From: Winfield Hill
Subject: Re: zero-power toggle circuit; was, how to master electronics
Date: 20 Nov 2002 04:09:15 -0800
Organization: Rowland Institute
References: <3DD39D90.firstname.lastname@example.org> <email@example.com> <firstname.lastname@example.org> <email@example.com>
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> Winfield Hill wrote:
>>Terry Pinnell wrote...
>>> Tony Williams wrote:
>>>> ... is it worse for P-channel MOSFETS with a higher
>>>> drain-gate capacitance?
>>> [snip ]
>>> It also looks to me as if the failures are, as you suggest, associated
>>> with higher powered MOSFETS, which have higher drain-gate capacitance.
>>> [ snip ]
>>> Anyway (despite fact that I see Win has sustained his earlier
>>> position!), I'm crystallising my original view that the circuit is
>>> very sensitive to MOSFET type.
>> Did I say you could use arbitrarily-large FETs? If so I retract it.
> That's how I understood your reply in news:firstname.lastname@example.org
> "Hey that wimpy part was Wafer's selection. You can try something
> more serious like ...
Hmm, I was rather enamored of that word, wimpy! Seems it got me into
trouble: if one uses wimpy currents (high resistor values) one must
also use wimpy FETs. Hey, I think we're onto something here. :)
>> ... reducing the resistances in proportion to any increased FET
>> capacitances would be wise. Why don't you try that in your model?
> OK, will do.
Good luck, let us know. BTW, what Spice are you using?