For electrolytic capacitors in PS regulator, which voltage rating ?
63 V is good enough.
Look the evolution of this amp, now with balanced input, new thread http://www.diyaudio.com/forums/solid-state/289933-100w-cfa-mosfet-balanced-input.html#post4682489
Very nice Dadod
How is going over there? I would like to hear some opinion from others.
I have designed higher power version of the PS Regulator and it uses a MOSFET as regulating transistor.
It uses IRFP140/9140 MOSFETs and can source up to 20 A before electronic fuse was triggered.
I would need two of them but as the PCB order cost less in more quantity I would like to hear if more interested for double side PCB, dimension is 120x115 mm.
Damir
It uses IRFP140/9140 MOSFETs and can source up to 20 A before electronic fuse was triggered.
I would need two of them but as the PCB order cost less in more quantity I would like to hear if more interested for double side PCB, dimension is 120x115 mm.
Damir
Attachments
View attachment 546587
Hi Dadod.
Amplifier works.The sound is fantastic.One of the best.Bias 100mA ,dc offset 2,8mV
CFA 100W DAMIR and SLEWMASTER OPS 2pair BJT-IPS Krypton and NX amp are best amplifier I have heard.
Damir, I thank you for the great amplifier...
I am glad you like it.
You can try with somewhat higher bias of about 130 mA, and tell if there any sound different.
I can see that you stil use metal oxide feedback resistors R37/R9( if I am not wrong 5%), better use metal film 1% there.
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Now is time to replace my old Rod Elliott (ESP)3A project amplifiers with new Damir CFA's. 3 channels are ready for test for my active 3way speakers. Bias is adjusted to 140mA. I recommend to put amplifier on heatsink before adjusting. Sound is absolutely perfect, no noise, no hum.
I have found one error in the schematic and the same in the BOM. For the capacitance multipliers (Q9 and Q10) BC546/556 is not good enough, to low Vce. It should be BC546B/BC556B instead.
What function performs C3 on output (schematic 10n, bom 2n2)?
Damir,i have Q9,10 BC547B and BC557B
if voltage on your amp is more than +-45V you need BC546B/BC556B
the last "B" in BC546B and BC556B is the hFE grade.(Q9 and Q10) BC546/556 is not good enough, to low Vce. It should be BC546B/BC556B instead.
The 6 in both (BC546/556) is the Vce0 definer.
BC546 and BC556 are both 60Vce0 (Fairchild state 65Vce0), whereas the BC548/549 and BC558/559 are 30Vce0 and BC547/550 and BC557/560 are 45Vce0
Here is the last 200W-CFA-VMOSFET zip file with .asc and models files.
Damir
What software to use?
What software to use?
LTspice, free software from Linear Technology Linear Technology - Design Simulation and Device Models
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