Not able to make STM32H745i Disco board running after a modification from SMPS to LDO

mridul_xalten · ‎2025-02-04

New question from this thread.

So in order to use both SMPS and LDO, given in board schematics,
I mounted SB6 and SB17 (SB44, SB46, L4 already mounted)
and removed SB5 and SB18 (rest already not mounted).

After than i flashed it with keeping the following settings.

Im still getting the same error.

LCE · ‎2025-02-04

> So basically the HW is configured in SMPS.
> So in order to obtain 480MHz, what changes should i do to the hardware.
> Or is there any way i could do it without changing the hardware?

I think the SMPS is there exactly for using the maximum CPU speed of 480 MHz, because usually at fmax the power consumption is the highest, and the SMPS should have lower loss and thus heat generation than the internal LDO.

So my guess: after using the LDO the MCU is getting warmer than with SMPS.

SofLit · ‎2025-02-04

Check the VCORE voltage.

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SofLit · ‎2025-02-04

@LCE wrote:

I think the SMPS is there exactly for using the maximum CPU speed of 480 MHz,

No. SMPS is not available in VOS0 (maximum 480Mhz). See this thread.

To give better visibility on the answered topics, please click on "Accept as Solution" on the reply which solved your issue or answered your question.
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2 - Please be polite in your reply. Otherwise, it will be reported as inappropriate and you will be permanently blacklisted from my help.