Dave's stair lighting project

[Paul Beard]

Dave, are you on this google group?

I was thinking about your stair lighting project idea. We said at the meet today that 14 pwm-capable outputs would be needed from the Arduino to fade the led strips. But the Uno only has 6. Well, actually when you think about it, only one strip would be fading up or down at any instant in time. The other 13 would be full on or off. So we could write a function in the sketch to fade any output up or down, even if it is not one of the pwm-capable outputs (using digitalWrite and delayMicroseconds functions). Problem solved.

As for driving the strips, how much current do you estimate each individual strip would draw? Depending on that, possibly 2 ULN2003 chips or 14 BC337 transistors could be used.

Still need to think about those sensors... how about a couple of those PIR sensor modules?

Pail

[Paul Beard]

http://www.ebay.co.uk/itm/Pyroelectric-IR-Infrared-PIR-Motion-Sensor-Detector-Module-HC-SR501-Arduino-/360924972153?pt=UK_BOI_Industrial_Supply_Security_Equipment_ET&hash=item5408ce0479

[Paul Beard]

Second thoughts about those transistors I suggested. Each strip will be about 1M? That's 1A current each. So I am now thinking 14 logic-level power FETs. Probably around 50p each.

http://www.rapidonline.com/electronic-components/stp36nf06l-mosfet-logic-n-60v-30a-47-0552