The RV-3049-C3-TB-QA-OPT.A is an ultra-miniature Real-Time-Clock Module with embedded crystal. This RTC has an SPI bus (4-wire serial interface) and offers temperature compensated time. Beside standard RTC functions, it includes a backup-battery Input with internal switchover function, a programmable trickle-charge circuitry, an integrated temperature sensor with digital-output and offers 8-bytes RAM and 2-bytes EEPROM for customers application. The calendar function tracks year and leap-year flags. The clock tracks second, minute and hour in 24-hour format. Programmable alarm setting and universal timer functions increase flexibility.