Core supply for STM32H573MIY3Q

[MarwinS]

Hello,

we have to use the STM32H573 in the 80 Pin WLCSP with temperature Range 3 (to 125°C). So STM32H573MIY3Q was chosen. Due to a mistake we didn't recognized that the internal LDO can't be used. Now we have no space for placing additional components as the inductor to use the SMPS. The STM is on a tiny board which is connected on a baseboard on this is more space for components.

So now we have two options:

1.  Use an external LDO on the tiny board, we have 1,8V spare to burn down. How much current shall we consider (250 MHz). The maximum IDD ist stated with 125,2 mA, does any additional current has to be added?
2. Use an external DCDC on the baseboard.

In both cases the Questions are:

How has the pins of SMPS to be configured (by hardware) to shut down the SMPS appropriately?
Do we have to use the VCAP as an input?

If STM staff is reading this please get in touch with us immediately. Thanks.

So long
Marwin

Edits: Some minor spellings

[TDK]

> Due to a mistake we didn't recognized that the internal LDO can't be used.

??  You're not required to use SMPS.

See "Figure 6. STM32H523/H533/H562/H563/H573 power-supply scheme with LDO" in the following document:

Getting started with STM32H5 MCU hardware development - Application note

> The maximum IDD ist stated with 125,2 mA, does any additional current has to be added?

Is there other stuff on the board that will be taking current? Do you want any margin? If not, just plan for 125 mA.