#12548 HIGH 13.1.0: Test DC input (sensors) on XO-4

Zarro Boogs per Child bugtracker at laptop.org
Wed Feb 13 17:04:17 EST 2013

#12548: Test DC input (sensors) on XO-4
 Reporter:  dsd     |                 Owner:               
     Type:  defect  |                Status:  new          
 Priority:  high    |             Milestone:  13.1.0       
Component:  kernel  |               Version:  not specified
 Keywords:          |           Next_action:  never set    
 Verified:  0       |   Deployment_affected:               
Blockedby:          |              Blocking:               
 Sam reports:

 I would appreciate if someone in Twine could check the "DC Input Bias" and
 "DC Mode Enable" controls.  I see no change in open circuit voltage
 toggling the DC Input Bias controls, with the Right mic channel not
 showing any notable voltage (~.5V compared to 2.5V on the left channel) at
 all.  When enabling DC Mode the open circuit voltage jumps up to 1.5V on
 the right channel but stays at 2.6V on the left.  The right channel
 voltage has to be bled off to get back to 0.5V after DC mode is disabled.

 I seem to recall something similar with XO-1.75 testing.  But all I have a
 DMM here to check things with and no resistors to load the mic circuits

 If someone could use a variable voltage generator to check the DC input
 range I would also appropriate that as well.

 Walter, can you help us with sensor testing on XO-4?

Ticket URL: <http://dev.laptop.org/ticket/12548>
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