I want to try out controlling LED strip brightness/colour (via Arduino that can't supply enough power) and I understand this can be done either with using Transistor as a Switch or as an Amplifier.
1) as a Switch, using
PWM (Pulse-width modulation) to switch the transistor on/off many times per second to simulate the desired voltage. This is for some reason the preferred way according to my Googling results. However I am a bit afraid of flickering, some people are more sensitive to it than others, but I want really smooth fading. Is there some mechanism to stabilize the outputs of the switch to be less discrete? That brings me to the other option:
2) as an Amplifier, where small changes in the input voltage result in bigger absolute changes in the output voltage. My naive understanding is that this could be more "smooth" in terms of the voltage supplied to the LED and thus prevent any flickering.
What are the drawbacks of option 2? Why is the option 1 more common? The factors that come to my mind include price, complexity of setup, overheating and possible problems with non-linear characteristics of Amplifiers, but I am rather guessing here.