My new super interior light

PeeJay · Post by **PeeJay** » Fri Mar 02, 2007 11:13 pm

Got sick of the stupid dull interior light so I made another. It consists of 8 sets of 3 50,000mcd leds with a 47 ohm resistor in series. If I made another I would change the resistors to 42 ohm (perhaps even 39) and angle some of the LEDs outwards to spread the beam a bit more.

Needless to say, I can now read my map in the dark:)

Lapsed · Post by **Lapsed** » Fri Mar 02, 2007 11:26 pm

very nice. was thinking tonight about upgrading mine. do you have a pic of the back?

steptoe · Post by **steptoe** » Sat Mar 03, 2007 3:06 am

a bit of smart circuitry next to time out in case door not shut properly and fade out when door is shut perhaps ? nice work

fredsub · Post by **fredsub** » Sat Mar 03, 2007 6:38 am

good job!

but be very careful with what voltage range you expect to use it with,
i'm guessing these are 3.3V(forward) 30mA, so even with 47ohm you are overdriving them if your system voltage is 13.8v, and car voltage is notorious for spikes into 14v+, which the leds are very sensitive to...ie they shine bright for an instance....then.....oh damn...

my 2c, is that there much safer being driven from a small switching supply in pairs....the dilemma is fitting it in the space.....

BaronVonChickenPants · Post by **BaronVonChickenPants** » Sat Mar 03, 2007 7:14 am

As far as a fade out effect all you would need is a capacitor in series.

Jordan.

PeeJay · Post by **PeeJay** » Sat Mar 03, 2007 9:36 am

The Vf is 3.4 - 3.8v, current I think is 30mA. I set the voltage for when the car is off because that is when the light is on the most. Even if I shorten the life from 100,000 hrs to 5,000 hours I don't think I'd notice. Originly I had 4 in series with no resistor, but they were much too dull so I had to change it.

I was going to make a remote-controlled brightness control but I've only got 40pin microcontrollers so I didn't bother.

The capacitor idea is good! Will go do that now.

Didn't take a photo of the bottom but looks much the same as this:
http://led.linear1.org/led.wiz?VS=12.2& ... ID=30&N=24

Subafury · Post by **Subafury** » Sat Mar 03, 2007 10:22 am

thats a pretty smart idea- ive been wanting to do something like that for ages-or even just fix my light as it hasnt been working ever.

Subyroo · Post by **Subyroo** » Tue Mar 06, 2007 10:37 pm

I've got a 4 x Led in my centre cab light & driver's side map light and the passenger side got a 6 x Led and the rear cargo area also got a 4 x Led bulb.

waggaclint · Post by **waggaclint** » Tue Mar 06, 2007 10:48 pm

ive seen 12v household down lights used they are really bright the small ones about 5cm in dia..............

BaronVonChickenPants · Post by **BaronVonChickenPants** » Wed Mar 07, 2007 7:11 am

Geez if you left a door open they'd suck you battery dry in under an hour.

Jordan

Subyroo · Post by **Subyroo** » Thu Mar 08, 2007 8:13 pm

BaronVonChickenPants wrote:Geez if you left a door open they'd suck you battery dry in under an hour.

Jordan

You talking to Peejay or me Jordan?

PeeJay · Post by **PeeJay** » Thu Mar 08, 2007 8:30 pm

I was going to install a 12v 50w downlight in my last car, but never got around to it. Then I was going to install a 5w Luxeon led.

I've got 2 3w Luxeon leds here and I've ordered some 8 pin micros so we'll see what they form into in a few weeks

BaronVonChickenPants · Post by **BaronVonChickenPants** » Thu Mar 08, 2007 8:50 pm

I was actually referring to what waggaclint said about the 12v halogen.

Jordan.

Post by **Alex** » Thu Mar 08, 2007 9:04 pm

my big interior light(twin flouro tubes)

and my smaller front area light(one also in the boot), note the burnt plastic cos i put massive globes in it..

alex