#10999 NORM 1.75-ha: XO-1.75 A3 idt1338 chip loses oscillator over laptop power cycle

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#10999: XO-1.75 A3 idt1338 chip loses oscillator over laptop power cycle
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           Reporter:  Quozl          |       Owner:  wad          
               Type:  defect         |      Status:  assigned     
           Priority:  normal         |   Milestone:  1.75-hardware
          Component:  hardware       |     Version:  1.75-A2      
         Resolution:                 |    Keywords:               
        Next_action:  test in build  |    Verified:  0            
Deployment_affected:                 |   Blockedby:               
           Blocking:                 |  
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Changes (by wad):

  * next_action:  diagnose => test in build


Comment:

 The data sheet is off by a little bit, as the minimum fall-time is greater
 than 300 uS.  But using a fall time of 760 uS works.   Tested on two
 laptops so far.

 Waveforms are at: http://dev.laptop.org/~wad/10999/

 The ECO is to replace R29 with a 330 ohm resistor, and place a 10 uF, 6.3V
 cap in parallel with C227.

-- 
Ticket URL: <http://dev.laptop.org/ticket/10999#comment:15>
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