Hey !!

How can I get constant DC if I have pulsating DC ?
e.g A sine wave of 5Vpp and offset of 2.5V then how can I get constant 5V which is maximum amplitude of sine wave...

 

Rectifify it with a diode and large capacitor filter. The maximum you can get with a large, low forward drop Schottky diode would be about 4.8V with a small load (a few mA or so).

 

basically I want to calculate the amplitude of sine wave using ADC of PIC16F887. But at higher frequencies, lets say 1MHz, it won't get the samples and skip peaks.
so what should be done to get these peaks ? How can I slow down the incoming frequency and get the same amplitude as the original frequency.

 

You could use a high speed peak detector circuit.

 

ok thanks. lemme check.