Chosen Solution
Hi, can I get some help in finding the schematics and the Led driver on my MacBook Air ? The fuse is good but still no backlight on the device. The whole display assembly is replaced. S/n C02J52DEDRVG Best regards, Vlad Update Hi oldturkey03,
I really appreciate your effort in helping out a stranger. The MacBook air was declared dead after a liquid spill and out of warranty. Now the MacBook works on an external display. After reading a bit on the net, I found the fuse which is marked with a “P” and if I measure it with an volt meter and set it to conductivity (diode sound measurement) it says that the fuse is ok. I’ll try to attach the images from the MB and I would be grateful if you can help me find out the led driver location and the filter location. Thanks in advance, Vlado
Update Here is the
Update
Vlado, two things you do want to check besides your fuse. The backlight driver is a TI LP8550 and is reference designator U9701, get the datasheet from here , but also check your backlight driver input current sense filter circuit. Here, the main component is INA211, reference designator U5490. The data sheet is available from here If it does not sense any current coming in, it may not tell the LED driver to work. Hope this helps, good luck.
Update Vlado, attached are the images that show the location of the two parts. Sorry had to mess with your images, but I need a bit higher resolution. Hope this is what you are looking for.
Further Update Vlado, good job on the enlarged image. I am not sure which component you were referring to, I listed the IC’s so you can find the U5490 easier. U4600 is part of your USB Port Power Switch. U9000 is a The FPF1007/8/9 are low RDS P-Channel MOSFET load switch and has to do with your LVDS LCD connector, but not the backlight
One More Update Vlado, not exactly sure which component you are referring to, but I suspect you mean reference designator L9004 which is a FILTER CHIP 120 OHM 1.5A 0402 and is available from places like Digikey.com part number 490-4004-1-ND.
