I'm building a driver for a large common-cathode 7-segment display using a shift register and BJT transistors (more details in this question).
I wanted to make it more compact by replacing the transistors for a Darlington array such as ULN2003 or ULN2803, but these only sink current and I can only figure out how to use them to drive common-anode displays.
Is there a way I can use these Darlington arrays to drive common-cathode displays?
If not, are there Darlington arrays, such ULN2003 or ULN2803, that source current? If not, why not? Is it because the IC would require more transistors (as explained to me in here) and thus it would be more expensive to produce?
Should I just prefer to drive common-anode displays instead? For some reason I think there should be some simmetry in this, but apparently there's not.
Best Answer
Sourcing drivers are not as common as sinking drivers. I often use the UDN2981 / TD62783 as a 'high-side ULN2803'.