Hi guys
I need help with this one.
When i turn it on it has no backlight, but with source connected image is visible with help of flashlight
.
So, 19V going to the mainboard are present, on/off pin is going from 0V to 2.8V when power button is pressed. DIM pin is 3.2V all the time.
I dissmanteled LCD to reach LED string. Measured one by one LED and they are all OK. From power supply to the strip is going 19V, 2 lines, each feeding 18 LEDs and it has 2 current sensing lines going back to LED driver OZ998B.
Q801 voltages with refference to GND are G:0V, D:19V, S:0V, does not change with pressing power button.
Same is happening with LEDs connected or disconnected, does not change anything.
Pins 8 and 10 of U801 on turning on goes from 0 to 6V.
The schematic is more or less this one, difference is 19V power supply and 2 led strips:
http://hsto.org/getpro/habr/post_ima...93e1b46374.gif
I need help with this one.
When i turn it on it has no backlight, but with source connected image is visible with help of flashlight
.So, 19V going to the mainboard are present, on/off pin is going from 0V to 2.8V when power button is pressed. DIM pin is 3.2V all the time.
I dissmanteled LCD to reach LED string. Measured one by one LED and they are all OK. From power supply to the strip is going 19V, 2 lines, each feeding 18 LEDs and it has 2 current sensing lines going back to LED driver OZ998B.
Q801 voltages with refference to GND are G:0V, D:19V, S:0V, does not change with pressing power button.
Same is happening with LEDs connected or disconnected, does not change anything.
Pins 8 and 10 of U801 on turning on goes from 0 to 6V.
The schematic is more or less this one, difference is 19V power supply and 2 led strips:
http://hsto.org/getpro/habr/post_ima...93e1b46374.gif
Attached Files
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