Ralph Landry wrote:

> I'm looking for suggestions on a chip that can do a triangle wave
> generation.  I have an application where I want to ramp up and down a 6
> to 12v lamp.  ie slowly on to full bright, and then back down in an
> endless loop.

Why a triangle wave? How about a square wave of varying duty
cycle. You could either use a 16C63 which has a hardware PWM
or a .90 cent 16C505 and do the PWM in software. So how about
this:

16C505 doing software PWM with the internal osc    .90
A NPN open collector transistor to drive the light        .10
A bypass cap                                                            .05
A base resistor for the NPN transistor                        .01
A 5 Volt regulator for the PIC                                    .15

So your looking at about $1.41 in parts plus your time to write
the routine.

-Jeff King
Aero Data Systems