DALLAS Fu** RTC module

This module is a drop-in replacement for old sealed-body RTC modules, commonly found on vintage computer [286,386,486 and Pentium motherboards). Over time, the internal battery in these modules dies, causing BIOS settings to be lost and preventing proper booting. The module offers a replaceable CR2032 battery socket and is compatible with several RTC chips, including the BQ3285.

BQ3285-Compatible RTC Modules

The following RTC chips are compatible with the module when using the BQ3285:

Dallas DS1287 / DS12887 / DS128B87

Benchmarq BQ3287

ODIN OEC12C887

Notes Specific to BQ3285

Equivalent ICs

Benchmarq BQ3285 ≈ Dallas DS12885

Pin Cutting Instructions

If you're using the BQ3285, you must remove the following pins on the module:

Pin 2

Pin 3

Pin 16

Pin 20

Pin 21

Pin 22

⚠️ Important: Some motherboards use pin 21 (/RCL).

Only cut it if you're sure your board does not require it.