hi im no stranger to these and its almost always the backlight leds
but not this time ive stripped down and tested all leds and they are all good .
the psu comes out of sby and sound is present the 12v and 16v supplies are all good but the backlight feeds are only 3volt ,
this has two chains of leds and two plugs feeding
when i unplug the feeds even with peak hold meter theres only 3v the two fets ca5b3d that supply the tx test ok,
and i now suspect the surface mounted driver ic msc lx 27901 id ,i wonder
does it contain a comparitor cct that monitors the two strings of leds ?
and if the two current demands of the strings arnt the same then it switches off the fets ?
any ideas please
but not this time ive stripped down and tested all leds and they are all good .
the psu comes out of sby and sound is present the 12v and 16v supplies are all good but the backlight feeds are only 3volt ,
this has two chains of leds and two plugs feeding
when i unplug the feeds even with peak hold meter theres only 3v the two fets ca5b3d that supply the tx test ok,
and i now suspect the surface mounted driver ic msc lx 27901 id ,i wonder
does it contain a comparitor cct that monitors the two strings of leds ?
and if the two current demands of the strings arnt the same then it switches off the fets ?
any ideas please
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