Hello. I recently acquired a samsung 710v monitor that had a broken lcd, but the CCFL backlight was still OK. Out comes the screwdrivers then.
From this haul I obtained a really rather nice looking power suppy / inverter board (pwi1704SG(A) fact fans!) It gives handy outputs of 5V and 13V DC and 800V AC. Nice.
The problem is it only powers up when it is connected to the main board from the monitor, which works fine but it will shut down after a certain time and I would like to bypass this and turn the supply on from the Arduino directly.
The connector for the psu has 5 sections, BL_EN (Backlight enable, this goes to +4.2V when the panel is on) ADJ_BL (backlight brightness adjustment. I measured this at 110mV when active, I would also like to run this from the arduino. I wonder if a pwm signal would work?) also +5v, GND, +13V to supply the main board.
I built a simple circuit with a regulator and some voltage dividers to provide the same voltages as I measured but I can't seem to get it to activate the psu. When the BL_EN pin alone is pulled high the ccfl will flash on and off at what I estimate to be about 3 or 4 Hz, with the 100mV applied to the ADJ_BL pin at the same time I just get one short flash. tweaking this has no apparent effect.
I know that if I play with this thing for too long it is only a matter of time before I do something daft like drop a screwdriver across an inverter or forget to discharge that dirty great capacitor before I pick up the board, so any help from any LCD monitor gurus would be appreciated.
Thanks.