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LMV794: Not getting the correct gain.

Part Number: LMV794
Other Parts Discussed in Thread: OPA365

Hello,

I am using LMV794 as BPF to filter out the downconverted signal from 18.72Mhz to 32KHz signal. I am using a switch prior to this BPF filter, and I wasn't getting a intended gain, so I separated the switch, and I fed in function generator to debug the BPF filter only.

The schematic attached is a band pass filter that has a center frequency at 32700Hz. I am feeding in at the input with 32KHz signal, and I am getting the gain of 1~1.5 when the intended gain is 4.13. The Quality factor of filter is 20, and all of the components I am using for this schematic is under 1% tolerance level. I am using dual channel with exactly same component, but I am getting different gain in two different channel as well. Do you think that my quality factor is too high? I also read from the spec sheet saying that this opamp has to have a minimum gain of 10, and I am pretty confused if my opamp is also oscillating as well. Do you think that having 1.6nF loading capacitor is too high? should I lower the quality factor? I have been stuck at this for a few weeks, and any input would be greatly appreciated.

Thank you so much

Young