50-3 bootup when cold

When using 50-3 parts half of my boards won’t bootup if the processor chips are cold when power is applied (or when freeze spray is applied), but bootup fine once they are warm. Has anyone seen this? What could I be doing wrong? (My architecture is quite similar to the NS reference design). I have not seen this on my old boards with 50-1 parts.

I’ve seen similar teperature related issues on custom board, whch ended up being a desin/component placement problem. You can request a design review done by Netsilicon