[Rick Dall]

Thanks Neeraj.

Re. your questions,

1. We’ve found a newly manufactured batch of boards for which ~ 40% intermittently fail to boot. I’ve examined some non failing samples and find a similar glitch on SYS_VOUT but not such that the boot failure occurs. Boot failures seem to be confined to modules with date code 2307. Other date  codes in use are 2239 and 2104.

2. Device is being supplied via input VIN_BAT directly from a Li-Ion cell in range 3.3 to 4.2VDC.

3. I have looked for glitches on the input side (VIN_BAT) but found none

Will continue to study the problem along with the notes you’ve suggested.

 

 

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