As an introductory project to the arduino I have just built a prototype clock which on powering up takes the current time from a Sparkfun DS1307 RTC board, displays it on an LCD and then uses the 1Hz square wave from the DS1307 to periodically update the clock. So far so good and everything seems to work fine.
I now wish to transfer this to a dedicated pcb but use a PCF8563 RTC instead of the DS1307. My problem lies in understanding how to provide battery backup for the PCF8563. A quick trawl of the interwebs threw up the following circuit but the context didn't give me a great deal of confidence in it.
+5v (Vcc)
|
|
--
\/
1N4001 --
|
+3v (Batt) ----|>|--+
|
|
|--u--| |
| 8 |--|
| 5 |
| 6 |
+--| 3 |
| |-----|
| RTC
|
GND
I would be very grateful for guidance/opinions/suggestions as to whether or not this is indeed a viable solution, or if there are any others I should be considering.
