BUY DS1315S-5 https://www.utsource.net/itm/p/844715.html
Phantom Time Chip
Description: The DS1315S-5 is a real-time clock (RTC) module from Dallas Semiconductor. It is a low-power, full-function clock/calendar with an integrated oscillator and battery backup. Features: Low power CMOS technology Real-time clock/calendar 56-byte RAM Battery backup Integrated oscillator 2-wire serial interface Programmable square-wave output Automatic power-fail detect and switch 8-pin SOIC package Applications: The DS1315S-5 is suitable for a wide range of applications, including timekeeping and data logging in industrial, automotive, and consumer applications. It can also be used in embedded systems, medical equipment, and other applications requiring accurate timekeeping. (For reference only)