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John Larkin John Larkin is offline
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Default High Side Driver - Interesting Tidbits

On Sun, 12 Jan 2014 08:35:18 -0700, Jim Thompson
wrote:

It appears the only valid data point for these power MOSFET's is the
"total gate charge", Qg. The capacitances listed are useless for
switch applications... their only value would appear to be if you were
designing an RF amplifier.

But here's the useful part...

Cgeffective = 2*Qg/Vg

This is the effective capacitance you must drive to reach your desired
Vg. (Caution, use the Qg graph, not anything in a table... Qg
increases with Vg.)

Even the schmuck-in-chief should find that useful :-}

...Jim Thompson


You said that you calculated the values in the circuit that you posted. Quit
dancing around and show us that calculation.


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John Larkin Highland Technology Inc
www.highlandtechnology.com jlarkin at highlandtechnology dot com

Precision electronic instrumentation