Hi!

Actually, it sounds more like they blew the design by having too
much input voltage for the output voltage and current.

The regulator is supplied with 25 volts. While I hadn't really looked
at the curves and figures, what they are doing did not sit well with
me from the outset. Why ask the regulator to do that much work?

But I would think that adding a bit of series
resistance to the input side and letting some of the waste
heat go away there would go a long way towards extending the
life of the regulator package.

I had not thought of this and might just sit down and do the math to
see what I'd need. What I do will depend upon whether or not there is
room to put something in place without going to extremes.

William