pmic STPMIC1A

[guansonghuang]

Hi st friends:

  stm32mp135f-dk bord use pmic  STPMIC1D, but it is too expensive than STPMIC1A.

can i replace STPMIC1D with STPMIC1A

[PatrickF]

Hi @guansonghuang 

in large quantities, both should be same pricing, but I agree that STPMIC1D pricing at distributor is probably higher due to more volume sold on STPMIC1A (as STPMI1D is more recent and still ramping up for larger quantities).

You could use STPMIC1A, but the board should be adapted (not a drop-in replacement on existing board using STPMIC1D).

With STPMIC1A, VDDCORE and VDDCPU are merged on Buck1. This mean no VDDCPU overdrive, so only STM32MP135C supported.

Please refer to AN5587.

 

Regards.

[guansonghuang]

  @PatrickF thank you. but I think  if  is it  ok to  add  and external LDO to convert buck4(3.3v) to 1.2v,

 

[PatrickF]

Hi,

not sure to understand the meaning of adding an LDO. Converting buck4 3.3V to 1.2V is more  expensive than simply connecting VDDCPU/VDDCORE to BUCK1 as listed in AN5587 and does not bring any gain (as Overdrive still not possible).

See also AN5586 for discrete power supply information.

Regards.