On Mon, 18 Feb 2002, Olin Lathrop wrote:

> One thing to watch out for is the startup surge.  Since the fillament
> temperature changes drastically from off to on, so does its resistance.
> When first turned on, an incandescent bulb can draw 10x or more of its
> steady state on current for a short time.  The fillaments hate that, which
> is why soft starting extends life, but also why you have to design the
> switching circuit carefully.

Good to have you back, Olin, and thanks for responding.  So let's assume
I'm going to use a PWM rate of a couple hundred Hz.  Would something
simple, like going from 0/256 to 256/256 PWM duty cycle over a period of a
second or so, be sufficient, or am I missing something?

Dale

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