Class D university project help

danlewy

Member
2005-08-29 1:52 pm
Hi,

I have been researching and reading on this forum for some time now, a very useful resource!

I have been given a project at university to design a class D amplifier. I am pretty new to analogue design, let alone class D and audio, so I have kept my amplifier very basic. I thought it best to use a topology that is easy to design in 'stages', so although UCD etc seem the best way to go, I decided on a feedbackless design.

The specification I have to meet isn't concerned with the audio quality, it is more about understanding design choices I have made etc.

So currently I have a triangle wave oscillator using LM319 and TLE2072, feeding into the other half of the LM219 to give a PWM signal.

Then I am using the IRS20957S chip to handle level shifting and gate driving, and am using two IRFB4212 MOSFETS. The driver caused me some trouble but I finally have it working!

I would appreciate some help with designing some circuitry for the audio input signal to the comparator. I don't know what this is called or where to start looking for information. Currently I am using a signal generator as an input but would like to be able to connect it to a source such as an MP3 or CD player.

Thanks for the great community and resources available here!
 

danlewy

Member
2005-08-29 1:52 pm
I am running short of time to complete the project. I know that it will probably sound awful without feedback, but the sound quality isn't really a specification, as long as the thing works!

So how would I configure the op amp? Sorry my knowledge here is minimal.