#10999 NORM Not Tri: 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:  Not Triaged
          Component:  hardware  |     Version:  1.75-A2    
         Resolution:            |    Keywords:             
        Next_action:  diagnose  |    Verified:  0          
Deployment_affected:            |   Blockedby:             
           Blocking:            |  
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Comment(by wad):

 Interesting result --- wiring up Vdd to a voltage divider tied to +3.3VSUS
 fixed the problem.   This doesn't sound interesting, as +3.3VSUS is not
 turned off when the laptop is powered off, but removing all power from the
 motherboard (forcing the IDT1338 to switch to the Vbat input) didn't
 trigger the problem.

 I believe the problem is due to the power-off waveform of Vdd.   I would
 note that the registers of the IDT1338 always report the amount of time
 since the last power-off!

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Ticket URL: <http://dev.laptop.org/ticket/10999#comment:8>
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