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Topic: Smaller Darlington array replacement (Read 801 times) previous topic - next topic


I'm looking to control some LEDs that could be between 1W and 3W.
I've been using the ULN2803A but it's kind of big, I only need 3 channels.
ULN2001 is slightly smaller but not by much.
What would be a good replacement?


3 transistors with a base current limiting resistor for each.
At 5V, 3W = 600mA current flow.
N-Channel Logic Level MOSFET with low Rds would be best choice.
with 10K resistor from Gate to Gnd to keep it turned off while Arduino resets, and 180 ohm resistor from Arduino to Gate to limit Arduino drive current to ~25mA.

3W, you would have smoked the ULN2803 eventually.
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What about with a 1W LED?
Would a ULN2803A be able to handle that?

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