Good sources for high-V (600V) Schottky diodes? - diyAudio
Go Back   Home > Forums > Design & Build > Parts

Parts Where to get, and how to make the best bits. PCB's, caps, transformers, etc.

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 20th March 2007, 07:47 PM   #1
GordonW is offline GordonW  United States
diyAudio Member
 
GordonW's Avatar
 
Join Date: Mar 2005
Location: Marietta/Moultrie GA
Default Good sources for high-V (600V) Schottky diodes?

Looking to upgrade the B+ rectifiers on my old HK Award A300 tube amp.

It'd need two 600v Schottky diodes, to do it right. 1 amp should be PLENTY, I'd think.

However, I've only found limited availability of these... nothing that was JUST right. Anyone got any good sources for these things? Basically, a standard "axial" configuration (ie, one wire out each end) would be best...

Regards,
Gordon.
__________________
Speaker Design, Restoration and Repair- since 1985.
  Reply With Quote
Old 20th March 2007, 07:48 PM   #2
Duo is offline Duo  Canada
diyAudio Member
 
Duo's Avatar
 
Join Date: Jun 2002
Location: Victoria, BC, Canada
Send a message via ICQ to Duo
Why does this amplifier require schottky diodes?
  Reply With Quote
Old 21st March 2007, 02:53 PM   #3
GordonW is offline GordonW  United States
diyAudio Member
 
GordonW's Avatar
 
Join Date: Mar 2005
Location: Marietta/Moultrie GA
More graceful on-off characteristics than regular junction diodes... less switching noise. The characteristics of a Schottky more resemble that of a tube rectifier, but with much less voltage drop.

The HK originally had solid-state diodes... which had bypass caps on them, to try and snub the switching noise. With the Schottkys, there should be almost no noise TO have to bypass/filter...

Regards,
Gordon.
__________________
Speaker Design, Restoration and Repair- since 1985.
  Reply With Quote
Old 21st March 2007, 03:09 PM   #4
Account Disabled
 
Join Date: Sep 2004
Location: Earth
search for the HFA08TB60

they're not axial though............ but too fast
  Reply With Quote
Old 23rd March 2007, 03:41 PM   #5
diyAudio Member
 
serengetiplains's Avatar
 
Join Date: Feb 2004
Location: Canada
Parts Connexion sells them.
  Reply With Quote
Old 24th March 2007, 06:13 PM   #6
GordonW is offline GordonW  United States
diyAudio Member
 
GordonW's Avatar
 
Join Date: Mar 2005
Location: Marietta/Moultrie GA
Found them. Cree 600v, 2A. From Digikey. Less than $2 each!

They also have 1200V; in this case, I only needed 400V minimum, so the 600V were perfect...

Regards,
Gordon.
__________________
Speaker Design, Restoration and Repair- since 1985.
  Reply With Quote
Old 24th March 2007, 07:11 PM   #7
diyAudio Member
 
serengetiplains's Avatar
 
Join Date: Feb 2004
Location: Canada
Nice find, Gordon. Say, can these devices be paralleled, without more, for greater current handling?
  Reply With Quote
Old 24th March 2007, 11:55 PM   #8
diyAudio Member
 
Join Date: Jan 2007
Quote:
Originally posted by serengetiplains
Nice find, Gordon. Say, can these devices be paralleled, without more, for greater current handling?
I would recommend against that, because if the junction voltage drops aren't exactly equal, the current distribution will be highly asymmetrical and thus you will not benefit from the parallel connection.

On the other hand, Schottkies have a lower voltage drop than regular diodes, so I would not expect them to heat up very significantly. Has anyone ever tried running these things "over spec"?
  Reply With Quote
Old 25th March 2007, 03:47 AM   #9
jcx is offline jcx  United States
diyAudio Member
 
Join Date: Feb 2003
Location: ..
parallel with balancing resistors

semi diodes are going to be way lower impedance than any tube they replace

and don't count on exceeding power device ratings - the marketing guys would dearly love to put bigger # on the data sheet, they often get sneaky by specifying unrealistically optimistic heatsinking as is - cautious engineers often derate device operating conditions to <50% of the data sheet value
  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
Where can I buy schottky diodes in Australia ? lordvader Parts 2 29th November 2007 09:57 PM
mandatory Schottky diodes ? coresta Class D 4 5th June 2007 01:52 AM
IR Hexfred diodes - HFA50PA60 600V, 50A spitz Swap Meet 5 5th July 2004 01:39 PM
Aleph-X builders LOOK!! HIGH-power (real!) dual Schottky diodes for sale cocolino Swap Meet 11 5th March 2004 08:56 AM
International Rectifier Schottky diodes KevinLee Swap Meet 17 30th June 2003 09:37 PM


New To Site? Need Help?

All times are GMT. The time now is 08:02 AM.


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