#10048 NORM Not Tri: Red battery LED double-flashes on power-on or reboot

[Zarro Boogs per Child]

#10048: Red battery LED double-flashes on power-on or reboot
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           Reporter:  wmb at firmworks.com  |       Owner:  wad          
               Type:  defect             |      Status:  closed       
           Priority:  normal             |   Milestone:  Not Triaged  
          Component:  hardware           |     Version:  not specified
         Resolution:  fixed              |    Keywords:               
        Next_action:  never set          |    Verified:  0            
Deployment_affected:                     |   Blockedby:               
           Blocking:                     |  
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Changes (by wad):

  * status:  new => closed
  * resolution:  => fixed


Comment:

 I noticed that the clamp doesn't actually hold +3.3V at 0V during the
 power-up.  PR31 had the correct 22 ohm value.   I swapped PQ6, with no
 effect.

 I decreased PR31 to 11 ohms, and it improved the situation (now it almost
 always booted with a serial port attached.)

 I then decreased PR31 to 4.7 ohms, and it always boots with a serial port
 attached.   I am running it overnight (constantly rebooting) without a
 serial port to see if it ever does the "double boot" that Richard first
 noticed.

 Mitch reduced PR31 to 11 ohms on his failing laptop, and it also started
 working normally.

 I suspect that for some reason there is increased sensitivity to residual
 voltage on +3.3V in some VX855s, or increased leakage from +3.3VSUS to
 +3.3V ?

 For production, we are changing PR31 to be 10 ohms.

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Ticket URL: <http://dev.laptop.org/ticket/10048#comment:6>
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