ST M41T94 Serial real-time clock with 44 bytes NVRAM reset handbook
Datasheet
M41T94 is a low-power clock chip produced by ST company. Its main features are 44 bytes of NVRAM and reset function, as well as 32KHz crystal oscillator, ultra-low battery supply current, automatic switching and deselection circuit, programmable alarm and interrupt function, accurate programmable watchdog timer, microprocessor power-on reset, choice of power-fail deselect voltage, etc.