> I can't see why light fixtures in buildings—except modern ones where the lights are actually dimmable—would even have any sort of PWM.
It is done because, like most crappy things in the world, it saves somebody, somewhere, a few cents on the dollar.
Most people would not be able to tell the CRI impact of DC dimming vs PWM. Many do not visibly notice the difference. (I unfortunately do, and you won’t believe how many expensive Mercedes and similar cars flicker).
But high frequency PWM is slightly more difficult and expensive, and DC dimming might need a few more capacitors or inductors… so let’s save a buck there, shall we?
It is done because, like most crappy things in the world, it saves somebody, somewhere, a few cents on the dollar.
Most people would not be able to tell the CRI impact of DC dimming vs PWM. Many do not visibly notice the difference. (I unfortunately do, and you won’t believe how many expensive Mercedes and similar cars flicker).
But high frequency PWM is slightly more difficult and expensive, and DC dimming might need a few more capacitors or inductors… so let’s save a buck there, shall we?