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View Full Version : Pics of new style LED taillight and turn signals


mohrds
06-23-2005, 01:17 PM
Well, I finally got around to getting some comparson pics of the new style LED taillights I made from scratch.

You can view them in my locker http://www.subaru-svx.net/photos/user.php?mohrds|27419

A couple of points.
Each of the four Stop/Tail light panels contains 78 LEDs
Yes I know there are three dead LEDs on the Driver's side iner and outer light panels. They will be fixed.
Each turn signal contains 20 LEDs
The Center LED panel was completly rebuilt using 56 new high-flux LEDs, new resistors and new diodes.
The side markers (which I forgot to take photos of) contain 3 LEDs.

Cost of components (minus circuit boards) is $262 plus shipping.

Building the panels using stock Radio shack perforated breadboard was a total pain in the butt. I designed a new dual sided style to be custom fabricated, but it adds about $150 onto the cost.

Attached are the parts list and board schematic in Acrobat format.

Doug

Earthworm
06-23-2005, 02:03 PM
Looks awesome...kinda like a new G35.

So when do you start taking orders? :D

KCROGUEDOG
06-23-2005, 02:05 PM
congrats those are nice i really like. i might have to do the swap later when i run out of stuff to work on. can u get a pic of the turn signals blinking. throw on the hazards and try to time it right.

CigarJohnny
06-23-2005, 04:11 PM
Pretty nice, Doug! Great job. :cool:

n00b on demand
06-23-2005, 04:30 PM
Holy crap those look awesome!!....great job man :)

black beast
06-23-2005, 04:45 PM
If you start selling them, and I come across some money, I would buy some. You should make a reverse light led too.

mohrds
06-23-2005, 04:47 PM
Looks awesome...kinda like a new G35.

So when do you start taking orders? :D

Well, lets see... About $275 for LEDs shipped, about $150 for circuit boards, then there is the issue of my time hand soldering in 576 individual components. $50 in electrical epoxy (to avoid dead rows like I have) Modifying the housings to accept the panels, etc.

So I should be able to start taking orders about mid 22nd century :D

Seriously, I can't imagine anyone on this board shelling out $500-600 for this conversion.

The next set I will do for the 5 speed, I will record step by step photos and instructions along with parts sources for anyone who wants to do it themselves.

Doug

AFBeefcake
06-23-2005, 04:49 PM
Nice job.
Do you blinker's still blink at the stock speed?

mohrds
06-23-2005, 04:52 PM
If you start selling them, and I come across some money, I would buy some. You should make a reverse light led too.


The reverse light was planned and was prototyped using the old CMHSL LEDs, but to buy enough clear LEDs to equal the light output of stock 1156 bulbs would be too expensive. Each backup light would need 182 LEDs in it and instead of being 50-60 cents each like the yellow and red cost, the clears are $2.04 each :eek:

Clear LEDs are still outrageously pricey.

mohrds
06-23-2005, 04:54 PM
Nice job.
Do you blinker's still blink at the stock speed?

Yes, but it required building a custom flasher. I wasn't about to drop $40 for a "LED Flasher" when I can build one for less than $5.

ensteele
06-23-2005, 06:26 PM
Those look great. To bad they are so expensive, or cheaper to put together. :)

SEA Sleeper
06-23-2005, 06:41 PM
Those will really confuse people who don't know what the SVX is. I'm sure w/ those they will think that the car is a new release.

Great work, those look very very nice.

NikFu S.
06-23-2005, 06:49 PM
Looks more knight ridery.

Melikes.

ThetaReactor
06-23-2005, 11:22 PM
Ultra spiffy.

Incidentally, what is the output of those LEDs? I'm guessing they look a bit more red in person, too...

SilverSpear
06-23-2005, 11:50 PM
Well, lets see... About $275 for LEDs shipped, about $150 for circuit boards, then there is the issue of my time hand soldering in 576 individual components. $50 in electrical epoxy (to avoid dead rows like I have) Modifying the housings to accept the panels, etc.

So I should be able to start taking orders about mid 22nd century :D

Seriously, I can't imagine anyone on this board shelling out $500-600 for this conversion.

The next set I will do for the 5 speed, I will record step by step photos and instructions along with parts sources for anyone who wants to do it themselves.

Doug

hehe, i am waiting. I want it, I want it, I want it, I want it, I want it................................................ .... oh boy

I can do the board over here very easily, i have some friends who work in electricity and stuff and they have a machine to do that board. still i need the leds, Doug: I need each of the parts specs and if you can send close pics of them for me what to look for...

Xcellent job buddy..

mohrds
06-24-2005, 07:14 AM
Ultra spiffy.

Incidentally, what is the output of those LEDs? I'm guessing they look a bit more red in person, too...

