Time is not update when reboot the board

[vinothkumars]

Hi All,

I am using PCF8523 RTC Chip and also I mounted Coin Cell also. I configured Coin Cell as Standard mode and low Detection Mode (000). But, after setting the time when rebooting the time is not update.

Reference,

https://www.nxp.com/docs/en/data-sheet/PCF8523.pdf 

If anyone know how to make this coin cell work when power off the board, As per datasheet I initialize control register 3 = 000. But, I not getting the time when power on the board

And we are using 3V battery and I want to know how much Voltage we got when switch OFF the board and switch ON the board?

[guoweisun]

Do you mind provide your schematic?

[vinothkumars]

Hi when we check the battery the voltage we got in both on and off state is 0.4 volt only. 

[guoweisun]

Hi,

Do you have a discharge loop circuit of battery in your system?

Can you try to change a new battery to test?

[vinothkumars]

Thank you for your reply ,

I will replace and try whatever you suggest

[vinothkumars]

Please check previous replayed one, i attached screenshot of schematic of pcf8523

[guoweisun]

Hi

What's your system power voltage of RTC and your coin cell voltage?

Thanks!

[vinothkumars]

Thank you for your reply,

Vdd is 3.3volt and vbad is 3.3 volt