Driving large LED array

I have a radar unit that has an single red/green led output and want to amplify this to operate a larger display. The system is 12Vdc and the new led array load is 91mA. What is the best way to do this? Thanks.

by Nzdude
April 06, 2017

1 Answer

Answer by mikerogerswsm

I assume that the radar unit output is 0V for green and +12V for red. If the larger display is the same polarity then all you need to do is use a double emitter follower: PNP transistor with collector to 0V, base to input, emitter to output and NPN transistor with collector to +12V, base to input and emitter to output. Almost any transistor will do, it is low voltage, low current and low power. If the larger display has four wires then take one pair from NPN emitter (+) to 0V (-), and the other pair from PNP emitter (-) to +12V (+). It would be good practice to add a 1A fuse in the +12V supply. Enjoy!

+2 votes
by mikerogerswsm
April 08, 2017

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