Can we use coin cell battery backup for 8563t rtc?

[dhanash]

     Hi i am using 8563t rtc with rechargeable battery. Now i want to move 3V CR2032 coin cell battery,what will be the operating hours? 

[dhanash]

i need a circuit diagram for 8563T should work main power and it should work battery backup(coin cell  3V CR2032) when main power is not available.

thanks

[guoweisun]

Please download UM10301 as below link and  refer to page31 figure12.

https://www.nxp.com/docs/en/user-guide/UM10301.pdf?fsrch=1&sr=1&pageNum=1 

[dhanash]

I replaced rechargeable battery by coin cell battery (3.3V CR2032 lithium cell) then Date & Time is running. But every day 2 or 3 secs delayed. It is continuously POWER ON condition for one week. So totally 18 seconds delayed for a week. How to solve this Problem?

thank you

[dhanash]

i have 3.0V CR2032 lithium cell. In my circuit Vsup = 5.0 V, How to choose D1,D2 and R1 for proper working. waiting for your reply.  Thanks

[weidong_sun]

Hi,

For the D1/R1 you can find the related calculation method also in UM10301 page33/35.

[dhanash]

i have seen pdf and How to select Diodes (D1,D2) and R1 resistor value? while i am using primary lithium cell for backup circuit.

Thanks

[guoweisun]

Hi,

Yes,you can use coin cell battery backup PCF8563T.

Thanks!