OK - thanks
Where to start with micro-controllers? I know zero about micro-controllers?
As recommended above the PIC10F320 would suit this PWM.
I have dug around the net and this website - but a simple point to start and get a feel for micro-controllers would be great.
Angus
Angus.. how much would you like to learn about micro controllers?
For sake of argument lets consider them to be the same (Please don't flame me)
PIC is a great robust product and will suit your need for years to come, but you may find development tools to be a little bit harder to grasp. I consider this to be a much more professional approach
Items like Arduino have some additional tools available but additional tools usually mean bloatware.
They are incredibly easy to get running in a few minutes out of the box and many of the devices can be managed via a standard USB mini connector.
Which direction you head is up to you, I would recommend either.
You can get minute microcontrollers like Atmel's Attiny 85.
http://www.atmel.ca/devices/ATTINY85.aspx
You can go with larger board like the Arduino Mega.
http://arduino.cc/en/Main/arduinoBoardMega
There are tons of resources available for any path you'd like to take.
http://www.microchipdirect.com/productsearch.aspx?Keywords=dv164120
Discrete components can be used as well... usually a sawtooth or triangle wave is generated and fed into a comparator. The other comparator input is usually a potentiometer. As the potentiometer goes up, the duty cycle of the PWM output decreases.
Here is some info.. you will need to pick and choose, it's not perfect.
http://www.ibiblio.org/kuphaldt/electricCircuits/Semi/SEMI_11.html
