Operate SDMMC1 at higher clock in LP Run mode

[dhaval]

Posted on May 16, 2016 at 08:53

Hi,

I am using STM32L4x6 MCU. I am trying to reduce the overall power consumption. For that I am running MCU @ 2MHz in LP Run mode.

Currently the SDMMC1 transfer clock is set to 800KHz. But I want to increase while keeping MCU in LP Run mode. When I am trying to increase it to even 1MHz, the SD card stops working. So is it possible to increase the clock for SDMMC1?

Thanks,

Dhaval

#stm32l4 #sdmmc1 #lp-run

[dhaval]

Posted on May 18, 2016 at 09:09

Can someone please help me here?

[Tesla DeLorean]

Posted on May 19, 2016 at 01:10

The pool of respondents here is pretty shallow.

You'll need to look over the clock tree in the reference manual, and understand from there what your options are. You will likely need to make sure not to create a clock inversion, ie where clocks slow down in the wrong direction, or where specific clocks need to be X  or 1/X times faster than the bus they are attached too.

[dhaval]

Posted on May 19, 2016 at 14:24

Thanks Clive. I will check it accordingly.