This startup issue looks like that described in the attached note as symptom no
2. The solution is to reduce the capacitive load and/or add a resistive load
to avoid restart issues, as shown in figure 1. There is a revision that is
available through distribution, with data code 11/28 or later.
Please see the symptoms in the attached document
This applies to all ADuM52xx and All ADuM64xx parts
There is a new die available which was introduced mid 2011 - please see