They are pure red. It is virtually impossible for an amatur photogropher to get a color correct picture of an LED.
Brake lights:
4-PIN Super Flux Red Lamp: 5,000 mcd
7.4mm x 7.4mm water clear package. High performance super flux led lamps, suitable for high pulse operation of up to 50mA. Unique conical radiaton pattern, wide surface area distribution. Ideal for backlighting outdoor signs, moving message boards, displays. Color: InGaAlP/GaP TS Red (630nm). Intensity: 5 cd (If=20mA). Total angle: 70 Deg.

Turn Signals:
4-PIN Super Flux Amber LED Lamp: 3,500 mcd
7.4mm x 7.4mm water clear package. High performance led lamps, suitable for high pulse operation of up to 50mA. Unique conical radiaton pattern, wide surface area distribution. Ideal for backlighting outdoor signs, moving message boards, displays. Color: InGaAlP/GaP TS amber (590nm). Intensity: 3.5 cd (If=20mA). Total angle: 70 Deg.

CMHSL:
Super Bright Red (60 Deg.): 3,000 mcd
T1 3/4 High flux LED lamps utilizing InGaAlP/GaP technology. Color: 630 nm TS red. Viewing angles: 60 Degrees. Water Clear lens. Solder leads without stand-off.

mohrds
06-24-2005, 07:18 AM
hehe, i am waiting. I want it, I want it, I want it, I want it, I want it................................................ .... oh boy

I can do the board over here very easily, i have some friends who work in electricity and stuff and they have a machine to do that board. still i need the leds, Doug: I need each of the parts specs and if you can send close pics of them for me what to look for...

Xcellent job buddy..

You can get all the specs and images at lc-led.com The individual part numbers are in the parts list attached to my first post.

I'd love to get your freinds to do a batch run of boards. The design is in ExpressPCB format http://www.expresspcb.com but I could re-create it in autocad or something if they need it in that format.

Doug

SilverSpear
06-24-2005, 07:54 AM
just an idea guys, i think you have junk yards in the states, right? and you do have damaged cars with led taillights, right?... so why don't someone go and get a bundle of broken led taillights and do the conversion without taking that expensive road... :confused: :confused:

AFBeefcake
06-24-2005, 08:55 AM
Yes, but it required building a custom flasher. I wasn't about to drop $40 for a "LED Flasher" when I can build one for less than $5.


How would one build one?

SSSVX
06-24-2005, 03:06 PM
LED lights are much brighter and faster for my observations.

It looks awesome, doug!

When I'm rich, I will consider about this improvement... :D

mohrds
06-24-2005, 03:24 PM
just an idea guys, i think you have junk yards in the states, right? and you do have damaged cars with led taillights, right?... so why don't someone go and get a bundle of broken led taillights and do the conversion without taking that expensive road... :confused: :confused:

Two reasons:
1. Salvage yards charge top dollar for taillights with LEDs in them
2. The LEDs and circuits are coated with a clear epoxy about 3mm thick to provide shock resistence. That stuff is virtually impossible to remove without destroying the components.

mohrds
06-24-2005, 03:59 PM
How would one build one?

I'll dig up the schematic and post it.

Tofu
06-25-2005, 03:52 AM
"Seriously, I can't imagine anyone on this board shelling out $500-600 for this conversion."

*cough* I would.........

ThetaReactor
06-25-2005, 08:59 AM
BG Micro has some excellent deals on LEDs, by the way...

http://www.bgmicro.com/pdf/page11.pdf

And I'm sure you've come across these monsters:

http://www.luxeonstar.com/

A friend of mine put in a blue one as the dome light on his Jetta. It was not something you wished to turn on without warning.

kuoh
06-25-2005, 02:30 PM
Great job on the build, but you can get almost identical LEDs at Digikey for about 1/2 the price and I'm not sure that you really need those extra diodes or the large power resistors. The single current limiting resistor for each 3 LED array should suffice I would think.

160-1625-ND 3375mcd $30.80/100 pcs (red slightly dimmer)
160-1631-ND 7500mcd $33.80/100 pcs (red much brighter)
160-1658-ND 3200mcd $27.60/100 pcs (red same)
160-1632-ND 4180mcd $33.80/100 pcs (amber same)

KuoH

mohrds
06-26-2005, 11:01 AM
Great job on the build, but you can get almost identical LEDs at Digikey for about 1/2 the price and I'm not sure that you really need those extra diodes or the large power resistors. The single current limiting resistor for each 3 LED array should suffice I would think.

160-1625-ND 3375mcd $30.80/100 pcs (red slightly dimmer)
160-1631-ND 7500mcd $33.80/100 pcs (red much brighter)
160-1658-ND 3200mcd $27.60/100 pcs (red same)
160-1632-ND 4180mcd $33.80/100 pcs (amber same)

KuoH

Great find!

The diodes are for keeping the tail/stop circuits isolated. I needed two for each circuit to keep the board layout as simple as possible. I went with those resistors because they were the same price as the smaller ones.

To keep the panel thin and pleasant looking, all the resistors/ diodes are on the back, only the LEDs are on the front side.

Please, I'm looking for any improvement ideas so keep 'em coming!

