Power amp under development

@apexaudio and all other DIY

have add Bootstrap and NMOS VI Limiter like in ARCAM

latest design improved QUASI NMOS

could this work or firework after first test ?


Optional: TRIAC DC Crowbar protection,
VI Limiter for BJTs and electronic turn on/fast off
this amplifier design dont need relay for speaker connect/disconnect
 

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Have finished today another NMOS PCB and Schematic

Does Bootstrap working like in the schematic or is it wrong ?

want order PCB for DIY but before....does somebody find any faults ?

Have add in NMOS VI limiter, Balance in, Relay free electronic Turn on delay/fast off Triac DC Crowbar protection like in commercial PA AMP



ideas for more improvement ?

waiting for good news
 

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the Baxandall diode and the capacitor are there to emulate the load that the upper BJT gives to the driver.
I don't expect the load given by an Nchannel device to need identical components to emulate the FET.

But, it would be really nice if some could confirm what changes, if any, are needed to go from BJT loading to Vfet or Lfet loading.
 
Thanks AndrewT.

Maybe someone else can chime in on this.

The Buz902DP is an excellent lateral mosfet,even though they are hard to get.
I'm looking at some Alfet N channel ALF16N20W to use in the Nmos200.

They are easier to get and cheaper than the BUZ902 series and they are made by Magnatec.

sam
 
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Here's the mini board. Could be used for multi-channel amplifiers, but also compact stereo units. Has been designed for rails up to +/- 55v (FET dependant).

Not built or tested so please check layout against schematic if you decide to use it before I build one.

As promised PCB is 75mm x 90mm (not including heatsink bracket). Have fun....

Cheers
Q

Hi Quasi, how are you bro, about this amplifier, my friend gave me 5 pcs. of this 2sk1530 and Im wondering if I can use this mosfets for this amplifier and if its not to much to ask can you please mail some latest schematics, layout and construction instruction for this great amp. thank you very much bro.😱