Welcome Guest! To enable all features please Login or Register.

Notification

Icon
Error

Login


Options
View
Go to last post Go to first unread
steveww  
#1 Posted : Monday, November 1, 2010 2:28:34 PM(UTC)
steveww

Rank: Advanced Member

Groups: Member
Joined: 10/18/2010(UTC)
Posts: 36
Location: UK

I have the 8804 module and the Toslink module.

AFAIK the 8804 is configured by default to use a comparator input on RX0 (500mVppAC) and the Toslink module outputs 3.3V logic.

Any suggestions on how to interface these two?
steveww  
#2 Posted : Thursday, November 4, 2010 1:38:33 AM(UTC)
steveww

Rank: Advanced Member

Groups: Member
Joined: 10/18/2010(UTC)
Posts: 36
Location: UK

So many views and still no answer.

The answer is to use a simple voltage divider. Remember the toslink module can only source/sink 2mA, so make the divider resistance is suitably high enough.
Brian Donegan  
#3 Posted : Thursday, November 4, 2010 4:29:57 AM(UTC)
Brian Donegan

Rank: Administration

Groups: Administration, Customer
Joined: 10/24/2006(UTC)
Posts: 2,868
Location: Massachusetts, USA

Thanks: 2 times
Was thanked: 141 time(s) in 134 post(s)
You can simply connect the toslink output directly to the wm8804.
steveww  
#4 Posted : Thursday, November 4, 2010 12:48:01 PM(UTC)
steveww

Rank: Advanced Member

Groups: Member
Joined: 10/18/2010(UTC)
Posts: 36
Location: UK

OK. I was concerned that the 3.3V output from the toslink module could cause problems when the 8804 is configured for 500mV. Also the 8804 board has a 75 ohm input impedance, 3.3V into this results in 44mA which is considerably more than the 2mA source / sink specified for the toslink module.
Rss Feed  Atom Feed
Users browsing this topic
GuestUser
Forum Jump  
You cannot post new topics in this forum.
You cannot reply to topics in this forum.
You cannot delete your posts in this forum.
You cannot edit your posts in this forum.
You cannot create polls in this forum.
You cannot vote in polls in this forum.