cancel
Showing results for 
Search instead for 
Did you mean: 

STM32H725REV and SMPS

DNA-)
Associate III

Hi,

I wanted to use the STM32H725REV without the SMPS.

The AN5419 explain that we can do it like the pic under.

But, the main problem is that, on VFQFPN Package, there is no VDDLDO pin.

The AN5419 mentions:

"On STM32H723/733, VDDLDO is not available on a pin/ball. It is internally connected to VDD"

Is that the same thing on the STM32H725REV ? Or does that it means that we can't supply the STM32 in 'LDO Supply' mode?

I've designed my board following 'LDO Supply' and i can't program.

There is 0V on Vcap pins.

0693W00000JOt7aQAD.png

2 REPLIES 2
TDK
Guru

> Is that the same thing on the STM32H725REV ?

Yes, if there is no VDDLDO pin, it is tied to VDD internally (barring an error in the datasheet). There was a thread about this with an ST response, but I can't find it now.

If you have 0V on VCAP on a brand new chip, there's another hardware issue. Verify part orientation, power rails, soldering to power rails.

If you feel a post has answered your question, please click "Accept as Solution".
DNA-)
Associate III

Hi,

Thank you for your answer. Indeed, i had this on mind but can't find any direct answer from ST.

By the way, my schématic is like attachment.

My 3V3 is good and VDDA is ok too.

I checked the pinout of the microcontroller (assignment of the pin numbers with the name of the signals) on schematic and layout, but no anomalies encountered.

I really don't understand why i have 0V on Vcap pins...

Any ideas?