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An OP asked where he could get a ULN model, so I drew up a quick hierarchical model using 2N2222A.
If they want a more accurate model its possible to use a LTS transistor model and edit its parameters to suit.
Your example circuit wastes a lot of battery power since the ULN2003 turns the LEDs off by putting all the 12V current in the 330 ohm resistor instead of turning the LEDs on through a less wasteful series resistor then turning the LEDs off without wasting any current.
Ahh, I know.
That's just one example ^^
I designed this circuit because I still have "common cathode" 7 segment LED displays lying around
I will use a ICL7667. The output there can pull to Vdd and GND. The ULN2803 can only pull to GND. The ULN2803 will not work without a pullup resistor.
....excuse me for my terrible english!
Why are you using an ICL7667 Mosfet driver to blow itself up and blow up the LEDs? Your circuit has nothing to limit the current. Its output goes both high or goes low so R1 is not needed.
I do not have a model of an ICL7667 so could you please copy your simulation schematic as a PNG file and post it?