I have taken on a hobby project and I am trying to make a circuit which would be able to identify an acoustic signal with a frequency of 40kHz.
Here is the circuit of a band pass filter for this:
The issue is:
1) What would be the best way to detect the signal for the input?
2) This circuit will be mounted on a moving object and so it would be connected to a DC power supply (battery). This means that I would need a single supply op amp which has a GBW of 928k Hz but was also recommended 3.98M Hz.
I am new to this and would usually just try to figure this out myself but I cant for the life of me find an op amp of this specification?
I would appreciate any help.