Thanks 
Unfortunately i can't try that, this section is already completed and I have only two months to complete this project (also with boxes and 40page documentation - I don't have written anything) and also because it already cost me a lot of money
The only thing that i could try is changing the resistors
Unfortunately i can't try that, this section is already completed and I have only two months to complete this project (also with boxes and 40page documentation - I don't have written anything) and also because it already cost me a lot of money
The only thing that i could try is changing the resistors
With no audio and no input (Audio IN and GND in short circuit) I can still hear a small noise coming from the arc (doesn't depend on frequency), but i must have my ear really near the arc. It's clear when modulator is not overexcited, when it is i can hear some snizzling. But the sound is not loud when not overexcited, one like a small high frequency speaker. When overexcited the speaker is louder than my common PC speakers.
newvirus2008:
Student in final year of High shool of electrical engineering. (secondary school)
newvirus2008:
Student in final year of High shool of electrical engineering. (secondary school)
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In school? No! Nobody cares about schematics in our projects. Most of students just take a schematic, make it, test it and don't care how it works or how to upgrade it. Even nobody cares about PCB design. If it is not working, try to take another schematic or try to make it again. This conforms both students and teachers.
And I'm just little bit inquisitive
If you ment in this phorum, i didn't notice it.
And I'm just little bit inquisitive
If you ment in this phorum, i didn't notice it.
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Ah yes now i remember. I wrote that I can't use it, because it is impossible to buy drivers here. I thought on the PWM is important only the width of the pulse. How can this forward converter change width pulse and bring noise into the PWM signal?
No the sound quality is not very important, but i want to know and try ways how to improve it. And if it is possible, implement it.
No the sound quality is not very important, but i want to know and try ways how to improve it. And if it is possible, implement it.
The half bridge driver can pull up and down equally well. The forward converter (that pulls up through the load which is inductive and thus loses symmetry of square wave) is mainly used in DC/DC converters, not in DC/AC systems like inverters or amplifiers.
Also, I ve tried making a class D amp with a forward converter. It works, but cracks and distorts when input is loud. I think it suits DC/DC apllns only. Also, the MOSFET heated up very much.
Also, I ve tried making a class D amp with a forward converter. It works, but cracks and distorts when input is loud. I think it suits DC/DC apllns only. Also, the MOSFET heated up very much.
The drive currents are way too low for a D-amp. 130mA and 270mA are too low to drive MOSFETS (in a D-amp, not everywhere else)
Can t you get LM5101 (this has TTL compatible inputs that can be driven from you TTL flipflop) and can do 1/2 or 3 Amperes.
Also this chip has the bootstrap diode built into it. IR2101 is too weak.
More Amperes => better rise and fall time. Also, half bridge has two devices and you ll need to set dead time etc. But you may easily get rid of transformer saturation as the DC component is eliminated altogether (if used with dual supply)
Can t you get LM5101 (this has TTL compatible inputs that can be driven from you TTL flipflop) and can do 1/2 or 3 Amperes.
Also this chip has the bootstrap diode built into it.
IR2101 is too weak.More Amperes => better rise and fall time. Also, half bridge has two devices and you ll need to set dead time etc. But you may easily get rid of transformer saturation as the DC component is eliminated altogether (if used with dual supply)
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Through todays testing i have found that most of the sizzling is not made by overexciting. It's done because the D-flip flops malfunction. The frequency is doubled for a while and that makes the sizzling.. With proper shielding the sound is much cleaner and there is just a little when overexcited.
With proper shielding the sound is much cleaner and there is just a little when overexcited.Thats better for you because you have made a schematic and PCB for the forward converter, assembled it and got it to work and hence may the half bridge a burden .
BTW are the flip flops being disturbed by the 'power' areas on the board ??
Could you post a picture of the whole thing (with the shielding of course)?
BTW are the flip flops being disturbed by the 'power' areas on the board ??
Could you post a picture of the whole thing (with the shielding of course)?
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