Class D amplifiers

[DonH50]

If burn-in is significant then it should matter for class D as well as any other class of amplifier. The input stage may exhibit more issues than the output stage, and I would expect (but do not know) a class D amp would be less sensitive to burn-in or warm-up than other classes.

A good op-amp should have better performance and bias/temperature stability but may have higher noise and less voltage swing than a discrete solution.

As an aside, JFETs and bipolar transistors typically exhibit significantly less noise than MOSFETs and thus are better suited for front end (low level) stages. That is due to device physics, outside the scope of this thread.

 

[nc42acc]

I sure like MOSFETS on the output. But this would be something other than Class D.

If burn-in is significant then it should matter for class D as well as any other class of amplifier. The input stage may exhibit more issues than the output stage, and I would expect (but do not know) a class D amp would be less sensitive to burn-in or warm-up than other classes.

A good op-amp should have better performance and bias/temperature stability but may have higher noise and less voltage swing than a discrete solution.

As an aside, JFETs and bipolar transistors typically exhibit significantly less noise than MOSFETs and thus are better suited for front end (low level) stages. That is due to device physics, outside the scope of this thread.

 

[DonH50]

I do not understand? MOSFETs are used in some class D output circuits (though I have not done a survey).

 

[nc42acc]

Yes and no. Remember we are comparing Class D and Class AB. The way they are implemented is completely different.

I do not understand? MOSFETs are used in some class D output circuits (though I have not done a survey).

 

[DonH50]

My post was about class D, I think I am missing your point. I was responding to the previous posts in the overall context of an amplifier, not just the output stage. I understand the differences in amplifier operation, have designed class A, AB, and D using MOSFET output stages. In any event I'll bow out rather than fill the thread with more useless drivel.

 

[nc42acc]

I am the OP and please contribute as much as you like. I don't think any technical information is drivel.