how many of IRFP240 will match in one batch of 100 units? - Page 2 - diyAudio
Go Back   Home > Forums > Amplifiers > Pass Labs
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Pass Labs This forum is dedicated to Pass Labs discussion.

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
Old 18th February 2013, 01:33 AM   #11
diyAudio Member
Join Date: Aug 2012
i mean not for the n and p type match but for each channel n or p...
the group size can be 6 so how many of such groups can be achieved is the question... let me try....

I think just for one pair of output since n and p need not be matched i think we can just use one n and one p for small power amp..
  Reply With Quote
Old 18th February 2013, 06:07 AM   #12
h_a is offline h_a  Europe
diyAudio Member
h_a's Avatar
Join Date: Sep 2006
Location: Graz, Austria
It largely depends on whether you can get your hands on fets that come from the same batch (same lot-code). For these matching is much more effective and has the added bonus that the other fet-properties are very similar as well.
High Octane phono preamp Wiki
  Reply With Quote
Old 18th February 2013, 03:55 PM   #13
diyAudio Member
KatieandDad's Avatar
Join Date: Nov 2011
Location: UK
Originally Posted by nigelwright7557 View Post
I have never found the need to match 240/9240's
The source resistor should help balance things.
Not in a Pass MOSFET amp. Emitter resistors yes,
  Reply With Quote
Old 18th February 2013, 04:20 PM   #14
diyAudio Member
dimkasta's Avatar
Join Date: May 2010
Location: Athens
And what voltage and current do you guys match them to?
  Reply With Quote
Old 18th February 2013, 04:56 PM   #15
flg is offline flg  United States
diyAudio Member
flg's Avatar
Join Date: Jul 2005
Location: North East
Originally Posted by KatieandDad View Post
Not in a Pass MOSFET amp. Emitter resistors yes,
In a pass MOSFET amp, what emitter Rs are you talking about? The concensous here, I agree with regarding Source Resistors. You need to match your pairs, quads etc., of the same sex, attached to one rail. It is extremely difficult and expensive to match the other sex with the other rail. IE; N-N-N match's and P-P-P match's is all that is ussually attempted. No N-P match's are easy. It is possible to match P-N but you need alot of outlying Vgs etc. parts to find matches. It is not really designed or intended to be a complementary device. You are lucky if you find matches.
"It was the perfect high end audio product: Exotic, inefficient, expensive, unavailable, and toxic." N.P.
  Reply With Quote
Old 18th February 2013, 05:19 PM   #16
diyAudio Member
oneplustwo's Avatar
Join Date: Apr 2009
Location: San Francisco
Match as closely to your intended use as you can. For the Aleph X, I did 22V at .75A for 45 seconds. IIRC, the rationale for the current and time is so that the FET doesn't heat up too much since it's not sinked during matching. If you were really hard core, you would sink it sufficiently and wait for steady state.
My Projects
  Reply With Quote


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
KEF KIT 100 subwoofer units Liliya Subwoofers 0 19th December 2012 06:35 AM
My woofer design is at 100 spl - can I match and how. joojoo1234 Planars & Exotics 6 2nd December 2011 02:32 PM
To Match Impedance on DI Box, or Not to match? MisterAlex Instruments and Amps 1 21st November 2004 10:09 AM
Batch of heatsink FrankDIY Swap Meet 1 19th March 2004 01:43 AM
IRFP240 match lot MikeZ Pass Labs 3 14th January 2003 01:15 AM

New To Site? Need Help?

All times are GMT. The time now is 10:11 AM.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999-2017 diyAudio

Content Relevant URLs by vBSEO 3.3.2