Placing RC snubber across source and drain of FETs on SnapAmp

[griffinboyle]

Hello, I've been struggling a lot with SnapAmp noise recently, and was wondering if placing RC snubbers across source and drain of the FETs on the SnapAmp would be a good way to stifle these switching spikes?

[TomKerekes]

Hi Griffin,

I'm not sure. The risk would be to draw large currents and reduce efficiency. The outputs are switching 80V in ~100ns. To have high efficiency these switch very fast. Unfortunately this is a source of noise. When the output is high or low there is very little power dissipation. But when switching and the output is at 40V and with 10A of current the power dissipation is 400W. But only for a small percentage of the time. The FETS can only dissipate several Watts on average. Even a small capacitor will require a large current to charge to 80V in 100ns. So snubbers should only be added with caution.