In need for Acer 8930 ccfl inverter's pinout TBD489NR

sv1dkk
sv1dkk Member Posts: 1 New User

Hi to all,

I have backlight problems with my 8930 Acer laptop, nothing can be seen on the screen, where when connected to any external display (VGA/HDMI) works just fine. The laptop, therefore is in perfect working condition apart from the backlight of its screen. The video feeds the monitor and besides its darkness should you flash a light on top of the screen you can still see the desktop images. I've tried just about everything (Fn keys, drivers, reinstalling windows). I've removed the top bezel and looked for a lid switch. Nothing. (might be magnetic, I don't know but no reed of hall -effect switch could be seen). Then I thought it might be a defective inverter and so I had it replaced with a new one. No success. The backlight still won't turn on. I've checked the ccfl tubes with another inverter and both they work just fine. The only thing remains to check if the backlight enable and brightness voltages reach the inverter or not. Unfortunately, I have no documentation regarding the inverter's pcb input pinouts. Reverse engineering doesn't work 'cause the IC's datasheets cannot be found. (The following picture is borrowed from the web)

If anyone has any information on the pin identification of the TBD489NR 10-pin dual lamp inverter it would certainly be great help in figuring out what and where the problem is. Thank you in advance.