Understanding VFBSMPS Function

vasyl

What is VFBSMPS used for?

7 days

flux

1:01

Analyzing the schematic.

Looking for "What is the function of pin VFBSMPS on STM32WLE5JCI6? Include what it connects to or is used for in the SMPS/internal regulator circuitry and any recommended connection guidance." in stm32wle5j8.pdf

Clarifying component details.

Defining VFBSMPS details.

Considering external components.

VFBSMPS is the SMPS feedback / 1.55 V regulator node for this device.

In your part project, it is terminal B2.
Per the datasheet, this pin is the external supply node for the main system regulator, typically around 1.55 V.
It is used when the chip’s internal SMPS step-down converter is enabled, as part of the power path that generates the internal core/regulator supply.
If the SMPS option is not used, the datasheet notes the external SMPS coil between the switching node and this feedback/output node can be omitted.

So, practically: VFBSMPS is not a general GPIO or signal pin - it is a power-management pin associated with the MCU’s SMPS/regulator circuitry.

If you want, I can also identify the exact recommended external connections for VFBSMPS, VLXSMPS, and the related supply pins from the datasheet.

Show connected parts

Check feedback divider

Review SMPS feedback

7 days

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