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by PedroDiogo_ 5478 days ago
Something like PWM?

I bet Macs don't generate analog voltages to fade the LED, it would be expensive.
2 comments
wizard_2 5478 days ago
LEDs also don't change brightness with voltage, they do with amperage and usually have an optimal amperage for the LED's design. Brightness can be controlled many ways, the most common way is to use Pulse Width Modulation. It's also a common power saving technique.

http://www.reuk.co.uk/LED-Dimmer-Circuit.htm

link
djahng 5477 days ago
The patent they reference in the article states that the LED's current is PWMed, where the modulation function is sinusoidal.
link