LED backlights (from laptop displays.)

[westfw]

I have this LED backlight PCB extracted from a broken display, but I can't get it to light up at all. Does anyone have any clues?

The connector has 6 contacts; the top two merge into a single track, leaving 5 actual connections to the PCB. I assumed the double track was "Gnd", but ... no blips with either polarity of voltage on the other traces (current-limited "lab" power supply at various voltages.)

[Twizted]

I have this LED backlight PCB extracted from a broken display, but I can't get it to light up at all. Does anyone have any clues?

The connector has 6 contacts; the top two merge into a single track, leaving 5 actual connections to the PCB. I assumed the double track was "Gnd", but ... no blips with either polarity of voltage on the other traces (current-limited "lab" power supply at various voltages.)

I have an identical backlight strip from an LG 15.6" laptop LCD display. I was going to try to use the panel to do a backlight sign but I ended up having to take it apart to get the LED strip out so I could start working on figuring out the pinout for it. I finally got around to taking it apart today and I've been examining it but because of the thick white coating over the PCB its very hard to see what is going on... I did snap a few pics with my USB microscope attached below.. I'm debating how best to get into this more so I can better tell what leads are going where...

[Twizted]

Just took a few more shots... because, I just broke mine lol... I was trying to clear some of the white screen off of it and the paper towel snagged and 90°'s later... yeah... anyway, here are a few shots of the LED's and how they are soldered on the board that may help you in your efforts...

[Twizted]

Sorry for the triple post but... WOW, these things are super bright.. still seeing spots ... I took a single LED I pulled for those pics and hooked it up to 3.3v and wow... wish I has not broken the board now

hopefully I'll see another come through the shop before to long... We get laptops in all the time with broken screens... just a matter of time...

[Twizted]

Got another display in today. Trying to make out how to power it. There are 9 pins on the ribbon, three of those are tied together on both the PCB and the ribbon itself. the other six go to an IC (with resistors in-line). If I could find information on the IC it would help in figuring this out but I cant seem to find anything on the IC...

The IC is printed with the following...

9956B
MRL . 1F
0915A

Anyway, I'll try to not break this one lol... Hope we can figure these out because these would be awesome to use in come projects..

[Twizted]

I have scavenged several more LED strips from LCD's that have came through the shop and I've gotten a few that are on flexible PCB which are -not- covered with silkscreen to protect the traces/design.... I pinned one out and it looks like its pretty simple, at least on that one.... I've attached a schematic to show how its wired up.

I've also found an IC that should work for lighting these strips up which is available from Digikey.

Intersil 6-Channel SMBus/I2C or PWM Dimming LED Driver with Phase Shift Control
ISL97671A <- PDF
ISL97671A on Digikey

I like the fact that it has I2C control for dimming as well as device control/status but at the same time I would totally be over my head for making a program sketch to communicate with it. The PDF has some pretty good information though regarding communication. I just don't know enough about I2C...

If someone was seriously interested in helping figure out how to use this Intersil IC with Arduino and how to get all the control and status feedback working I could send you a LED strip to test with...