I have an MCP601 op-amp and a piezo disc and I want to amplify the signal from the piezo but also have a biased signal in order to read the negative voltages. The device is supposed to be used as a guitar tuner to pick up the vibration of a string.
Can someone explain how I would get this effect, I have read http://www.allaboutcircuits.com/textbook/semiconductors/chpt-8/op-amp-practical-considerations/ but I don't really understand it.
The following circuit is a portion of the whole thing. The rest connects to an ADC and then to a Raspberry Pi. I expected to get a bias but when it's attached the amp just amplifies the bias and I get a constant 5V.
Can anyone tell me how to alter my circuit so that I get a 2.5V bias and the piezo moves around that value?
Thank you
Can someone explain how I would get this effect, I have read http://www.allaboutcircuits.com/textbook/semiconductors/chpt-8/op-amp-practical-considerations/ but I don't really understand it.
The following circuit is a portion of the whole thing. The rest connects to an ADC and then to a Raspberry Pi. I expected to get a bias but when it's attached the amp just amplifies the bias and I get a constant 5V.
Can anyone tell me how to alter my circuit so that I get a 2.5V bias and the piezo moves around that value?
Thank you
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