Hi everyone,
Thank you for all your advices in this forum, that's splendid !
I'm currently building an H-Bridge Amplifier. I'm a beginner in the conception of amplifier but I'm starting to understand the mood !
In this project I do have a bill of specifications such as using an asymmetrical alimentation (will be a PC one) and using ThermalTrak as output transistors so don't be surprised.
I've almost finished it, but I have encountered a problem with the THD. I am at almost 0.2% at 20 kHz (0,013 % at 1kHz) on each part of the amplifier that are inspired from the Blameless amplifier of Self, and same THD for the output of the H-Bridge.
I know that H-bridge is supposed to reject odd harmonics and so, reduce THD, but there it doesn't. I have connected the 2 amplifiers in parallel, one in non-inverser configuration, and the other in inverser. On the second one, I have adjusted the closed loop gain a bit differently so it could be almost the same amplitude at the output than the non-inverser.
Could it be there the problem of non-rejection? Or maybe the poles are different on each amplifier which affects the output. Don't really know.
Do you think we could reach the odd harmonics rejection with this topology of H-Bridge amplifier?
Thank you a lot for your help.
Thank you for all your advices in this forum, that's splendid !
I'm currently building an H-Bridge Amplifier. I'm a beginner in the conception of amplifier but I'm starting to understand the mood !
In this project I do have a bill of specifications such as using an asymmetrical alimentation (will be a PC one) and using ThermalTrak as output transistors so don't be surprised.
I've almost finished it, but I have encountered a problem with the THD. I am at almost 0.2% at 20 kHz (0,013 % at 1kHz) on each part of the amplifier that are inspired from the Blameless amplifier of Self, and same THD for the output of the H-Bridge.
I know that H-bridge is supposed to reject odd harmonics and so, reduce THD, but there it doesn't. I have connected the 2 amplifiers in parallel, one in non-inverser configuration, and the other in inverser. On the second one, I have adjusted the closed loop gain a bit differently so it could be almost the same amplitude at the output than the non-inverser.
Could it be there the problem of non-rejection? Or maybe the poles are different on each amplifier which affects the output. Don't really know.
Do you think we could reach the odd harmonics rejection with this topology of H-Bridge amplifier?
Thank you a lot for your help.
Attachments
2N3904/2N3906
Wont work as drivers Use KSA1381 / KSC3503
C3/C7 should be 100u or larger
R7/R13 to high should be 470 to 560 ohm
C2/C4 should be smaller 15p to 27p
Using high value like 250p is why high frequency
distortion is suffering
Wont work as drivers Use KSA1381 / KSC3503
C3/C7 should be 100u or larger
R7/R13 to high should be 470 to 560 ohm
C2/C4 should be smaller 15p to 27p
Using high value like 250p is why high frequency
distortion is suffering