Ok...I think that I might have very interesting issue here.
I have build two 200W /4ohm amplifier modules (using LM311+IR2010+IRF540Z) using core I found localy in store(unknown type but I think is ferrite) with success.
Amplifier carrier is on 300khZ,self-oscillating..tested on full power for hours (on speakers-3 way proffesional boxes) and worked great (great sound-bass,mid and highs were great).Carrier level was just 150mV.
I decided to get some samples of T106-2 core (which is a lot smaller then my core(4 inch diam.)) and try it.
I got it 2 days ago and finally tried it.
Results were not that good as I expected.
I used 2 x 20 gauge wire to make core (44 turns ) to get 40-50uH inductor....After I installed it I got ripple (carrier level) on output of 4Vp-p(old core was just 150mVp-p),offset voltage of 0.450Vmeasured using DMM (old core was 0.001V).
I found out that big offset voltage has something to do with amount of FB feeded back to comparator (I guess 3Vp-p vs. 150mVp-p) so I tried to reduce feedback but it did not work well.
Basically everything looks ok when you turn amplifier on but once you apply anything to input of LM311(even you do finger touch) it offsets Vout to 0.4V.Very strange....
Do you have any suggestion???
Regards....
I have build two 200W /4ohm amplifier modules (using LM311+IR2010+IRF540Z) using core I found localy in store(unknown type but I think is ferrite) with success.
Amplifier carrier is on 300khZ,self-oscillating..tested on full power for hours (on speakers-3 way proffesional boxes) and worked great (great sound-bass,mid and highs were great).Carrier level was just 150mV.
I decided to get some samples of T106-2 core (which is a lot smaller then my core(4 inch diam.)) and try it.
I got it 2 days ago and finally tried it.
Results were not that good as I expected.
I used 2 x 20 gauge wire to make core (44 turns ) to get 40-50uH inductor....After I installed it I got ripple (carrier level) on output of 4Vp-p(old core was just 150mVp-p),offset voltage of 0.450Vmeasured using DMM (old core was 0.001V).
I found out that big offset voltage has something to do with amount of FB feeded back to comparator (I guess 3Vp-p vs. 150mVp-p) so I tried to reduce feedback but it did not work well.
Basically everything looks ok when you turn amplifier on but once you apply anything to input of LM311(even you do finger touch) it offsets Vout to 0.4V.Very strange....
Do you have any suggestion???
Regards....