ucd 25 watts to 1200 watts using 2 mosfets - Page 90 - diyAudio
Go Back   Home > Forums > Amplifiers > Class D

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
Reply
 
Thread Tools Search this Thread
Old 25th February 2011, 01:16 PM   #891
norazmi is offline norazmi  Malaysia
diyAudio Member
 
Join Date: Feb 2008
go for irfb4227, its hard to get in my country, damn... need to order outside maybe online ordering...
  Reply With Quote
Old 25th February 2011, 02:54 PM   #892
diyAudio Member
 
Join Date: Apr 2010
Location: Nis, Serbia
IRFB4227. With that mosfet you can drive 2 ohm load on +-50V for 450-500W
  Reply With Quote
Old 25th February 2011, 02:57 PM   #893
diyAudio Member
 
lorylaci's Avatar
 
Join Date: Aug 2008
Location: Dabas, Hungary
Send a message via MSN to lorylaci
For +-50V rather use some 150V Fet, like:
IRFB4228, FDP2552, FDP2532, IRFB4321, IRFB4019 etc...
__________________
Olyan nem volt még, hogy ne lett volna valahogy
  Reply With Quote
Old 25th February 2011, 03:00 PM   #894
Pafi is offline Pafi  Hungary
diyAudio Member
 
Join Date: May 2004
Location: Budapest
Quote:
Originally Posted by paul14 View Post
It`s quite cheap irf540z, about 1euro.
And for +/-50v?
Do It Yourself!

For any voltage:
- make a list (parametric search) of available MOSFETs with more Vdsmax than the maximal summed power supply voltage!
- keep only the lower 1 or (at most) 2 voltage category!
- keep only the ones whose Idmax is higher by 50 % then the highest possible peak current output!
- sort them by price!
- go through the list from the cheapest to the most expensive, check if Qrr is low enough (this is dependent somewhat on switching freq, specified current, supply voltage and some other factors, but generally more than 1 uC is too high)!

For high voltage (more than 200 V): diode trick, or IGBT is needed.

Everybody! We don't know what stores can you reach and what is available at the moment!

Hints:
- IRFB4xxx is a new, very good series, still not too expensive (where available).
- TO220 is cheaper than TO247 with the same chip. As a bonus, its inductance is lower also.
- If Qg is high (more than ~100 nC), use a BC327 to discharge gate!

norazmi!

IRFP4710 and IRFB4615 are both good, the first one is better for low impedance, the other is good for higher impedance and high quality.

Last edited by Pafi; 25th February 2011 at 03:03 PM.
  Reply With Quote
Old 25th February 2011, 08:05 PM   #895
diyAudio Member
 
Join Date: Dec 2003
Location: Munich
Quote:
Originally Posted by stewin View Post
hi chocoholic

what about irfp260p


Have a look to the types which where proposed positively...and see the differences!
If you insist on the bold package: IRFP4321
Smaller packages:IRFB4321, IRFB4615, FDP2552
Check about values for gate charge, and for the data of the body diodes.
If these points don't tell you much, dig in the web for basics about switching MosFets. Application notes and papers from the semiconductor manufacturers are a good starting point.
  Reply With Quote
Old 26th February 2011, 07:45 AM   #896
norazmi is offline norazmi  Malaysia
diyAudio Member
 
Join Date: Feb 2008
Thanks Pafi, i would like to know how to setup this one as you mention, "If Qg is high (more than ~100 nC), use a BC327 to discharge gate!"

and what about totem pole discharge?
  Reply With Quote
Old 26th February 2011, 08:40 AM   #897
Pafi is offline Pafi  Hungary
diyAudio Member
 
Join Date: May 2004
Location: Budapest
norazmi!

I'm not sure what do you mean as totem pole, but anything more complex than a pnp transistor is unneccessary, because IR2110 is strong enough to charge the gate fast enough, only the discharge needs to be made faster. Connect base to IR2110, collector to source, emitter to gate, and place Rg between emitter and base!
  Reply With Quote
Old 26th February 2011, 03:35 PM   #898
norazmi is offline norazmi  Malaysia
diyAudio Member
 
Join Date: Feb 2008
aight, got it Pafi, thanks for the info, i can see more improvement on the sound. , btw mosfet also more cold than before.

regards
  Reply With Quote
Old 26th February 2011, 05:43 PM   #899
paul14 is offline paul14  Romania
diyAudio Member
 
Join Date: Oct 2010
Thank you all for info.
I studied a little and IRFB4615PBF will be suitable for my needs.
  Reply With Quote
Old 1st March 2011, 05:28 AM   #900
norazmi is offline norazmi  Malaysia
diyAudio Member
 
Join Date: Feb 2008
I go with Pafi solution, the different is noise totally gone when add transistor, very good solution.

Thanks Pafi.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Philips 40/25/15 watts amplifier with Universal preamplifier circuit. renjiish Solid State 64 28th July 2014 11:33 AM
Decibel Watts VS Watts ? fivestring Solid State 11 1st April 2009 01:08 PM
AMP1-B: why only 25 watts @8ohms? theAnonymous1 Class D 10 15th August 2005 06:55 PM
Sound quality of amps at 0.3 watts vs @ typical 5 watts rick57 Solid State 2 26th March 2005 06:25 AM
Need 2 watts Vivek Everything Else 4 17th July 2003 08:29 AM


New To Site? Need Help?

All times are GMT. The time now is 12:22 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright ©1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2