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Question about this charge pump

I have some questions about this charge pump:
http://img412.imageshack.us/img412/149/chargevn1.png
This should give a gate voltage to nmos switch equal to 2Vdd, but i
don't understand how does it....If i consider an input voltage equal
to 0V,inverter gives Vdd,this voltage becames left nmos gate
voltage,this charges C1 to Vdd . So, the voltage drop in C1 is equal
to Vdd, in C2 is equal to 0.This procedure is wrong because it doesn't
give the same results in figure...so how this circuit works?
Thanks
 
M

Michael Robinson

Jan 1, 1970
0
I have some questions about this charge pump:
http://img412.imageshack.us/img412/149/chargevn1.png
This should give a gate voltage to nmos switch equal to 2Vdd, but i
don't understand how does it....If i consider an input voltage equal
to 0V,inverter gives Vdd,this voltage becames left nmos gate
voltage,this charges C1 to Vdd . So, the voltage drop in C1 is equal
to Vdd, in C2 is equal to 0.This procedure is wrong because it doesn't
give the same results in figure...so how this circuit works?
Thanks
Somebody needs to explicate that diagram.
One would assume that the mosfet pair forms a bistable multivibrator -- but
then why are the gates connected to the sources? And what are n-channel
mosfets doing at the top rail?
If this is a well-known circuit, there ought to be links to some other pages
that actually explain what's going on and have the components clearly
labeled.
 
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