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SiriusHardware · 10th Jun 2019, 12:06 am

Is it possible that the display is not actually drawing excess current, but the 12V supply to it is collapsing when it has a load because it can no longer supply any significant current?

If you have a resistance meter, what resistance do you see between the +12V in terminal of the display and 0V/GND of the display when it is disconnected from the circuit which powers it?

Try running something else, maybe just a resistor with the right value, on the 12V supply - presumably 12VDC? - which normally feeds the display. (disconnect the display). See if it holds up at 12V when it is supplying a load.

10th Jun 2019, 12:06 am	#2
SiriusHardware Dekatron Join Date: Aug 2011 Location: Newcastle, Tyne and Wear, UK. Posts: 11,560	Re: Sharp EL displays LJ640U80 Is it possible that the display is not actually drawing excess current, but the 12V supply to it is collapsing when it has a load because it can no longer supply any significant current? If you have a resistance meter, what resistance do you see between the +12V in terminal of the display and 0V/GND of the display when it is disconnected from the circuit which powers it? Try running something else, maybe just a resistor with the right value, on the 12V supply - presumably 12VDC? - which normally feeds the display. (disconnect the display). See if it holds up at 12V when it is supplying a load.