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I'm putting together a circuit board to power and dim 5 LED channels.

The average voltages on the channels are 12.3V, 11V, 11.4V, 7.8V, 6.6V, and max current is 1A.

So my current plan is:

12V Constant Voltage Power Supply input... splits into three LM2940CT-12 LDOs, and two 7808 linear regulators.

So I should have more or less 3 x 12V and 2 x 8V signals. Then I'll use a microcontroller with 5 x 5V PWM outputs to switch five line-level N-MOSFETs (eg. IRL520N), to dim the 12V and 8V signals before they reach the 5 LED channels.

I'm a noob at electronics, so there might be a better way. Looking for confirmation or suggestions on how to improve this design.

Thanks

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LEDs are generally driven by current, not by voltage. Otherwise you will not have constant brightness as the led's current consumption will change significantly with rising temperature and an unstable supply voltage. You should google for an led driver IC (meaning constant current source) that fits your needs. They often have a control pin which can be directly supplied with a mc's pwm signal at logic level or even an analog signal for "real" dimming. The datasheet will give you a "typical application" which you simply have to adapt. It's not more to do than in your way, bit at least it's the clean way to drive an led!

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