I just started working on an embedded side project that requires me to pump .wav files through headphones.
My main microcontroller is a PIC32, and my audio amplifier is an LM4862. For the DAC conversion for the audio, I am using an MCP4921 (I know it is TOTALLY the wrong chip for audio, but I've already ordered them :( )
If I replicate the "typical application" amplifier circuit in page 2 of the LM4862 datasheet, can I feed in a 0 - 3 V signal from the MCP4921 and get a reasonable volume from the LM4862? The capacitor between the audio input and the (-) input of the operational amplifier makes me uncomfortable.
Why is the capacitor there anyway? Why not put the audio input straight into the plus side of the opamp and ground the (-) side?
In my application circuit, one of the speaker inputs MUST be tied to ground. I have no way to tie it to vo1 or vo2 as per the "typical application" section of the LM4862 datasheet. How can I circumvent this? Can I just tie vo1 or vo2 low? (I don't think so). Can I leave one or the other disconnected? Should I choose a different amplifier for my application?
However, I think I will just use Ti's LM4881, which is similar to the LM4862.