Doug

kuoh
06-26-2005, 11:56 AM
Ok, I see where I went wrong now. You're using the larger resistor to limit the brightness for the taillights and the brake lights bypasses it. Did you intentionally leave out the tail light resistor for the lower 3 rows of lights on the circuit board PDF?

Looking over the parts list, it appears that you've designed the LED current to be about 72ma@12.7V when the brake lights are activated. The spec sheet indicates the maximum forward DC current is 50ma and pulse current is 100ma. Since I see no PWM circuitry, I would suggest going up on the array resistors to dial the current down to below 50ma. 120 ohm resistors should work fine.

KuoH

The diodes are for keeping the tail/stop circuits isolated. I needed two for each circuit to keep the board layout as simple as possible. I went with those resistors because they were the same price as the smaller ones.

mohrds
06-26-2005, 07:46 PM
Ok, I see where I went wrong now. You're using the larger resistor to limit the brightness for the taillights and the brake lights bypasses it. Did you intentionally leave out the tail light resistor for the lower 3 rows of lights on the circuit board PDF?

Looking over the parts list, it appears that you've designed the LED current to be about 72ma@12.7V when the brake lights are activated. The spec sheet indicates the maximum forward DC current is 50ma and pulse current is 100ma. Since I see no PWM circuitry, I would suggest going up on the array resistors to dial the current down to below 50ma. 120 ohm resistors should work fine.

KuoH

I probably missed it (or got distracted) when creating the circuit.

I used this site http://ourworld.compuserve.com/homepages/Bill_Bowden/led.htm
and the specs from lc-led's website to find the resistors. It calculated 75 Ohm at 13 volts will give me 50mA. If it is wrong, then I'm probably in trouble :eek:

kuoh
06-26-2005, 08:38 PM
What values did you put into the form? With 3 LEDs at 2.2V each running 50ma on 13V system voltage, it comes up with 130 ohms. However, that form does not take into account the extra 0.7V dropped by the isolating diode.

The way to calculate the value of the current limiting resistor is to subtract the LED voltage(s) from system voltage, then divide by the desired LED current. With the values you're using now, you're exceeding maximum DC current by almost 50%, which will probably result in the LEDs failing much sooner than expected. It may be the reason that you already have one dead column, one of the LEDs might have already fried.

KuoH

mohrds
06-26-2005, 09:09 PM
What values did you put into the form? With 3 LEDs at 2.2V each running 50ma on 13V system voltage, it comes up with 130 ohms. However, that form does not take into account the extra 0.7V dropped by the isolating diode.

The way to calculate the value of the current limiting resistor is to subtract the LED voltage(s) from system voltage, then divide by the desired LED current. With the values you're using now, you're exceeding maximum DC current by almost 50%, which will probably result in the LEDs failing much sooner than expected. It may be the reason that you already have one dead column, one of the LEDs might have already fried.

KuoH

I did for the low end 2.2V each and 10.2 volts gives me 75 Ohm, on the max end, 3.1V and 13.2 Volts gives me 75 Ohm, so I should be good with voltages between 10.2 and 13.2

The "dead" leds aren't dead. If you tap them, they come back on. They just have bad solder joints somewhere.

kuoh
06-26-2005, 09:25 PM
The VF(typ) indicates the typical voltage drop across the LED, VF(max) indicates maximum voltage drop before damage occurs. With a current limiting resistor, an LED will operate at VF(typ) with the resistor dropping the rest of the system voltage. This means that you should calculate your current with an LED voltage of about 2.2V, though the ambers actually operate at 1.95V.

I wouldn't bother with calculating the values with a system voltage of 10.2V, since that is not a normal condition and you have more problems to worry about than the LEDs not being bright enough. I would use a low end of 11.5V and don't forget that the isolating diode drops an extra 0.7V, which is not factored in on that webform. You can comphensate for this by adding 0.7V to the system voltage when using their formula.

The problem in your current circuit is that at 13.2V, the LEDs are still dropping only 2.2V, not 3.1V as you're assuming. This means that you're actually running 79ma through each LED. If I were you, I would change out those resistors ASAP, as those are some expensive LEDs if you end up having to replace a bunch of them in the near future.

KuoH

Seraph
06-26-2005, 10:28 PM
Been busy at work. I still have to mail you the title for the SVX. ;) Now, it's my turn. :D

Seraph
06-26-2005, 10:29 PM
BG Micro has some excellent deals on LEDs, by the way...


And I'm sure you've come across these monsters:

http://www.luxeonstar.com/

A friend of mine put in a blue one as the dome light on his Jetta. It was not something you wished to turn on without warning.


Luxeonstars -- Yeah I know of them. They are the same ones the new Audis use for the front head lights. They are nice. Enough said without giving away too much.

Seraph
06-26-2005, 10:31 PM
just an idea guys, i think you have junk yards in the states, right? and you do have damaged cars with led taillights, right?... so why don't someone go and get a bundle of broken led taillights and do the conversion without taking that expensive road... :confused: :confused:


Because they are had to find (LED Junkers) and also, they are very exensive