WM8816 question - diyAudio
Go Back   Home > Forums > Source & Line > Digital Source
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

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
Thread Tools Search this Thread
Old 1st July 2004, 11:37 PM   #1
diyAudio Member
Join Date: Jan 2004
Location: Hudiksvall
Default WM8816 question


I'm a little bit confused, in WM8816 datasheet it says that AVDD & DVDD pins must be tied together in all designs because damage can be caused if supply voltages differ to any degree.

But in WM8816 Ev. board datasheet they have one 7805 for each AVDD & DVDD.

Whats the way to go? Split groundplane and split AVDD & DVDD or split groundplane and use the same supply for AVDD & DVDD.

This is my first pcb layout ever so plz let me hear your opinion.
Just wanna know if its totaly wrong and so on.

The traces for the controller is'nt there yet...

Layout & Top and Bottom Eagle 3D files (warning BIG .bmp files)

/Thanks in advance
  Reply With Quote
Old 1st July 2004, 11:39 PM   #2
diyAudio Member
Join Date: Jan 2004
Location: Hudiksvall
Oh, and this is 1 channel balanced. Eagle freeware you know...
  Reply With Quote
Old 2nd July 2004, 09:24 PM   #3
diyAudio Member
Join Date: Jan 2004
Location: Hudiksvall
Someone? grondplane question.
.bmp gone .jpg now on my homepage
  Reply With Quote
Old 2nd July 2004, 09:25 PM   #4
diyAudio Member
Join Date: Jan 2004
Location: Hudiksvall
Oh, supplyquestion I mean.
  Reply With Quote
Old 2nd July 2004, 09:40 PM   #5
diyAudio Member
jan.didden's Avatar
Join Date: May 2002
Location: The great city of Turnhout, BE
Blog Entries: 8

I have the eval module for testing, you are right there are separate regs. I think they mean that the supply levels should be the same, NOT that they should be physically tied together, that would make no sense.

Jan Didden
Music is dither to the brain; lets me think below the usual chaos - me
Linear Audio Vol 13 is out! Check out my Autoranger and SilentSwitcher
  Reply With Quote
Old 14th July 2004, 09:49 AM   #6
Robin is offline Robin  United Kingdom
diyAudio Member
Join Date: Feb 2004
Location: East Midlands
I have had communication with Wolfson recently on this point and they tell me that the recommendations in the datasheet are recommended over what is suggested in the eval design. . Apparently, their advice these days is that the supplies (AVDD and DVDD) DEFINITLY need to be tied together from the same supply. Their communication was as follows:

"We would strongly advise that the AVDD and DVDD power supplies are connected to the same supply. There is a slight inconsistency between the schematic in the Evaluation Manual and the datasheet as the schematic is based upon the evaluation board, which has separate regulators with power supplies taken from the same input terminal, while the datasheet is more recent and amended much more regularly.

All applications advice should be taken from the datasheet while the schematic should only be used for layout ideas only, it is not really meant as an absolute reference design. There is no plan to change the Evaluation Board design. Running from the same supplies will not have an affect on performance. I hope this will not cause you any inconvenience.

I hope this helps some of you guys out there experimenting with this device.

  Reply With Quote
Old 14th July 2004, 01:32 PM   #7
diyAudio Member
Join Date: Jan 2004
Location: Hudiksvall
Thanks Robin! that helped alot.

So, is it really any idea to split groundplane if lets say I'm only gonna have input -> WM8816 -> OP -> output ?

  Reply With Quote


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
WM8816 based pre-amp panson_hk Chip Amps 13 22nd May 2009 02:16 PM
Where to get WM8816 yangsmm Parts 5 15th July 2008 09:33 AM
WM8816-LM4562 Board Design Gcollier Chip Amps 24 15th October 2006 04:20 PM
Source for WM8816 Gcollier Parts 1 13th March 2006 06:04 PM
WM8816 Control IC/Board? mbcouple Digital Source 6 27th June 2005 02:59 PM

New To Site? Need Help?

All times are GMT. The time now is 03:56 AM.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999-2017 diyAudio

Content Relevant URLs by vBSEO 3.3.2