2020-11-04 05:04 AM
I'm trying to replace the oscillator of the STM32F407 since I can't find anywhere the one listed in the bill of materials:
It's a 8Mhz crystal oscillator from jfvny and it is in a HC-49/S package, the load capacitance is 20pF and frequency tolerance of 20*10^-6, frequency stability 30*10^-6. Other than the working temperature, I can't find any other information. The capacitors and resistor in the external circuit will be reproduced like in the original schematic.
I was wondering if the LFXTAL036869Reel could be a good match, it has the same parameters mentioned before except for the frequency stability which is 20*10^-6.
I read the st guide at
and calculated its( LFXTAL036869Reel) minimal transconductance gm_crit which is 0.29 mA/V, the STM32F4 gm according to that pdf it's supposed to be 5, which makes gm>> gm_crit so I guess that gm_crit it's ok.
Does that make the oscillator a good replacement? Is there something else to look into?
2020-11-04 05:16 AM
> Is there something else to look into?
Not really. Seems like you've done your homework and verified it'll work.