Discontinued IC's

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Hi guys,

I need you help. I was about to built my own class D amplifier with the LM4651 (and 52 ofcourse). -> LM46http://www.national.com/opf/LM/LM4651.html#Overview

The only problem is: I can't get my hands on those components since they are discontinued! Ofcourse it is easy to locate a class D amplifier IC, but i am looking for one that has 2 channels with 2x a full bridge output (about 10W or more) and an output stage that ISN'T integrated in the IC.

For some reason i keep finding ones that have the output-fets integrated :(.

I hope you guys can help me!

Regards,
Boudewijn

PS: Dont even think about the LX1720/1721/1722 since im not able to get them either (http://www.microsemi.com/micnotes/1501summary.pdf).
 
So you want an IC that has everything integrated (modulator/driver) except the FETs?

Have you considered the the IRS2092?

The 2092 is a bit of a minefield for the faint of heart.

You need to pick the right mosfets for it with low gate capacitance.
I used irfb4019.

It is also very fussy about decoupling especially around the mosfets.
I missed off by accident the B+ to B- decoupling and the 2092 kept resetting.

If you use the datasheet for the 2092 then increase teh 10uf on vcc to 47uf or you might get glicthes on the vvcc rail which will keep resetting the 2092.

If you do get it working then it sounds very good, very wide bandwidth.

I cant speak for any other devices but my experience wasnt good when the datasheet circuit wouldnt work for me.

However it not working did give me a big insight into how the chip worked and the problems associated with class d, and a partial insight into SMPS too.
 
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