#2182 BLOC Trial-2: Plugging in an XO with a low battery causes immediate poweroff and EC lockup

[Zarro Boogs per Child]

#2182: Plugging in an XO with a low battery causes immediate poweroff and EC
lockup
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  Reporter:  cscott    |       Owner:  gary   
      Type:  defect    |      Status:  new    
  Priority:  blocker   |   Milestone:  Trial-2
 Component:  hardware  |     Version:         
Resolution:            |    Keywords:         
  Verified:  0         |  
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Comment (by Terry Su):

 Kenl,

 So we final solution for fix ticket #2182

 1. R269 wire to VA2.

 2. Reserve a capacitor in parallel with R270. à Populate or Depopulate in
 C stage?

 3. Remove D1.

 4. Change R269 and R270 value to 1M and 158K.


 John,

 Above is our conclusion for ticket # 2182, would you have else concern ?


 Best Regards,

 Terry Su

 Quanta Computer Inc.

 EPBU R&D H/W

 TEL: +886-3-3272345 ext. 15280

 FAX:+886-3-328-5048


 --------------------------------------------------------------------------------

 From: kenl Lin (林世堅)
 Sent: Friday, July 20, 2007 2:58 PM
 To: Terry Su (蘇泰利)
 Cc: 'richard at laptop.org'; Arnold Kao (高顯宗); 'John Watlington'
 Subject: RE: Low Battery


 Hi Terry,

 If change the net of R269 from VA1 to VA2 can solve system shutdown issue.
 But the resistor value of R269 and R270 need to change to 1M-ohm and 158K-
 ohm to avoid leakage current and D1 also can remove it.


 Best Regards !

 Ken Lin

 Quanta Computer Inc.

 NB5 Research & Development System & Electronics

 Tel: (03)3272345 # 11549

 Address: 211, Wen Hwa 2nd Rd,Kuei Shan Hsiang,Tao Yuan 33377, Taiwan, ROC.


 --------------------------------------------------------------------------------

 From: Terry Su (蘇泰利)
 Sent: Friday, July 20, 2007 12:50 PM
 To: kenl Lin (林世堅)
 Cc: richard at laptop.org; Arnold Kao (高顯宗); John Watlington
 Subject: RE: Low Battery

 Kenl,

 Could you reply John mail about power circuit change ?

 moving the top of R269 to VA2 instead of VA1 ?

 or adding a capacitor in parallel with R270 ?


 Best Regards,
 Terry Su

 Quanta Computer Inc.
 EPBU R&D H/W
 TEL: +886-3-3272345 ext. 15280
 FAX:+886-3-328-5048
 -----Original Message-----
 From: John Watlington [mailto:wad at laptop.org]
 Sent: Friday, July 20, 2007 12:37 PM
 To: Terry Su (蘇泰利)
 Cc: John Watlington; richard at laptop.org; Arnold Kao (高顯宗)
 Subject: Re: Low Battery

 How about moving the top of R269 to VA2 instead of VA1 ?
 or adding a capacitor in parallel with R270 ?

 John

 On Jul 20, 2007, at 12:01 AM, <Terry.Su at quantatw.com> wrote:

 > John,

 > We can replicate it and our power team feedback the cause from Q34
 > soft start circuit cause AC/DC switch VIN have drop to under 5V.
 > The U65 LDO detect VIN fail then assert OVR to EC reset, so system
 > shutdown.They tried remove C324 this symptom was disappear, but we still
 > check this solution have another side effect.

 > Best Regards,
 > Terry Su
 > Quanta Computer Inc.
 > EPBU R&D H/W
 > TEL: +886-3-3272345 ext. 15280
 > FAX:+886-3-328-5048

 > -----Original Message-----
 > From: John Watlington [mailto:wad at laptop.org]
 > Sent: Friday, July 20, 2007 11:51 AM
 > To: Terry Su (蘇泰利)
 > Cc: John Watlington; Richard Smith; Arnold Kao (高顯宗)
 > Subject: Low Battery

 > Any progress on the low battery ?  http://dev.laptop.org/ticket/2182
 > Have you been able to replicate it ?   I haven't, although I see the
 > same effect you do when trying. ACOK# has a very strange behavior. I
 didn't
 > have time to take a look at the input, but I wonder if this has to do
 with
 > particular power adapters not reacting well to the sudden change in
 current when
 > they are plugged in.More bulk capacitance needed on the input  ?

 > John

-- 
Ticket URL: <https://dev.laptop.org/ticket/2182#comment:8>
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