"Michael" wrote in message
ng.com...
I have a dell 1504FP (LCD monitor). The backlight doesnt work for a period
of time.

On close examination with a scope on the PSU board, BIT3105 (lamp
controller
IC) is getting confused. It has several pins to do with OLP (open lamp
indicator)- basically the chip switches itself off if it thinks one of the
lamps is open circuit. The lamps are definitely all working. I can
recreate
the problem by disconnecting any one lamp.

The OLP circuit waits for a cap to reach 2.5v before monitoring- if I
drain
that cap, the monitor works.

Could someone look at the BIT3105 data sheet and tell me how to disable
the
OLP circuitry- I dont care if it shortens my monitor life. Please help.

Thanks in advance.

Michael.



Perhaps a resistor across that capacitor would make it less sensitive? How
are you draining it? Just shorting across it?