Hi,
I'm trying to make an amplifying circuit and I'm sort of without a clue on what OpAmp to use.
I'm amplifying the result from one half-bridge from a Wheatstone bridge. The input is 5V so the output should be 2.5V + the signal I want to amplify.
In a first step I want to cancel the 2.5V by putting the 2.5V+Signal into the non-inverting input of the OpAmp and I put 5V in the inverting end with a large resistance between the 5V and the Opamp as well as a large resistance between the OpAmp inverting Input and the Output. This should let just the signal pass. (basically an inverting amplifier with the ground at 2.5V+Signal)
Then I want to amplify that signal with a standard non-inverting amplifier. The signal can be up to 50mV.
I'm finding a lot of OpAmps that say max Input Offset 6mV, 10mV, etc. Can I not use those for the 50mV signal with a non-inverting Amplifier? Not to mention the 2.5V vs 5V. Is there an OpAmp that can do this?
I want to amplify that signal 200 times to get to 10V. I take it any OpAmp can handle that... what about 10'000 times? I have another signal that is as low as 0.375 uV at the sensitivity I want so i need to amplify that 10'000 times to get it to 3.75mV which is what I can reliably read.
So basically I need 3 OpAmps. One that can take 2.5V input difference without amplification, one that can take 50mV difference and amplify 200 times, and one that can take 0.375 uV and amplify 10'000 times.
Any tips?
I'm trying to make an amplifying circuit and I'm sort of without a clue on what OpAmp to use.
I'm amplifying the result from one half-bridge from a Wheatstone bridge. The input is 5V so the output should be 2.5V + the signal I want to amplify.
In a first step I want to cancel the 2.5V by putting the 2.5V+Signal into the non-inverting input of the OpAmp and I put 5V in the inverting end with a large resistance between the 5V and the Opamp as well as a large resistance between the OpAmp inverting Input and the Output. This should let just the signal pass. (basically an inverting amplifier with the ground at 2.5V+Signal)
Then I want to amplify that signal with a standard non-inverting amplifier. The signal can be up to 50mV.
I'm finding a lot of OpAmps that say max Input Offset 6mV, 10mV, etc. Can I not use those for the 50mV signal with a non-inverting Amplifier? Not to mention the 2.5V vs 5V. Is there an OpAmp that can do this?
I want to amplify that signal 200 times to get to 10V. I take it any OpAmp can handle that... what about 10'000 times? I have another signal that is as low as 0.375 uV at the sensitivity I want so i need to amplify that 10'000 times to get it to 3.75mV which is what I can reliably read.
So basically I need 3 OpAmps. One that can take 2.5V input difference without amplification, one that can take 50mV difference and amplify 200 times, and one that can take 0.375 uV and amplify 10'000 times.
Any tips?