I am developing an application containing a GNSS module where the noise level in the power supply is a critical factor for the performance of the application. So much so that the GNSS module has a power system and an exclusive LDO.
I would like to read the noise level of the GNSS module power supply but there are some problems:
-> The noise level is generally less than 50mVpp. To accurately read such small voltages, you would need a very accurate reference onto the microcontroller's ADC (VDDA). What types of filters can I use? Is RC filter a good idea?
- Noise components sometimes last a few hundred nanoseconds. How can I get precision in a measurement with such a small sample?
GNSS module: NEO-M9N Microcontroller: STM32F072
Another option would be some circuit that would only indicate me when I pass 50mVpp. But it has to be something fast enough to "capture" peaks of a few hundred nanoseconds.
Could anyone give any circuit tips or help on how to achieve this goal?
Note: I want to read the noise of the GNSS module. It is a separate power supply from the microcontroller.
Thank you so much