Re: Multiplexing LEDs - calculating resistor value

Hi roxlu,

your intensity problem come from the fact that you used a single resistor for you N leds (not sure if you switch on 8 or 48 at a time). When 1 led is on, you've got x volts drops across the resistor. When you light 2 leds, you've got 2x volts drop, and so on ...

If you switch on one *row* at a time, you'll need one resistor per *column*.

vic
.

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