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Yes it can. The feedback makes it essentially an op amp, with the output voltage being a ratio to the input voltage. There will still be distortion, and the intermediate signals could be quite distorted, but the output should follow the input quite well, even though the driving signals for the final stage will not.Bob,
Not so ,the feedback can't take care of the transistors mismatch!
and yes there are paired power Mosfets see here
i'll probably use paired transistors, as it will cost at least 5 dollars more. thanks guys!
thanks for your linkWhat made you think you can use anything but a matched pair?
To any Hi-Fi audio (class AB complimantry) power amp the Output Stage matched pair is a fundamental MUST requirement !!!
That is critical for "ultra high-end " LM4702 type circuit performance .
Here is a TI app note(your circuit is taken from it) dealing mostly with the performance of matched pairs from different vendors.(there is a summary of performance comparison on page 27).
I think it will help you a lot.
AN-1645 : LM4702 Driving a MOSFET Output Stage
thanks for your link
why can't you just adjust the gain on Rgn1 and Rgn2? isn't it there for that reason?
i am basing my design off of other peoples. i have decent knowledge, and quite some soldering and pcb experience. I don't have the budget to buy 1000 transistors just to pair it, i will probably buy paired transistors, so i don't need really high end test equipment. Even though people have suggested to not use usb scopes, i will be using a really hi-fi soundcard as a scope, as it's accuracy is pretty darn high. it won't be the the best solution, but it will work for now, i'm only working with frequencies from 20-20k.No,the gate resistors don't adjust gain.
Their purpose is totally different:
Maintain the Amp stability(prevent oscillations of the Amp.)
Look at section 7.1
I'm wondering, are you actually going to build the AMP?
To be able to build a ultra-HiFi High Power AMP needs a lot of Knowledge and experience...
And, to be able to test it's performance requires very expansive Hi-End test equipment,which I'm sure you don't have...
So what gives?
i am basing my design off of other peoples. i have decent knowledge, and quite some soldering and pcb experience. I don't have the budget to buy 1000 transistors just to pair it, i will probably buy paired transistors, so i don't need really high end test equipment. Even though people have suggested to not use usb scopes, i will be using a really hi-fi soundcard as a scope, as it's accuracy is pretty darn high. it won't be the the best solution, but it will work for now, i'm only working with frequencies from 20-20k.