Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Simplistic Mosfet HV Shunt Regs
Simplistic Mosfet HV Shunt Regs
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 30th December 2013, 01:13 AM   #4281
king4joy is offline king4joy  Hong Kong
diyAudio Member
 
Join Date: Apr 2011
Quote:
Originally Posted by Salas View Post
That part is a classic cascode for CCS, it was around, later I saw it analyzed in Morgan Jones 4th edition book also. A very good book to get, recommended. There is nothing much to it, you just put it where you would put an anode resistor and you turn its trimmer to fix a current. If it will not work that will only be if something is damaged. Good thing its also workable in low voltage so you can model and fix it safely. You can use an Led instead of a tube in that modeling and some 20V supply. Or a small resistor. That's all there is to it.
Salas,

I have been doing some modeling with the CCS, with 12VDC only (my line amp still at friendís place), loaded with a 620R resistor.

Playing around, with 12VDC in, loaded with 620R, the best range of the CCS I can get is 20.9mA to 5.8mA, with R3 = 1K (R4 = 500R trimmer)......further increase of R3 value did not change the range much. Click the image to open in full size.


Would you give a hint what combination of R3 and R4 I should try, to get a range of 10mA to say about 25-30mA when loaded with a VT25A please??

Thankyou, and Happy New Year!!
  Reply With Quote
Old 30th December 2013, 01:20 AM   #4282
king4joy is offline king4joy  Hong Kong
diyAudio Member
 
Join Date: Apr 2011
above becomes Click the image to open in full size. , I don't know how....
  Reply With Quote
Old 30th December 2013, 02:08 AM   #4283
Salas is online now Salas  Greece
diyAudio Chief Moderator
 
Salas's Avatar
 
Join Date: Oct 2002
Location: Athens-Greece
Simplistic Mosfet HV Shunt Regs
Try at higher Vds also. 25-30V.
  Reply With Quote
Old 30th December 2013, 02:35 AM   #4284
luvdunhill is offline luvdunhill  United States
diyAudio Member
 
luvdunhill's Avatar
 
Join Date: Jul 2006
king4joy: Apply Ohm's Law and you might learn a thing or two. Start with your load resistor. Also, check out SY's "Impasse" article in AudioXpress which explains how this CCS works.
  Reply With Quote
Old 30th December 2013, 03:09 PM   #4285
king4joy is offline king4joy  Hong Kong
diyAudio Member
 
Join Date: Apr 2011
Quote:
Originally Posted by Salas View Post
Try at higher Vds also. 25-30V.
How do I try higher Vds??

Will higher VDC input give a higher Vds??

What VDC input would you recommend to use when modeling for the real VDC input of 248VDC ??
  Reply With Quote
Old 30th December 2013, 11:08 PM   #4286
Salas is online now Salas  Greece
diyAudio Chief Moderator
 
Salas's Avatar
 
Join Date: Oct 2002
Location: Athens-Greece
Simplistic Mosfet HV Shunt Regs
Use 30VDC or something about there. Low VDC modeling is just to verify your circuit works in safe experimenting. The real max mA you will evaluate on the real amp voltages.
  Reply With Quote
Old 31st December 2013, 12:13 AM   #4287
king4joy is offline king4joy  Hong Kong
diyAudio Member
 
Join Date: Apr 2011
Quote:
Originally Posted by Salas View Post
Use 30VDC or something about there. Low VDC modeling is just to verify your circuit works in safe experimenting. The real max mA you will evaluate on the real amp voltages.
In my amp, I am using 1 x SSHV2, TP set at 50mA, feeding a pair of these CCS, with R3 = 330R and R4 = 500R trimmer, with 248VDC, I can onlt get max about 9.0mA with the CCS.

What values for R3 and R4 should I try next please??

Happy New Year
  Reply With Quote
Old 31st December 2013, 12:17 AM   #4288
king4joy is offline king4joy  Hong Kong
diyAudio Member
 
Join Date: Apr 2011
Do you think I need to set the SSHV2 at higher than 50mA ??
  Reply With Quote
Old 31st December 2013, 12:17 AM   #4289
Salas is online now Salas  Greece
diyAudio Chief Moderator
 
Salas's Avatar
 
Join Date: Oct 2002
Location: Athens-Greece
Simplistic Mosfet HV Shunt Regs
220R both I guess.
  Reply With Quote
Old 31st December 2013, 12:19 AM   #4290
Salas is online now Salas  Greece
diyAudio Chief Moderator
 
Salas's Avatar
 
Join Date: Oct 2002
Location: Athens-Greece
Simplistic Mosfet HV Shunt Regs
Quote:
Originally Posted by king4joy View Post
Do you think I need to set the SSHV2 at higher than 50mA ??
If you are introducing new extra consumption at the load, reg setting should go accordingly.

Happy new year 2u2.
  Reply With Quote

Reply


Simplistic Mosfet HV Shunt RegsHide 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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Regs - Shunt vs Series richie00boy Solid State 59 17th June 2017 03:59 PM


New To Site? Need Help?

All times are GMT. The time now is 04:08 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.00%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio
Wiki