BUY DS1302Z+ https://www.utsource.net/itm/p/11221023.html
IC RTC CLK/CALENDAR SER 8-SOIC
Description: The DS1302Z+ is a Real-Time Clock (RTC) IC from Dallas Semiconductor. It is a low-power clock/calendar with a built-in 31-byte, battery-backed RAM. Features: * Low power consumption * 31-byte, battery-backed RAM * Clock/calendar with seconds, minutes, hours, day, date, month, and year * Leap year compensation valid up to 2100 * Programmable square-wave output * Programmable clock/calendar Applications: * Automotive * Industrial * Consumer * Medical * Wearable * IoT (For reference only)