Any chance of some advice?
I need to design an LED dimming circuit to be used as a speedo backlight. I will need to have two inputs corresponding to "Dimmer" and "Brighter" and use a PWM output to the LEDs.
At university, I did a similar project using a 16F84 and the output derived from a simple count up or down. I am considering using the same for this project, but I am sure that there will be a more suitable PIC for this application. I've checked the Microchip website but the sheer number of types available is a bit daunting!

 

PIC16F877A. >>> PWM max. resolution is 10 bit
with 8 KB flash memory 40 pins

 

Pick one with internal PWM - the 16F628 (the 'modern' replacement for the antique 16F84) has a single PWM channel, and also an internal 4MHz oscillator. There are many others which would do the job, but that one should be familiar to you.

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Perhaps 40 pins is a bit of overkill for dimming an LED?.

__________________
PIC programmer software, and PIC Tutorials at:
http://www.winpicprog.co.uk

 

Thanks for your help, I'll give it a try

 

12F683 with one pwm channel, internall 8mhz osc and only 8 pins.

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The 12F683 is a great little chip. I use it in a number of compact designs. Not only does it have PWM, it also has 3 timers including a 16-bit one and one with a period register, interrupts, a comparator, A/D converter, and interrupt on change pins.

You can get them for about $1 in quantities of 25 from Mouser.