MEMS Oscillator Reference Schematic

[Nico3]

Hello Friends, 

I have selected STM32F401XE series for my new project. The device is expected to face road vibrations and shocks, so to make system more reliable I am thinking to use MEMS oscillator rather than standard Quartz Crystal. 

I tried to search any reference schematic of STM32 MCU having MEMS osciilator but couldn’t find. 

Please share if any information available on how to use MEMS Oscillator.  

I understand  OSC-IN should be connected to OUT of MEMS Oscillator and OSC-OUT should be set to high -Z.   What about VDD of MEMS Oscillator?  Should it be set to same VDD as set in STM32F401XE MCU, which is 3.3V

 

Thanks

[mƎALLEm]

Hello,

What about VDD of MEMS Oscillator?  Should it be set to same VDD as set in STM32F401XE MCU, which is 3.3V

 

Yes if it has the same power supply level as the MCU. Need to check the mems datasheet.

What prevents you to do so?

[Nico3]

Hello, I think i didn’t write earlier clearly.

1. The STM32F401 manual says 

   

   but when I measured waveform at quartz crystal mounted on STM32F407 board , The waveform is from 2.3V to 1.2V  with frequency at 8 Mhz with VDD at 3.3V.  so I am having doubt on clock level voltage inputs required when using MEMS oscillator.

[mƎALLEm]

You said you’ve measured that waveform on the oscillator mounted with STM32F407 board.

So it’s working or not?

Is there a solder bridge between the oscillator output and the OSCI_IN of the MCU? in that case remove the solder bridge and check the voltage level and check with the oscillator datasheet.