M
MRW
- Jan 1, 1970
- 0
Hello!
Happy 4th of July to my American colleagues!
I have this circuit: http://bayimg.com/NaDlBAAbD
How does it work?
I initially thought that the first opamp is a microphone pre-amplifier
in an inverting configuration and the second one is used to invert the
signal back. But when I looked at it again, the second opamp is
configured as a voltage follower. Why is that?
I think that C6 and C7 are just used as a bypass capacitor for any
noise coming from VCC. R20 and C5 are just high pass filters that will
roll off any signal below 8Hz. R15 and R17 are used to biased the
input at half of VCC for single supply operation.
Is that the right assumption?
I also have a feeling that if the first opamp is indeed a pre-amp,
then it's gain is frequency dependent. But how do I find out the
equation for it? Is it just (-R13)/(reactance of C5) ?
Any other insights into this circuit?
Thanks!
Happy 4th of July to my American colleagues!
I have this circuit: http://bayimg.com/NaDlBAAbD
How does it work?
I initially thought that the first opamp is a microphone pre-amplifier
in an inverting configuration and the second one is used to invert the
signal back. But when I looked at it again, the second opamp is
configured as a voltage follower. Why is that?
I think that C6 and C7 are just used as a bypass capacitor for any
noise coming from VCC. R20 and C5 are just high pass filters that will
roll off any signal below 8Hz. R15 and R17 are used to biased the
input at half of VCC for single supply operation.
Is that the right assumption?
I also have a feeling that if the first opamp is indeed a pre-amp,
then it's gain is frequency dependent. But how do I find out the
equation for it? Is it just (-R13)/(reactance of C5) ?
Any other insights into this circuit?
Thanks!