BUY DS1218S https://www.utsource.net/itm/p/794130.html
Nonvolatile Controller
Description: The DS1218S is a nonvolatile static RAM (NVRAM) with an 8-pin small-outline package (SOP). Feature: Low power CMOS technology 2K x 8 bit organization Battery-backed operation Automatic write-protect on low battery Data retention for 10 years minimum Fast access time: 70 ns Application: The DS1218S is used in applications that require nonvolatile memory, such as data logging, system configuration, and parameter storage. (For reference only)