On Tue, Apr 29, 2014 at 9:16 PM, James A. Markevitch <jam at magic.com> wrote:
  I am not intimately familiar with the KL10 schematics
yet.  Does it pass
 single-ended signals between power domains, or does it use differential
 for those?
 
There's a mix.  They use twisted pair differential for clocks and a few
such things, but the data lines and such are single-ended even across
domains.
Eric