My class D amp

1/ Join all the audio ground together.
2/ Join all the power supply grounds together.

Take track from the audio ground to the edge connector where ground comes in.
This now the star ground point.
Take a track from the power supply ground to the same point.

Words explain it better than a picture.

I have used this technique on 4 audio systems now and never had a hum problem.
also it might a good idea to isolate the audio ground (signal ground) to power ground with a small value resistor.

hum (usually) won't be a problem if you work with 2-3 channels but the possibility of humming shoots up with >4 channel in a single case. in my experience at least.
 
also it might a good idea to isolate the audio ground (signal ground) to power ground with a small value resistor.

hum (usually) won't be a problem if you work with 2-3 channels but the possibility of humming shoots up with >4 channel in a single case. in my experience at least.

:confused::confused:i very much agree with you on that point .many amps i have assembled, when i use more than two channels class d i have serious noise issues . untill i change my layout or i remove preamp circuit if i am using one.:scratch::confused:
 
Last edited:
Hi Manoj,
Please give me more details.
You said it is 1000 watts - now is it stereo or mono ? Sorry I didn't read the whole thread.
You have said the voltage is 45V - is that AC or DC. Now you said you reduced it from 75 to 45. I am rewinding a Microwave transformer, so I can do either, just need a ampere rating.
Let me look through the thread for all other information. And I saw you said it sounds great. Compare the type of sound to something I might know - I have lots of vintage pioneer, marantz, yamaha etc etc. I also have listened to a bunch of newer receivers. Yamaha DSP3090 etc etc.
So You could say its like a pioneer sx 880 but has more power. That would be fine.

And how much shipped to USA.

Thanks.
Srinath.

Hi Srinath,

(a) completed working AUD600 Power AMP Board(IR MOSFET with COILCRAFT Filter),AUD600 Power Board,Signal&Clip indicator board,Volume control with limiter and Balanced input jack.(without transformer)(supply rail DC Min. +/-35V max. +/-47V) Price $180 shipping charge extra.

(b) completed working AUD600 Power AMP Board(FDA MOSFET with COILCRAFT Filter),AUD600 Power Board,Signal&Clip indicator board,Volume control with limiter and Balanced input jack.(without transformer)(supply rail DC min +/- 45V max. +/-70V) Price $185 shipping charge extra.

Spec
(a) Power FTC RMS 8R @275W
Power FTC RMS 4R @550W
Power FTC RMS 2R @1000W

(b) Power FTC RMS 8R @600W
Power FTC RMS 4R @1200W
Power FTC RMS 2R @2450W


Regards
MANOJ
 
Last edited:
1/ Join all the audio ground together.
2/ Join all the power supply grounds together.

Take track from the audio ground to the edge connector where ground comes in.
This now the star ground point.
Take a track from the power supply ground to the same point.

Words explain it better than a picture.

I have used this technique on 4 audio systems now and never had a hum problem.

thanks nigel i did exactly the above and the amp was silent and i was using smps and class d
 
That will not work, it will blow up in your face because the gate driver is a mile away from the switching fets, even if its only a 20kHz smps, the IR2110 needs to be as close to the fets as physically possible.

hi all . i modified the smps to use with the aud 900 . i made it to fit 3u space so as to easy mounting. i brought the ic closer to the output fets.


>>>>>>>>>>>for more power use igbt as outputs and increase the switching frequency by changing sg3525 rt resistor r14 from 10k to about 4.7k <<<<<<<<
 

Attachments

  • smps half bridge irfp460 smps 3u space high power bottom image.png
    smps half bridge irfp460 smps 3u space high power bottom image.png
    64.9 KB · Views: 1,218
  • smps half bridge irfp460 smps 3u space high power components.pdf
    867.6 KB · Views: 653
  • smps half bridge irfp460 smps 3u space high power pcb artwork.pdf
    245.5 KB · Views: 562
  • smps half bridge irfp460 smps 3u space high power schematic .pdf
    35.6 KB · Views: 576
  • smps half bridge irfp460 smps 3u space high power top and bottom image.png
    smps half bridge irfp460 smps 3u space high power top and bottom image.png
    82.8 KB · Views: 1,203
  • smps half bridge irfp460 smps 3u space high power top image.png
    smps half bridge irfp460 smps 3u space high power top image.png
    60 KB · Views: 1,153
Last edited: