try here...
This is an option where i have found about 99% of all that i was interested in,everyone should try it. There are so many same answers ("Where can i find...") and unique answer for all of them is in "search" option.
This is an option where i have found about 99% of all that i was interested in,everyone should try it. There are so many same answers ("Where can i find...") and unique answer for all of them is in "search" option.
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its my pcb for this design
it works, but not good enough
high frequency distortion can be easily heard.
but frequency response at low frequency is not bad.
i check it several time but it seems has designe problem.
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What happens if the output becomes shorted for some reason? Since there are no gate source protection Zener diodes, gate source breakdown will occur when Vgs >+/-20V and because there are no source ballast resistors the transistor will probably explode.
😱 I made a power voltage regulator once and accidentally shorted the output that was not fused and a crater blew out of the plastic package where the die had vaporized. Piece of plastic hit me in the forehead...
😛
The BC517 is supposed to be mounted with the output transistors to monitor temperature. I would suggest to use a mosfet for this so that you get a closer match to the mV/C change that the output transistors will have, being that they are mosfets. The input stage might be a little light on current, I would go for at least 1 or 2mA in the input transistors. Also the input transistors need some emitter degeneration. Although mosfets do not require DC bias current to operate, the do require gate charge in order to change conduction state, related to rate of change, di/dt. This is why a driver stage is helpful. You may have compensation issues with the VAS. Output coil?
With the decoupling so far from the output transistors and no gate-drain Zobel to dampen local oscillations and no ballast resistors, I doubt much time will pass before "BBZTZZTZBZbbtbzzzttt-------p0p! pheeewww.........
followed by loud cursing.....🙂
😱 I made a power voltage regulator once and accidentally shorted the output that was not fused and a crater blew out of the plastic package where the die had vaporized. Piece of plastic hit me in the forehead...😛The BC517 is supposed to be mounted with the output transistors to monitor temperature. I would suggest to use a mosfet for this so that you get a closer match to the mV/C change that the output transistors will have, being that they are mosfets. The input stage might be a little light on current, I would go for at least 1 or 2mA in the input transistors. Also the input transistors need some emitter degeneration. Although mosfets do not require DC bias current to operate, the do require gate charge in order to change conduction state, related to rate of change, di/dt. This is why a driver stage is helpful. You may have compensation issues with the VAS. Output coil?
With the decoupling so far from the output transistors and no gate-drain Zobel to dampen local oscillations and no ballast resistors, I doubt much time will pass before "BBZTZZTZBZbbtbzzzttt-------p0p! pheeewww.........
followed by loud cursing.....🙂
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Here is a 300watt mosfet amp using irfp240/9240.
An externally hosted image should be here but it was not working when we last tested it.
