Single Supply Summing Amplifier: "
Hi everyone, I'm going to comment about something that happened to me today using Summing OpAmps.
First, I simulated the attached circuit in a Project Board. It's supposed to be a Single Supply summing op amp with unity gain. The thing is it never worked. The signals didnt even appear in the output. I measured with an oscilloscope the output of the op amp and there seems to be a permanent noise.
Second, I simulated the summing amplifier but with dual supplies. Because of that, i also removed the capacitors that were supposed to cleanse the DC signal going thru the input of the op amp. It worked wonderfully.
Comments about the issue please...
The IC was a TL081. Also, I simulated it with both Audio signals and signals from a Function Generator.
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