shield ic chip at analog ground or digital ground? - diyAudio
Go Back   Home > Forums > Source & Line > Digital Source

Digital Source Digital Players and Recorders: CD , SACD , Tape, Memory Card, 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 17th July 2012, 03:45 AM   #1
diyAudio Member
 
Join Date: Oct 2002
Location: Winnipeg MB Canada
Default shield ic chip at analog ground or digital ground?

Hello,


I am going to shield a few ic in my Quad 99 CDP with conductive copper and conductive aluminum tape.

If an IC has both an analog ground and a digital ground, which one should i connect the shield to?

One chip for example is a Cirrus CS4396.

Thanks

Kevin
  Reply With Quote
Old 17th July 2012, 06:36 AM   #2
Mooly is offline Mooly  United Kingdom
diyAudio Moderator
 
Mooly's Avatar
 
Join Date: Sep 2007
It probably won't make much difference in practice. (Both adding foil and where connected.)

Another slant is that the foils will (could ) pick up noise and inject it into the grounds. It works both ways although the effect would be microscopic I'm sure..

Perhaps connect the foils back to some main PSU ground (or the case) via isolating resistors of say 10 ohm...
__________________
-------------------------------------------------------
A simulation free zone. Design it, build it, test it.
  Reply With Quote
Old 17th July 2012, 12:15 PM   #3
marce is offline marce  United Kingdom
diyAudio Member
 
Join Date: Jun 2007
Location: Blackburn, Lancs
Dont bother untill you have read Henry Ott, Electromagnetic compatability engineering, then you will realise that it aint gonna do much.Shielding is an art itself, and if you have any holes or slots its a waste of time. If you look at the cans on PCB's for shielding, they have a contigous soldered join at the bottom where the ground is exposed to create a 360 degree join, you will not achieve this with foil or tape and as Mooly said may cause more noise by creating unintentional dipoles. Adding tails to some remote location is the worse thing you can do with a shield, they have to be connected at source and all the way around the shield. As the digital ground (if seperate ) will tend to be more imune to noise than analogue use the digital ground if you must play.
  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
Preamp Umbilical - Use Shield as Ground Lead? Magz Tubes / Valves 16 9th May 2011 04:33 PM
Parallel LM3886, input ground, power ground, safety resistor and oscillations. markiemrboo Chip Amps 5 9th August 2007 03:50 PM
Ground shield connections question rtarbell Solid State 4 3rd September 2006 09:12 AM
Chassis Ground = Circuit Ground --> Problems? rhildenbrand Pass Labs 5 23rd April 2004 01:08 AM
does connecting mains ground with circuit ground create a ground loop? jarthel Everything Else 0 25th June 2003 12:55 PM


New To Site? Need Help?

All times are GMT. The time now is 01:04 PM.


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