Hi I have 12 common anode RGB leds where each respective cathode and its current limiting resistor (red, green and blue) is tied to the output of 3 arduino pwm signals - red, green and blue. From here I would like to create an enable function to light any one or all at the same time using transistors. These transistors would have to go in between the positive terminal and the load.
1) Should I use npn or pnp? Since I'm switching the positive terminal and not the load(s) it would be pnp?
2) Will there be voltage issues on the pwm signal if there are many sources trying to sink their current at the same time, up to 12? The arduino pin can sink 40ma and I will design for 20ma.
3) Anything else I failed to consider?
Regards,
1) Should I use npn or pnp? Since I'm switching the positive terminal and not the load(s) it would be pnp?
2) Will there be voltage issues on the pwm signal if there are many sources trying to sink their current at the same time, up to 12? The arduino pin can sink 40ma and I will design for 20ma.
3) Anything else I failed to consider?
Regards,
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