#10429 NORM Future : XO-1.75 turns on power light and nothing else

[Zarro Boogs per Child]

#10429: XO-1.75 turns on power light and nothing else
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           Reporter:  wad       |       Owner:  wad           
               Type:  defect    |      Status:  new           
           Priority:  normal    |   Milestone:  Future Release
          Component:  hardware  |     Version:  1.75-A1       
         Resolution:            |    Keywords:  XO-1.75       
        Next_action:  design    |    Verified:  0             
Deployment_affected:            |   Blockedby:                
           Blocking:            |  
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Comment(by wad):

 The SPI Flash on the A1 motherboard is smaller than was expected by the
 layout team, and as a result it requires several solder bridges to mount.
 Upon examination, one of these appeared to have developed a hairline
 crack.

 Reflowing the solder on the pads, especially with the addition of some
 solder containing lead, corrects the situation.   It is recommended as a
 first test on the A1 motherboards.

 In future motherboards, we will strive for: 1) correct sizing of the pads
 for the part, plus 2) enough additional pad to make multiple reworks
 stable, plus 3) connections to the pad through pad vias, not traces, to
 minimize pad tearing.

 4) Definitely no routing of signals through the pads, as was done on the
 SPI programming header for the EC SPI Flash!   When these pads rip off, it
 kills a board (no EC booting.)

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Ticket URL: <http://dev.laptop.org/ticket/10429#comment:1>
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