Hello,
I have a 50 KiloHertz rectified sinewave current waveform which is flowing in a 1 milliohm current sense resistor (so its really a 100KHz current waveform).
I wish to amplify only the average value of the current sense resitor voltage (x100)
Here is the schematic
Schematic
http://i46.tinypic.com/29n9qh1.jpg
Here is the current waveform
100 KHz current waveform
http://i46.tinypic.com/2vj74gj.jpg
...........I do only want to amplify the average value of the current waveform.
But ....OPA335 GBW = 2MHz so with a gain of 100, i'll have about 20kHz bandwidth, the amplifier isn't fast enough to even "see" the waveform.
...is this going to be a problem?.....will i not get an accurate amplification of the average value of the current sense resistor voltage waveform?
I put the capacitors C1 and C2 in there so that i could hopefully filter out the 100KHz.......so that i just amplify the average value, but is this the case?
.....or do i need to actually somehow filter the voltage across the current seense resistor?
I have a 50 KiloHertz rectified sinewave current waveform which is flowing in a 1 milliohm current sense resistor (so its really a 100KHz current waveform).
I wish to amplify only the average value of the current sense resitor voltage (x100)
Here is the schematic
Schematic
http://i46.tinypic.com/29n9qh1.jpg
Here is the current waveform
100 KHz current waveform
http://i46.tinypic.com/2vj74gj.jpg
...........I do only want to amplify the average value of the current waveform.
But ....OPA335 GBW = 2MHz so with a gain of 100, i'll have about 20kHz bandwidth, the amplifier isn't fast enough to even "see" the waveform.
...is this going to be a problem?.....will i not get an accurate amplification of the average value of the current sense resistor voltage waveform?
I put the capacitors C1 and C2 in there so that i could hopefully filter out the 100KHz.......so that i just amplify the average value, but is this the case?
.....or do i need to actually somehow filter the voltage across the current seense resistor?
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