Backup-Battery has a 25uA consumption when system power off

[missingno]

We know that the RTC consumes about 2uA of current.
Actually, when I disconnect the power cable form board, the battery discharge is 1.8uA.
What is unusual is that when I plug in the power supply, the system in the shutdown state, the battery discharge is actually 25uA.
When I power on the system, it will enable charging battery function by default. I try to disable the function in DTB (by delete the “backup-battery” node), the battery will also discharge 25uA when I power on the system.
I try to install jetson-nano to the carried board, battery discharges 2uA when power off.
I want to ask is this normal? What modules are consuming more current?

[Trumany]

Hi, what carrier board are you using? Is it custom board or devkit carrier? And it is compatible to both Xavier NX and nano module?

[Trumany]

In addition, ~23uA is of the low-jitter mode, ~2uA is of the low power mode.

[missingno]

Thank your reply, we’ve tested it on both boards, and it’s consistent. They are compatiable to both Xavier NX and nano module.

[missingno]

What is low-jitter mode? We try to use a non-rechargeable battery to supply RTC, if we disable the PMIC charge function, it will comsume too many current(25uA) and shorten battery life when system power off. Maybe it will work on low-jitter mode according to your discription, how should we avoid or configure it? Thank you~

[ShaneCCC]

@missingno
Please configure the PMIC max20024 register, PWR_MD_32K[1:0] of CNFG1_32K to 00 to enable low power mode.
You can try i2c utility or set it in the PMIC driver.

Thanks

[missingno]

I know xavier nx use the max77620, does it use max77620 and max20024 both for different module?
I can only find MAX77620_REG_CNFG1_32K defination in kernel source files. I can’t find the map infomation of max20024 registers. Is it same with max20024?