Hello all. I am using an STM32L496ZGT and I am getting blips of ~50mV on the VREFBUF_OUT when the reference buffer is enabled and set to 2.5V. These blips are periodic at 5Hz-6Hz.

[NVand.1]

I tried generating a file from CubeMx and leave the main empty (it is only toggling 2 GPIO pins every 500ms). The blips are still there.

The MCU is powered from a 3V3 LDO for VDD and VDDA (VDDA also has an RC filter of 0.5Ω-2.1μF in line), while the core (VDD12) is powered from an external buck at 1.2V. In the pictures below you can see the VREFBUF_OUT vs VDD, VDDA and VDD12.

Also attached is the CubeMx file used.