The basic concept of opamp-based peak detector with reset (FET)

[lego_tech]

Hi

Can anybody show me an similar example of this type of circuit?

 

[IanP]

Re: A peak detector with reset

The basic concept of opamp-based peak detector with reset (FET) can be found here:

http://www.smithshardware.com/Project/Peak_Detectors.pdf

To fulfil other requirements, you will have to add a current limiting resistor in series with the FET(reset) and re-calculate the value of the storage capacitor (that’s the 10mV/s) ..

Rgds,
IanP

 

[lego_tech]

Re: A peak detector with reset

Whats the formula to calculate the voltage across the capacitor to get 10mV?

I am coming across too many formulas at the moment & the book does not explain it very well.

 

[IanP]

Re: A peak detector with reset

Try formula for discharging RC circuit .. and solve it for C ..

t=1s
Vo=1V
V=Vo-10mV
and
R=1MΩ ..

Rgds,
IanP

PS: keep in mind that q=V*C ..