I all, I am working on a small personal project that involves constructing a simple microphone preamp. The microphones I am using have a impedance rating of 680 ohms, and I am attempting to amplify their milivolt output to ~2V, which will later be fed into an ADC.
I have been doing a considerable amount of reading about opamps (very new to circuit design in general) and have begun tackling the circuit design. Unfortunately, my first attempts have not yielded the results I have expected: the 2mV input signal is not being amplified by even half of the 1000 gain inverting feedback loop.
I have a feeling that I am missing some fundamental concept about opamps, however, even after reading numerous internet resources and "Handbook of Operational Amplifier Application" (published by TI) I cant seem to figure out what is wrong with my circuit. I have attached both a screen capture of the circuit schematic and of the oscilloscope output and function generator settings (I used multisim: analog devices edition).
Any help or info on this is greatly appreciated.
p.s. could anyone recommend a good general purpose single-supply (5v) opamp that would suit non-intensive audio-preamp needs? The one I am currently simulating with is the OP490 from Analog Devices (something tells me this is not intended for general purpose/audio): http://www.analog.com/en/other/militaryaerospace/op490/products/product.html
I have been doing a considerable amount of reading about opamps (very new to circuit design in general) and have begun tackling the circuit design. Unfortunately, my first attempts have not yielded the results I have expected: the 2mV input signal is not being amplified by even half of the 1000 gain inverting feedback loop.
I have a feeling that I am missing some fundamental concept about opamps, however, even after reading numerous internet resources and "Handbook of Operational Amplifier Application" (published by TI) I cant seem to figure out what is wrong with my circuit. I have attached both a screen capture of the circuit schematic and of the oscilloscope output and function generator settings (I used multisim: analog devices edition).
Any help or info on this is greatly appreciated.
p.s. could anyone recommend a good general purpose single-supply (5v) opamp that would suit non-intensive audio-preamp needs? The one I am currently simulating with is the OP490 from Analog Devices (something tells me this is not intended for general purpose/audio): http://www.analog.com/en/other/militaryaerospace/op490/products/product.html
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