CS8420 SPDIF grounding question - diyAudio
Go Back   Home > Forums > Source & Line > Digital Line Level

Digital Line Level DACs, Digital Crossovers, Equalizers, 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 21st April 2010, 10:53 AM   #1
diyAudio Member
 
Join Date: Oct 2009
Location: Brunei
Default CS8420 SPDIF grounding question

Hi all,
I am about to improve the SPDIF input on my Berhringer SRC2496 by connecting a new RCA directly to the CS8420.

I'm just a bit puzzled on the grounding. The CS8420 datasheet shows different ground points for the RCA and the chip, and I could imagine a ground loop if I would connect the ground pin of the chip (pin 5) to the cold of the RCA (RCA is grounded to the star point). On the other hand, what other ground point should I connect pin 5 to?

Or should I just leave it on the board as it should be grounded correctly in original state (in other words just connect pin 4 to the hot of the RCA and that's it?)

Thanks for helping me out here...
  Reply With Quote
Old 21st April 2010, 11:42 AM   #2
diyAudio Member
 
Join Date: Jan 2008
Location: Virginia
What ground loop are you imagining?
The ground ring of the RCA shall be connected to the board, on the ground, closest to the point where the middle is connected.
  Reply With Quote
Old 21st April 2010, 12:20 PM   #3
diyAudio Member
 
Join Date: Oct 2009
Location: Brunei
Ground loop:

Star point - PCB - CS8420 - RCA ring - Star point
  Reply With Quote
Old 21st April 2010, 03:43 PM   #4
diyAudio Member
 
Join Date: Oct 2009
Location: Brunei
Capture.JPG

So, where does the RCA ground go to? Star point?

And where does the RXN ground go to? Leave it as is as it already should be grounded properly on the PCB? Scratch the laquer off the PCB and ground it to the ground plane? Or ground it at the RCA (via cap)?
  Reply With Quote
Old 21st April 2010, 03:47 PM   #5
bocka is offline bocka  Germany
diyAudio Member
 
Join Date: Jul 2003
Location: Hannover
Quote:
Originally Posted by studiostevus View Post
So, where does the RCA ground go to? Star point?
Star ground with RF? This will never work. You need a well defined 75ohms transmission line from your RCA connector to the SPDIF receiver. Use a solid ground plane.
  Reply With Quote
Old 22nd April 2010, 11:55 AM   #6
marce is offline marce  United Kingdom
diyAudio Member
 
Join Date: Jun 2007
Location: Blackburn, Lancs
Digital should always have a GND plane, star grounds are no good (understatement) with digital. If nothing else the signal is closely coupled to the ground as at these speeds the return path follows the path of least inductance, i.e. dircectly under the signal track, no ground plane means the return has to meander all over = noise, EMC problems etc
  Reply With Quote
Old 28th November 2013, 04:27 PM   #7
diyAudio Member
 
Join Date: Apr 2012
how to conect xlr aes/ebu spdif to cs8420, can anybody help me? Mayby pictore or something.
  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
Grounding Question bigbillc Pass Labs 25 2nd January 2010 01:00 AM
Grounding SPDIF and Outputs to Chassis? mfr Digital Source 1 25th May 2004 07:05 AM
grounding question skyraider Chip Amps 1 9th March 2004 09:12 AM
CS8420 serial in-> spdif out. A 8 Digital Source 11 21st March 2003 01:15 PM
CS8420 and CS4397 question macsaif Digital Source 0 16th January 2003 06:57 AM


New To Site? Need Help?

All times are GMT. The time now is 02:34 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