| RTC counts seconds, minutes, hours, date of the month, month, day of the week, and year with leap-year compensation valid up to 2100 56-byte battery-backed NV RAM for data storage 2-wire serial interface Programmable square-wave output signal Automatic power-fail detect and switch circuitry Consumes less than 500nA in battery-backup mode with oscillator running Recognized by Underwriters Laboratory (UL) |