Hi,
I am working on a project where I am designing an audio amplifier. The amplifier I decided to use uses differential inputs. (a IN+ and IN- signal)
Since I need differential inputs, I decided to easiest way was to use an inverting amplifier to get the IN- signal. Everything seems to work great, my audio is getting amplified, and sound is good. However, there a problem. My inverting amplifier is outputing a high pitched noise. I've narrowed it down to my inverting amplifier. I removed my inverting amplifier, and just powered on the audio amplifier, and the high pitched noise is not there. I put back the inverting amplifier, and the noise is there. I can tell you the IN+ signal does not have the noise. Only the IN- signal. Attached is a schematic of my inverting amplifier, and my audio amplifer I am using. Any help would be appreciated, thanks.
The V+ for the LM358 is +5V.
I am working on a project where I am designing an audio amplifier. The amplifier I decided to use uses differential inputs. (a IN+ and IN- signal)
Since I need differential inputs, I decided to easiest way was to use an inverting amplifier to get the IN- signal. Everything seems to work great, my audio is getting amplified, and sound is good. However, there a problem. My inverting amplifier is outputing a high pitched noise. I've narrowed it down to my inverting amplifier. I removed my inverting amplifier, and just powered on the audio amplifier, and the high pitched noise is not there. I put back the inverting amplifier, and the noise is there. I can tell you the IN+ signal does not have the noise. Only the IN- signal. Attached is a schematic of my inverting amplifier, and my audio amplifer I am using. Any help would be appreciated, thanks.
The V+ for the LM358 is +5V.
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