Power leak when DA9053 RTC is enabled?

frankchenmh · ‎09-12-2013

On our MX53 board (it is based on MX53 SMD) we have a cell battery which provides power to DA9053. When the DA9053 RTC is enabled, the date can be saved after the board is powered off. But after one or two days (or even less) the date lost and the cell battery has low power. It seems DA9053 consumes much power in power off mode so that the cell battery runs into empty quickly? Is this a known issue of DA9053? Besides RTC, which modues inside DA9053 consume power too in power off mode?

We have charged the cell battery before the test, so it should not be a cell battery issue. We tested with both Android/Linux. Thanks.

art · ‎09-19-2013

Please note that, besides driving the RTC core and other internal logic of the DA9053 PMIC when the main power is off, the backup cell battery can also drive an external load through the VDDCORE and VDDREF outputs, that can increase the load current and shorten the cell battery discharge time. So, please check carefully what external load is connected to these pins on your custom board. Also, please check the DA9053 configuration. For more information, please refer to the DA9053 documentation.

frankchenmh · ‎09-24-2013

Thanks for the reply. Is there any DA9053 programming guide for the case that only RTC consumes power when the board is powered by cell battery? I checked the DA9053 datasheet with VDDCORE and VDDREF but it looks complicated and hard to debug (hard to measure the current)...

ianhorsburgh · ‎01-20-2016

Hi Frank,

Did you manage to resolve this issue? We are having a similar problem on our board. Was this an issue with the DA9053 or with your own board?

Cheers,

Ian.

frankchenmh · ‎01-20-2016

Hi Ian,

I didn’t resolve it. I believe this is DA9053 issue and it is hard for me to find out the cause.

However we workaround the RTC issue by using other standalone RTC chip. We changed our board to achieve this.

Hope this is useful for you.

Regards,