Capacitor parallel to Resistor in voltage divider Rule.....

[ss_engg]

I have a voltage divider configration and a capacitor is connected in parallel with the resistor parallel to lower resistor in voltage divider configration.... may some one tell what the purpose of this capacitor....

 

[davoud]

For more detailed discussion about your circuit , need to view of the board.
I think this capacitor designed for filtering and regulating of signal.

 

[FvM]

May be frequency compensated voltage divider, may be filter, depending on the application.

 

[ss_engg]

I have never seen about the attachment of file, so that i provide you the circuit and you guide me properly......

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For more detailed discussion about your circuit , need to view of the board.
I think this capacitor designed for filtering and regulating of signal.


well i attach a proteous file in which at pin no 4 of pic controller a capacitor be attach of 100nf parallel with 10k resistor that may be not in proteous file but present in actual circuit.. so may you please guide me the purpose of that capacitor

 

[davoud]

Unfortunately there is not file attached or there was a problem.
Please attache file again.

 

[BradtheRad]

A capacitor hooked up to the middle of a voltage divider...

This is often done at the input of an op amp, when you want to lift its level to V/2.

The capacitor is there in case it is needed to stabilize the level, although this may usually be considered optional for normal operation.

 

[ss_engg]

i would like to attach proteus file to view you the circuit in which i'm confuse why a capacitor attach in parallel ..but i have no idea how to attach that file in edaboard forum. and on which basis the value of that capacitor designed...

 

[godfreyl]

You can upload a picture of the circuit using the "Add an image" button.

 

[ss_engg]

here is the circuit diagarame... in which 100nf capacitor attach parallel with 10k resistor...
the above resistor value is 560k . please do tell the purpose of capacitor here... and how we judge that 100nf capacitor should attach there...

 

[BradtheRad]

here is the circuit diagarame... in which 100nf capacitor attach parallel with 10k resistor...
the above resistor value is 560k . please do tell the purpose of capacitor here... and how we judge that 100nf capacitor should attach there...

The resistors are in a ratio which divides the upper volt level by 56.

The high value of the upper resistor would attenuate high voltage down to a level easily handled by low voltage devices..

The capacitor might have the effect of reducing noise. Or to stabilize the volt level.

The time constant on the capacitor is calculated as RC. The bottom resistor is the chief influence by far.

Counting only that resistor the TC works out to 1/1000 second. It will attenuate high frequency AC. The 3dB dropoff is at 159 Hz.