Are VREFINT and VREFBUF output the same on STM32G4?

[abhijith_raj]

Moved from this post .

Hi @mƎALLEm ,
Is VREFINT and VREFBUF output same?
In documents I have seen VREFBUF can be set as 2.048, 2.5, 2.9, is that same VREFINT?

[waclawek.jan]

> Is VREFINT and VREFBUF output same?

No.
> In documents I have seen VREFBUF can be set as 2.048, 2.5, 2.9, is that same VREFINT?

No.

JW

[abhijith_raj]

Hi @waclawek.jan,
Could you please mention the purpose of that VREFBUF and VREFINT?

[waclawek.jan]

VREFINT is a fixed nominally 1.2V internal reference, which you can measure using the ADC, and thus indirectly establish voltage of the ADC's reference (ADC reference is always the VREF+ pin). Read the Monitoring the internal voltage reference subchapter of ADC chapter in RM0440.

VREFBUF is a voltage source with selectable voltage, which can internally be connected to VREF+ pin (but if you want to do that, you must not connect an external source to VREF+, but you must connect a prescribed capacitor to VREF+ - see datasheet). Read the Voltage reference buffer (VREFBUF) chapter in RM0440.

JW