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-3dB Bandwidth check for active cmos RC filter

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sudeep_

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Can anyone tell me, which can be used for -3dB bandwidth check for active cmos filter using opamp like loop gain vs closed loop gain.
 

LvW

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I am not sure if I fully understand your question regarding "loop gain vs closed loop gain".
Are you speaking of a 2nd order active lowpass ?
 

sudeep_

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The circuit is designed as 2nd order Multiple feedback active cmos filter, I am not sure to check -3dB BW by considering Loop gain or Closed loop gain plot.
 

LvW

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I am not sure to check -3dB BW by considering Loop gain or Closed loop gain plot.
The filter circuit is realized using feedback. Hence, I see no reason to measure/calculate/simulate the 3dB BW not in this closed-loop configuration.
 

sudeep_

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Could you elobarate this statement. "Hence, I see no reason to measure/calculate/simulate the 3dB BW not in this closed-loop configuration".
 

LvW

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Could you elobarate this statement. "Hence, I see no reason to measure/calculate/simulate the 3dB BW not in this closed-loop configuration".
At first, can YOU elaborate the term"check"? Does it mean calculation, simulation or measurement?
 

sudeep_

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-3dB BW measurement for LPF. Which one is used for -3dB BW ( CL or loopgain plot)?


At first, can YOU elaborate the term"check"? Does it mean calculation, simulation or measurement?
 

LvW

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-3dB BW measurement for LPF. Which one is used for -3dB BW ( CL or loopgain plot)?
As I have mentioned already, the filtering action is caused by a feedback effect - hence, you measure the closed-loop response.
 

schmitt trigger

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The filter's response, regardless of type, can be obtained three ways:
1) By mathematical analysis
2) By simulation using a sweep
3) By actual hardware testing using a sinewave oscillator and a scope

Is that what you are asking? Because your question is not clear.
 
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