Choosing capacitance for peak detector

bertus

Joined Apr 5, 2008
20,189
Hello,

the value of the capacitor for the dector depends on the speed versus the accuracy.
A small capacitor will make it fast, but leakage will let the voltage drop.
A large capacitor will make it slow, but it will keep the maximum value much longer.

Bertus
 

Thread Starter

anhnha

Joined Apr 19, 2012
880
Thanks for the answer!
I think time constant RC is what relating to speed and accuracy here?
With RC is small, it will charge and discharge fast.
Is there a detailed treatment of this? I tried to search but couldn't find a good one.
 

Thread Starter

anhnha

Joined Apr 19, 2012
880
Actually, I am using the structure (peak detector) as a rectifier. So, I think there should be a balance here.
 

MikeML

Joined Oct 2, 2009
5,444
The simplistic peak detector shown in chapt 3 is missing a crucial element, which is a discharge path for the capacitor. The effect of the discharge path (load) must be factored into the charging time, as well as the discharging time...

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