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Old 01-07-2009, 02:47 AM   #133 (permalink)
MPaulHolmes
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Some pictures of the mosfet's gate, source, drain

The picture of the rising pulse that has the little static about a third of the way up is From gate to source. The gate has some capacitance, so it takes just a moment for the gate's capacitor to fill up before the gate's voltage can rise enough to turn on the mosfet.

The picture of the dropping pulse with the little knee on it (I think it's called the miller knee, or the people's elbow. Can you smell what the rock has cooking?) is the voltage from gate to source. As the gate voltage drops, at the knee the capacitance needs to drain away so the gate voltage can drop enough to shut off the mosfet.

Another picture is from drain to source, and other stuff that I forgot now. hehe.

If there are any mistakes in the explanations above, I'm sorry. I think it's right, but I'm just learning. I'm not an engineer, Jim, I'm a doctor. I can't do it. I don't have the power.
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