Need some ideas on how to develop AGC ?

[elecs_gene]

AGC

hi
can someone give me some ideas on how to develop AGC?i recently,tried one but found that it works only for a very small range.i used a FET as a variable resistor to vary the input voltage to the amplifier based on the applied input voltage. is this not a good method of designing it?any reply in this regard would be appreciable..

regards

 

[paulux]

Re: AGC

FET is a good candidate of voltage-controlled variable resistor. I guess your problem might be due to the controlled circuit. It might be helpful if you could provide the details & schematics of your circuit.

 

[artem]

AGC

there are ready to use variable gain amplifiers, e.g. from analog devices.

 

[OMEsystem]

Re: AGC

The AGC range is decided by how small the MOS resistance you can obtain.
So, you have to make sure your MOS resistor with enough W/L and hihg/low
control voltage.

Added after 59 seconds:

hi
can someone give me some ideas on how to develop AGC?i recently,tried one but found that it works only for a very small range.i used a FET as a variable resistor to vary the input voltage to the amplifier based on the applied input voltage. is this not a good method of designing it?any reply in this regard would be appreciable..

regards

BTW, What's the AGC range you need?