Dynamic Bias - Active Bias - Automatic/Self biased - Overview wanted

PRR

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Who can upload this AES paper:
AES E-Library >> THE AUTOBIAS AMPLIFIER: A New Topology for Automatically Biased Audio Amplifiers Using Power MOSFETs....

AES papers are copyright. They probably should not be posted.

What seems to be the same article was published in a book:

MOSPOWER applications – 1984 - Rudy SEVERNS
Publisher: Siliconix, 1985
ISBN 10: 0930519000 ISBN 13: 9780930519001

This is the most MOSPOWER info ever put between two covers.

You can buy your own for not a lot of money.
MOSPOWER applications handbook: Rudy (ed) SEVERNS: Amazon.com: Books
Mospower Applications Handbook by Rudy Severns - AbeBooks
 
Thank you for this posting.
By chance I have discover various BIAS servo IC's like Pioneer's PA0016 - go to
Предложено На Форуме - Страница 2 - Усилитель мощности А. Лайкова - Форум по радиоэлектронике
Are the internal circuit from the attachment well suited as a replacement for common vbe multiplier? Or should I prefer one of the other showed designs (JVC's VC5022, ROHM's BA3122N or one of the discrete design's) ?
What are the pros and cons of each ?
Check out also post #15 under
Help with schematic
Thank you very much for advices.
 

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Thank you for this posting.
By chance I have discover various BIAS servo IC's like Pioneer's PA0016 - go to
Предложено На Форуме - Страница 2 - Усилитель мощности А. Лайкова - Форум по радиоэлектронике
Are the internal circuit from the attachment well suited as a replacement for common vbe multiplier? Or should I prefer one of the other showed designs (JVC's VC5022, ROHM's BA3122N or one of the discrete design's) ?
What are the pros and cons of each ?
Check out also post #15 under
Help with schematic
Thank you very much for advices.

PA0016 clone:
RT22.RU Радиотехника 20 века, форумы • Просмотр темы - Микросхемы Pioneer PA0016
 

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A colleague, who was no slouch, failed to get the LT1166 from oscillating into some loads. A lovely idea, but it had issues.

I successfully adapted Mr Gevel's approach from N FETs to complimentary triple emitter followers. It instantaneously set up bias, was non switching and halved THD at HF (the crossover residual) on and already clean amp. 8 biploars and some passives.
 
I worked with them for a while, and finally gave up. Smarter than me,
Bob Cordell doesn't seem to have been happy with them either.

:snail:

It is quite easy to do with discrete matched pairs of transistors. The 10:1 ratio LT1166 has takes more parts, so I changed it to the constant sum of 2 exponents. The quiescent ends up a little higher than optimally biased class B, but the zero switching and smooth transition seems worthwhile, along with the zero settling time in production. Also you can remove the emitter resistors and use collector resistors to sense the current if that takes your fancy.
 
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It is quite easy to do with discrete matched pairs of transistors. The 10:1 ratio LT1166 has takes more parts, so I changed it to the constant sum of 2 exponents. The quiescent ends up a little higher than optimally biased class B, but the zero switching and smooth transition seems worthwhile, along with the zero settling time in production. Also you can remove the emitter resistors and use collector resistors to sense the current if that takes your fancy.

So now it's Wayne, ZM, Rothacher, Cordell and you that's smarter than me.

:snail:
 
So now it's Wayne, ZM, Rothacher, Cordell and you that's smarter than me.

:snail:

No no sir. Mr Gevel maybe on your level, but I merely get inspired from those who are around me, and re-arrange things until they work and sound better...

I have a couple of other versions, including a rail to rail one using p-channels on the positive rail and n-ch on the negative. I haven't built that one yet. Young engineers appear to be scared of the 3 legged devices, and it was vetoed on their protestations.