Charlieplexed lighthouse version 2 PCBs have arrived

A long exposure makes it look quite funky

My version two charlieplexed lighthouse circuit PCBs (charliediscs) have arrived back from the Seeedstudio’s fab. I used the same deal as for my last boards, this time it took around 3 weeks in total.  That’s pretty good for 20USD!

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Updated code for simple PWM LED controller

I’ve updated the code to my LED strip driver and included a few new features.

Here’s a quick demo video.
[UPDATE 7 Mar 2011] Added input/output graph plus link to download LUT calc excel file.
[UPDATE : DEC 6 2010] I’ve had some proper PCB’s made for this circuit. More info here.

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Simple PWM control for LED strip

I have been playing around with building a lamp for my desk using a LED strip and constant current driver that I bought from Deal Extreme a while ago combined with a PIC12f683 to provide variable brightness via Pulse Width Modulation (PWM).

The demo using a plain old green LED as the output.

[UPDATE OCT 20 2010] I’ve updated the firmware for this project to include new features. More info and firmware download here.

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Little flashing lights

pict0125.jpgI was thinking the other day about LEGO (as you do) and remembering some of the things I used to build and some of the parts I used to have (and fight over with my sister)

I remember that my younger brother had a police set that had flashing lights and sound which was pretty cool and I started to think if I could make something similar using LEDs and a PIC.

The parts my brother had were these 1×4 flashing light block that came from this police truck set.

I had a look around the web and found some quite cool possibilities such as this modern looking light stalk but what I particularly want to create is a revolving multicolour beacon like you see on top of police cars.

I don’t want to get into physically revolving a reflector around a light source like in real life, this could prove to be a pain and also pretty fragile. Instead I want to use multiple LEDs arranged in an outward facing star and pulse them on and off in sequential order using the PIC.

The problem that immediately springs to mind is size, a whole bunch of LED, a PIC and associated circuitry is going to take up space, certainly more than the 1×4 block I initially thought of.

But by using SMD components and a bit of creative thinking I think I can get something working pretty well quite easily.

Read on to see how I get on.