Digital Clock circuit can be powered from battery for short periods of time, alternatively rechargeable battery can be used as a backup power supply in case of main power failure. Another possibility is to decrease the voltage from 5v to lower values thus reducing overall circuit power consumption. Make sure that PIC micro controller can still work at this level, in this case display current limiting resistors can be removed therefore further simplifying the design.
Digital Alarm Clock
Pages: 1 2