, it simplifies the design of reliable nonvolatile memory subsystems compared to discrete solutions.

Controllers Replacement Considerations

DS1213: SmartSocket SRAM controller with similar interface but different architecture.