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John Larkin John Larkin is offline
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Default Small MOSFET input capacitance.

On Wed, 1 Sep 2010 15:00:35 +0100, "ian field"
wrote:

Does a source follower present lower apparent input capacitance?

I'm thinking in terms of 2N7000/BS170 sized devices.

Thanks.


Yes. If the follower voltage gain is close to 1, the gate-source
capacitance is bootstrapped and goes away. All that's left is
drain-gate capacitance. You can bootstrap that, too, with another
follower.

John