Hi-
I'm driving a piece of LCD glass, no backlight, which draws 0.1uA measured with multimeter.
circuit (NPN.jpg) is attached. The input is a 5V PWM signal. The output at the collector is ground, no switching. +V is +12V, but I've tried higher voltages.
When I use a PNP, same input, the output is the same PWM signal but at about 1V.
Why isn't the PWM signal duplicating at the collector?
The LCD glass must be the issue (I do not have a spec sheet), as using an LED gives a similar signal at collector as base.
Thanks in advance.
I'm driving a piece of LCD glass, no backlight, which draws 0.1uA measured with multimeter.
circuit (NPN.jpg) is attached. The input is a 5V PWM signal. The output at the collector is ground, no switching. +V is +12V, but I've tried higher voltages.
When I use a PNP, same input, the output is the same PWM signal but at about 1V.
Why isn't the PWM signal duplicating at the collector?
The LCD glass must be the issue (I do not have a spec sheet), as using an LED gives a similar signal at collector as base.
Thanks in advance.
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