The .000001% of use cases for a simple passive VGA to HDMI is for when the video source is designed especially to output both VGA and HDMI. In these cases the cable will accompany the video source when you buy it. This is so rare, I almost regret writing this much about it. Analog vs Digital.
Definition - What does Pulse Width Modulation (PWM) mean? Pulse-width modulation (PWM) is a modulation process or technique used in most communication systems for encoding the amplitude of a signal right into a pulse width or duration of another signal, usually a carrier signal, for transmission.
That's the basics of what a PWM is. Its a device a device that breaks up a DC voltage (like the 12 volts from our car's electrical system) into pulses which can be changed to our needs. When we change the width of the pulses, we are modulating them. Hence it should now be clear what Pulse Width Modulator means.