#1476 NORM BTest-4: microphone circuits never powered down

[Zarro Boogs per Child]

#1476: microphone circuits never powered down
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  Reporter:  dwmw2   |       Owner:  wad      
      Type:  defect  |      Status:  assigned 
  Priority:  normal  |   Milestone:  BTest-4  
 Component:  kernel  |     Version:  Build 406
Resolution:          |    Keywords:  power    
  Verified:  0       |  
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Changes (by wad):

  * owner:  dilinger => wad
  * status:  new => assigned
  * verified:  => 0

Comment:

 I've got a fix wired into B3 Cuy (in cjb's hands in Cambridge).  It
 eliminates all blinking of the LED as it transitions into and out of
 suspend mode.

 The basic idea is to filter the control signal to eliminate the minor
 glitch when going into suspend, along with another circuit with a longer
 time period which ensures that the LED is kept off for the first N
 milliseconds after +3.3V is turned on.

 I still need a good estimate on the worst case value for N from the
 firmware team, but that adjusting that value is just a BOM change.

 I will forward to Quanta for their usual review and cost reduction.  I'm
 leaving the ticket open to ensure that we get the hardware fix into B4.

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Ticket URL: <http://dev.laptop.org/ticket/1476#comment:5>
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