recall a classical MOSFET power supply - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

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 13th May 2004, 03:14 AM   #1
digi01 is offline digi01  China
diyAudio Member
 
digi01's Avatar
 
Join Date: Mar 2003
Location: BEIJING
Send a message via MSN to digi01
Default recall a classical MOSFET power supply

I have revised this classical mosfet AC power supply circuit again,and have making a module block now,Used for serving my series headamps.

this is the original sch scan:
Attached Images
File Type: jpg mosfet-psu.jpg (32.2 KB, 950 views)
  Reply With Quote
Old 13th May 2004, 03:15 AM   #2
digi01 is offline digi01  China
diyAudio Member
 
digi01's Avatar
 
Join Date: Mar 2003
Location: BEIJING
Send a message via MSN to digi01
this is my block psu,still in making...
Who can talk about the detail of this circuit? Or some suggestions?


-digi
Attached Images
File Type: jpg block-module.jpg (45.6 KB, 780 views)
  Reply With Quote
Old 13th May 2004, 07:10 AM   #3
hjelm is offline hjelm  Sweden
diyAudio Member
 
hjelm's Avatar
 
Join Date: Nov 2003
Location: Västerås
The E102 are they current diodes?

I have begun to wonder why the long tailed pair is not more often used in these kind of comparator scenarions. was actually thinking of doing something for a sine to square converter in a clock with a LTP, simulate at least.
__________________
Hjelm
  Reply With Quote
Old 13th May 2004, 07:28 AM   #4
digi01 is offline digi01  China
diyAudio Member
 
digi01's Avatar
 
Join Date: Mar 2003
Location: BEIJING
Send a message via MSN to digi01
This is a standard bunch mode power supply. I have done some substitution according to the device in the hand:
K213/J76-->>K214/J77,
E102-->>K246,
2SC1775/2SA872-->>B716/D756¡Á2.
it has good performance and work fine.
  Reply With Quote
Old 13th May 2004, 08:02 AM   #5
diyAudio Member
 
CheffDeGaar's Avatar
 
Join Date: Feb 2003
Location: Safe and sound
The Kubota Reg, uh ?

Nice working reg, but it should deserve some improvements IMHO. Just have a look at this post by Jonathan Carr (and the following posts too) :

http://www.diyaudio.com/forums/showt...268#post135268

I'm currently willing to implement such regs in my future preamp, and I've made some simulations, trying to improve the output impedance and the line regulation.

For the moment, I ended up replacing the emitter's resistance of the diff pairs by CCS (just a source degerated JFet for example).
Improving the voltage reference filtering with a RC network won't certainly hurt, and adding a decoupling cap for the sensing resistor bridge helps a lot.

I've attached the schematic I've used so far, but I'm sure things can be further improved, though I don't know how...

In the schematic, R2/C3/C4 provide low pass filtering for the reference. The C2 cap showed a great influence on the reg's performance (PSRR), the higher being the better...
I've added the C5-C6 caps. I found them mandatory to further reduce the output impedance below 10mOhms.

Feel free to comment/improve/flame...
Attached Images
File Type: gif mykub.gif (6.6 KB, 723 views)
__________________
/Cheff - Falling feels like flying, until you hit the ground
  Reply With Quote
Old 13th May 2004, 09:10 AM   #6
hjelm is offline hjelm  Sweden
diyAudio Member
 
hjelm's Avatar
 
Join Date: Nov 2003
Location: Västerås
Nice!

Just one question (for now) the c5 c6 they "short" the higher frequency voltage changes for the sensing thereby moving the input of the diff pair faster than without?

If so does it require some matching of the values?
__________________
Hjelm
  Reply With Quote
Old 13th May 2004, 12:05 PM   #7
diyAudio Member
 
CheffDeGaar's Avatar
 
Join Date: Feb 2003
Location: Safe and sound
Yep, sort of...
AFAIK, they provide a lower impedance network, both for the sensing bridge and the whole output, to which it is connected. I didn't invent anything, it appears in many discrete regs, even the Walt Jung's one. Here is a plot of the output impedance, showing that (in theory), it improves the Zo by a 8 factor...
Attached Images
File Type: gif zo.gif (11.8 KB, 573 views)
__________________
/Cheff - Falling feels like flying, until you hit the ground
  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
Maplin 100W mosfet amplifier - power supply problem HBrunt Solid State 32 3rd December 2013 07:11 AM
Single supply quasi complementary mosfet power amp slideman82 Solid State 8 7th March 2009 12:25 AM
MOSFET retrofit in switching power supply... GordonW Power Supplies 4 23rd March 2007 08:34 AM
power supply for Mosfet matching russbryant Pass Labs 3 12th November 2002 08:04 PM


New To Site? Need Help?

All times are GMT. The time now is 02:05 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