BUY DS1667-010 https://www.utsource.net/itm/p/1747589.html
Digital Resistor with OP AMP
The DS1667-010 is a Nonvolatile SRAM manufactured by Dallas Semiconductor. It is a 20-pin DIP package and is a low-power, low-voltage device. It is a 256 x 8-bit nonvolatile static RAM with a built-in lithium battery. The DS1667-010 is designed to provide a reliable, low-power memory solution for applications that require data retention in the event of a power failure. It is ideal for applications such as data logging, security systems, and remote control systems. Features: 256 x 8-bit nonvolatile static RAM Low-power, low-voltage operation Built-in lithium battery Data retention in the event of a power failure Fast access time 20-pin DIP package Applications: Data logging Security systems Remote control systems (For reference only)