
Home  Forums  Rules  Articles  diyAudio Store  Gallery  Wiki  Blogs  Register  Donations  FAQ  Calendar  Search  Today's Posts  Mark Forums Read  Search 
Class D Switching Power Amplifiers and Power D/A conversion 

Please consider donating to help us continue to serve you.
Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving 

Thread Tools  Search this Thread 
12th November 2013, 09:55 PM  #1 
diyAudio Member
Join Date: Apr 2008
Location: Carlisle, England

New project 2000 watts peak class d irs2092
Here is my latest project.
It is a stereo 1000watts per channel into 2 ohms or bridged 2000watts into 4 ohms.
__________________
MurtonPike Systems PCBCAD51 pcb design software. http://www.murtonpikesystems.co.uk 
14th November 2013, 03:56 AM  #2 
diyAudio Member
Join Date: Aug 2003
Location: NEWBURY PARK CA

class D amplifier
mmm how do you propose to obtain 1000w into 2 ohms from a split 60v rail?
Assuming a perfectly regulated power supply and a 100% efficient amplifier you can obtain 60 x 0.7071 = 42.42 volts across the load and this translates to 900w at 2 ohms. So maybe you know something none of us know, how to design a 100% efficient class D amplifier. Looking forward to seeing your schematic. Even with a perfectly regulated SMPS supply, the losses in the output MOSFETs are huge driving 40 volts plus into 2 ohms 
14th November 2013, 02:12 PM  #3  
diyAudio Member
Join Date: Apr 2008
Location: Carlisle, England

Quote:
The schematic was taken from a 1000 watt amp but with higher rails.
__________________
MurtonPike Systems PCBCAD51 pcb design software. http://www.murtonpikesystems.co.uk 

14th November 2013, 03:12 PM  #4  
diyAudio Member
Join Date: Apr 2008
Location: Carlisle, England

Quote:
60v single ended into 2 ohms is 1800 watts peak 900WRMS 60v bridged into 4 ohms is 3600 watts peak 1800WRMS
__________________
MurtonPike Systems PCBCAD51 pcb design software. http://www.murtonpikesystems.co.uk 

17th November 2013, 05:57 AM  #5 
diyAudio Member
Join Date: Jan 2004
Location: Toronto, ON, Canada

How is RMS half of peak?

17th November 2013, 08:18 AM  #6 
diyAudio Member
Join Date: Jun 2007
Location: Romania

Who is the target selfoscillation frequency ? Unfortunately I have found the answer to this question if I could see the component values, but the values can not be seen. Should consider well whether power IGBTs or MOSFETs can work well at that frequency. In those 1000W (theoretically) flow per output, power dissipation by IGBTs can reach 50W.
And some theory: peak value is 1.41 * Vrms or Vrms = 0.707 * Vpeak (for a sine wave). And power has the same addiction.
__________________
AV400v2 and GX400 audio amplifier projects PCB Design Services  for prototypes OR serial products, Today Tehnium and Forums 
17th November 2013, 04:14 PM  #7 
diyAudio Member
Join Date: Apr 2008
Location: Carlisle, England

The switching frequency is around 250KHz.
0.707 isn't that far away from half. I was being very rough with calculations. Its standard practice on ebay to say RMS is half peak.
__________________
MurtonPike Systems PCBCAD51 pcb design software. http://www.murtonpikesystems.co.uk 
17th November 2013, 04:18 PM  #8  
diyAudio Member
Join Date: Apr 2008
Location: Carlisle, England

Quote:
At 20 amps and 20 milliohms that is around half a watt or quarter watt per mosfet.
__________________
MurtonPike Systems PCBCAD51 pcb design software. http://www.murtonpikesystems.co.uk 

17th November 2013, 07:18 PM  #9 
diyAudio Member

To get the actual maximum peak signal voltage output amplitude, you still have to subtract the maximum pp ripple amplitude AND the amplifier's clipping voltage (i.e. the minimumpossible voltage between the power rail and the output, across the power output stage) at maximum output power.
So if you end up with 54 Volts max peak output (with about 75000 uF per rail per channel), that would be about 38 Volts RMS for the max output voltage. A max output voltage of 38 V RMS into 2 Ohms would give a rated max output power of 729 Watts RMS A max peak output voltage of 38 x 1.414 = 54 V pk into 2 Ohms would give a max peak output power of 54 x 54 / 2 = 1458 Watts peak. So you were correct that peak power = 2X RMS power.
__________________
The electrolytic capacitors ARE the signal path: http://www.fullnet.com/~tomg/zoom3a_33kuF.jpg 
17th November 2013, 07:27 PM  #10 
diyAudio Member

(1) P_rms = V_rms x V_rms / R
(2) P_pk = V_pk x V_pk / R (3) V_pk = √2 x V_rms Substituting (3) in (2): P_pk = √2 x V_rms x √2 x V_rms / R P_pk = √2 x √2 x (V_rms x V_rms / R) Squaring square root and recognizing (1): P_pk = 2 x P_rms
__________________
The electrolytic capacitors ARE the signal path: http://www.fullnet.com/~tomg/zoom3a_33kuF.jpg 
Thread Tools  Search this Thread 


Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
class D 1000 watts peak  nigelwright7557  Class D  8  22nd April 2013 09:24 AM 
What is a good way to measure peak watts I'm using during music?  cotdt  Solid State  51  19th September 2012 09:28 AM 
When companies state watts, is it rms or peak?  Fusion916  Solid State  11  2nd March 2012 10:26 PM 
My class d IRS2092 project  nigelwright7557  Class D  43  1st November 2010 05:20 PM 
Rockford Fosgate 2000 Watts Max  datboip  Car Audio  4  30th October 2005 04:05 PM 
New To Site?  Need Help? 