This is working schematic. A Discrete Class D with 2 sets of mosfet at 90Vdc supply will give you enough power to drive 18" speaker at pretty loud.
Don't ask layout 🙂
Don't commercialize 😀
Try if you like, as it is. Don't try if you doubt it.
Ltspice file is attached.
Regards,
Kartino
Don't ask layout 🙂
Don't commercialize 😀
Try if you like, as it is. Don't try if you doubt it.
Ltspice file is attached.
Regards,
Kartino
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Anyone know what schematic values need to be modified for a lower supply voltage. Say 2x40 - 2x50 volts.
I've built one of these, it doesn't work at these voltages.
So far, I've lowered R22 and R23 to about half value, but still i can't get it to work.
I've built one of these, it doesn't work at these voltages.
So far, I've lowered R22 and R23 to about half value, but still i can't get it to work.
😀😀😀
Discrete circuits got the advantage that you can repair them even after decades. The feedback after the output choke is a plus too. A more elaborate protection would be quite useful though for PA use.
Are you serious? Have you seen the cost of a low propagation delay, fully differential comparator over a 6 transistor discrete design.?
I have it
But consider cost and footprint 555 is better choice
The same reason for prestage op amp.
Never
This is first version ever I have my own UcD pro.
Later version including fullbridge UcD also very stable.
Wanted to try this, sim first.
Kartino,
I am trying to simulate your design in post 1, for the purposes of the sim leaving out the protection and font end buffers, and am getting a completely intractable -12 or so offset on the output. I am also using 80V supplies as I have several transformers that would give that voltage after rectification and filtering. I have experimented with different transistor types but that doesn't seem to matter, nor does the offset adjustment seem to do anything.
Would yo mind taking a peek at the schematic and see if I'm just blind to a mistake or if you can offer some suggestions on ridding the sim of the offset?
Kartino,
I am trying to simulate your design in post 1, for the purposes of the sim leaving out the protection and font end buffers, and am getting a completely intractable -12 or so offset on the output. I am also using 80V supplies as I have several transformers that would give that voltage after rectification and filtering. I have experimented with different transistor types but that doesn't seem to matter, nor does the offset adjustment seem to do anything.
Would yo mind taking a peek at the schematic and see if I'm just blind to a mistake or if you can offer some suggestions on ridding the sim of the offset?
Seems to, but then I'm a real newb when it comes to Class D. My historical experience is with Class A / AB. Was looking for a (mostly) discrete design and this caught my attention.
Does Cartino discret working stable same like D4K5 ?
Who does build this discret Class D Amp ?
Feedback ?
I did buid one based on OP's schematic. I'm however having some problems with it.
At +/- 90V, it seems to distort at about 20-30W output power and when probing with a scope before the output filter, it seems I'm loosing modulation for a fraction of a second - while the amp distorts sound.
Can anyone point me on what to check to fix this behaviour?
At +/- 90V, it seems to distort at about 20-30W output power and when probing with a scope before the output filter, it seems I'm loosing modulation for a fraction of a second - while the amp distorts sound.
Can anyone point me on what to check to fix this behaviour?