Hi all, I’m an ME student and very new to circuitry. I designed a non-inverting op-amp on a breadboard with a LM741 that functions between a positive voltage supply and ground, no negative supply. I used Rf= 33kohm and Ri = 1kohm. I excited it with 10V and used 0.01 V as my input voltage. From a TinkerCAD simulation and design equations, I expected an output voltage around 0.3 V. I wanted a minimum gain around 30. However, in testing I had an output voltage of 8.88 V, meaning an 880 gain. Does anyone have any insight on what may have happened? Thank you!
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The 741 can’t do inputs (or outputs) near the negative supply, which in your case is 0V. Get an opamp that goes to the negative rail or use a + and – supply.
Add a 5v regulator to give you +/- 5V supply regulator will create the 0v rail.
I’m assuming you are amplifying a strain gauge or load cell. So you want to be in the linear region of operation.