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steveww  
#1 Posted : Monday, November 1, 2010 2:28:34 PM(UTC)
steveww

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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

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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

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You can simply connect the toslink output directly to the wm8804.
steveww  
#4 Posted : Thursday, November 4, 2010 12:48:01 PM(UTC)
steveww

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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.
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