how to calculate filtter capacitor value

[krishik]

hi
i want to remove the noise in the voltage across the resistor.
for that i want to add one capacitor parellel to the resistor please tell me how can i calculate capacitor valuevalue

 

[crutschow]

Adding a capacitor across the resistor will change the frequency response of the circuit so the capacitor value will depend upon your circuit and its required frequency response. What is your circuit?

 

[Jaguarjoe]

More or less, for a power supply you can use 1,000uf per amp of current.
A little closer- dV=Iload/2fC for a full wave rectifier. Use fC for half wave. C=capacitance, f=frequency, dV=ripple voltage

If that's the wrong approach, maybe you can squeeze a low pass filter in your circuit.

Trace the noise back to its source and correct it there.