Power ManagementのトピックRe: PCA9451A / imx93 battery backup for RTC

PCA9451A / imx93 battery backup for RTC

arekkaras — Mon, 15 Apr 2024 19:10:49 GMT

Hello,

does the PCA9451A support battery backup for NVCC_BBSM_1V8 voltage domain ?

Is there any application note/recommendation how to keep RTC running on iMX93 while there is no external 5V power supply connected to PMIC?

Regards
Arkadiusz

guoweisun — Tue, 16 Apr 2024 06:35:30 GMT

Do you mean that use battery as input of LDO1 to get the backup power?

arekkaras — Tue, 16 Apr 2024 20:16:24 GMT

Hi Guoweisun,

It was my first idea, but I realised that from this input also other LDO's are powered so it doesn't seem to be best solution.

Additionally, I am using 32kHZ RTC clock from PMIC for iMX93 as well, so in order to get this clock running IMHO whole PMIC needs to be powered ?

Regards

Arkadiusz

guoweisun — Wed, 17 Apr 2024 00:13:25 GMT

Yes，correct！