As the world of lighting moves more and more into LED sources, Pulse Width Modulation (PWM) has become the most common means for controlling LEDs. What is PWM exactly and, more importantly, how does it relate to lighting applicationis it and how does it affect your lighting design?
Pulse Width Modulation — Defined
“Pulse Width Modulation” refers to a technique where a microcontroller rapidly turns the power to a device (in our example an LED chip) on and off at a given frequency and with a certain “pulse width.” By controlling the frequency (how fast the on/off pulse cycle occurs) we can control whether or not the human eye, high-speed cameras, or other image capture devices can visibly detect the occurrence of the pulses. This is extremely important because, if the pulses are produced slow enough to be perceived, “flickering” is visible.
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