Go Back   Home > Forums > Amplifiers > Power Supplies

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 18th June 2013, 09:38 AM   #6081
diyAudio Member
 
Join Date: Jun 2006
Salas

do you recommend to add to BIB or reflektor a small value resistor to do a RC like The simplistic Salas low voltage shunt regulator
Is It nesassairy that resistor to be a premium part In order not to affect quality of CCS resistor used - Caddock MP serie
Salas hotrodded blue DCB1 build
  Reply With Quote
Old 18th June 2013, 10:10 AM   #6082
diyAudio Member
 
Join Date: Jun 2006
Quote:
Originally Posted by Salas View Post
Don't use 0.1uF local rail decoupling on the load's side when applying the 1.1 BTW.
would you please elaborate on that one
why It Is not recommended to use particular value of 0.1 uF for local decaupling
- Is It recommended to use higher value or ...
I do have 0.1 uF FT-3 and were going to use them as a pre amp power supply decoupling
  Reply With Quote
Old 18th June 2013, 02:09 PM   #6083
Salas is offline Salas  Greece
diyAudio Chief Moderator
 
Salas's Avatar
 
Join Date: Oct 2002
Location: Athens-Greece
Not 0.1uF only, small super low ESR films in general will interfere with the fixed Zobel termination of the Bib if there is not much inductance in between to really decouple and will cut a lot of phase margin. They have caused oscillation even. We had a couple of practical examples in this thread where they have caused instability that fixed with their removal. Harsher flat sound like when with EMI interference is a clue. Reflektor is more tolerant but its better without too. You can try without any film on the load's rail, short run of 4 wire cabling, or tantalum rail bypass if it has something to really do there. The shunt reg will damp the load's rail differently than a series one, especially on 4 wire connection.
  Reply With Quote
Old 18th June 2013, 02:13 PM   #6084
Salas is offline Salas  Greece
diyAudio Chief Moderator
 
Salas's Avatar
 
Join Date: Oct 2002
Location: Athens-Greece
Quote:
Originally Posted by samoloko View Post
Salas

do you recommend to add to BIB or reflektor a small value resistor to do a RC like The simplistic Salas low voltage shunt regulator
Is It nesassairy that resistor to be a premium part In order not to affect quality of CCS resistor used - Caddock MP serie
Salas hotrodded blue DCB1 build
Use a 0.33-1R after the bridge to the C filter, it cuts on charge cycle EMI. Roender said he found it good also when with 10000uF he had. MOX type will do. Depending on your Tx, diodes type, and capacitor value it may do good, nothing, or be slightly non preferable.
  Reply With Quote
Old 19th June 2013, 01:52 AM   #6085
canvas is offline canvas  Taiwan
diyAudio Member
 
Join Date: Nov 2003
Location: Taiwan
Quote:
Originally Posted by Salas View Post
Not 0.1uF only, small super low ESR films in general will interfere with the fixed Zobel termination of the Bib if there is not much inductance in between to really decouple and will cut a lot of phase margin.
Hi Salas,

How about 1.2R? My 1.2R is used to power the CD transporter which has many 0.1uf ceramics near every VCC pin. I currently put a 47uf OSCON after the power-in connector (as local bypass). Do you think these ceramics will affect the 1.2R?
  Reply With Quote
Old 19th June 2013, 02:02 AM   #6086
Salas is offline Salas  Greece
diyAudio Chief Moderator
 
Salas's Avatar
 
Join Date: Oct 2002
Location: Athens-Greece
Its a complex system to determine. Has RLC elements representing tracks and various decoupling. 1.2R is usually more difficult to disturb because it has a more sophisticated own termination. All those VCC caps add up to bigger also. Try a 47uF Tantalum in OSCON's place and no power-in connector cap at all, to evaluate what of those three works better in the total system.
  Reply With Quote
Old 19th June 2013, 06:07 AM   #6087
diyAudio Member
 
Join Date: Jun 2006
Salas

thank you for support
would you confirm that The simplistic Salas low voltage shunt regulator Is last update of 1.2R
can I use sk170 or sk117 In place of 2n5457 which Is obsolete
  Reply With Quote
Old 19th June 2013, 06:35 AM   #6088
Salas is offline Salas  Greece
diyAudio Chief Moderator
 
Salas's Avatar
 
Join Date: Oct 2002
Location: Athens-Greece
You can also use 2SK117GR for Q8,Q9.
  Reply With Quote
Old 19th June 2013, 10:42 AM   #6089
diyAudio Member
 
jackinnj's Avatar
 
Join Date: Apr 2002
Location: Llanddewi Brefi, NJ
Quote:
Originally Posted by samoloko View Post
can I use sk170 or sk117 In place of 2n5457 which Is obsolete
good lesson for those who make pcb's for group buys -- there is a surface mount version of the 2N5457 and unlike the through-hole version the pad pattern follows most other jfets. so when designing, overlay SMT pads on through hole semi's.
  Reply With Quote
Old 23rd June 2013, 04:53 PM   #6090
diyAudio Member
 
Join Date: Mar 2009
what other type of caps can be used in the reflektor for C1 and C3? instead of teflons or micas.
I intend to use the regulators to power up a pcm1794 dac

Last edited by schultzsch; 23rd June 2013 at 04:56 PM.
  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



New To Site? Need Help?

All times are GMT. The time now is 11:47 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