Hi all,
I am trying to build a iraudamp9 clone for subwoofer using..
So I implemented exactly the same circuit as;
http://www.google.com.tr/url?sa=t&r...wbHFBg&usg=AFQjCNGt6pqFAsgRBP2Vs_kz9kgbRgGPyg
Just the amplifier board (figure 24). And added (also tested) an auxilary 12v referenced to -V for Vcc. I have tested +/-5v onboard supplies and saw no problem.
However the amplifier did not start the PWM! Just a sawtooth (~2vpp, @4Khz) I saw on the output... And ~+16v DC offset!
By the way, my supplies are ~+/-45v and not regulated.
What do you think about that problem?
Thats a lof in advance for any kind of advice..
I am trying to build a iraudamp9 clone for subwoofer using..
So I implemented exactly the same circuit as;
http://www.google.com.tr/url?sa=t&r...wbHFBg&usg=AFQjCNGt6pqFAsgRBP2Vs_kz9kgbRgGPyg
Just the amplifier board (figure 24). And added (also tested) an auxilary 12v referenced to -V for Vcc. I have tested +/-5v onboard supplies and saw no problem.
However the amplifier did not start the PWM! Just a sawtooth (~2vpp, @4Khz) I saw on the output... And ~+16v DC offset!
By the way, my supplies are ~+/-45v and not regulated.
What do you think about that problem?
Thats a lof in advance for any kind of advice..
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Anyway...
Feedback line modification works... Thanks..
But it oscillates @ 14-18Khz! Not more. I have tried a lot of combination for oscillator circuit (C21-C23-P1-R21 and according to AN1138) but nothing's changed!
Upper MOSFET works like 90% duty cycle while the lower one works like 10% everytime!
Now where am I mistaken?
Feedback line modification works... Thanks..
But it oscillates @ 14-18Khz! Not more. I have tried a lot of combination for oscillator circuit (C21-C23-P1-R21 and according to AN1138) but nothing's changed!
Upper MOSFET works like 90% duty cycle while the lower one works like 10% everytime!
Now where am I mistaken?
Yes they alll right. In first attempt the oscillator circuit was 1n+1k pot+470+1n. But after I saw 18Khz then they replaced with 2.2n+150R+2.2.. But nothing changed.
I suggest change the 2092 !
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