Typical VFDs show several digits or letters—and maybe preformed words too (like Manual, Auto, AM, PM, Defrost, or whatever). Apart from the display itself, VFDs also need a way of being "driven" (controlled electronically from whatever circuit they're attached to)—and there are two ways of doing this. One is to use separate pin connections to each segment of the display and a single grid. This method is called static drive. Another method uses lots of different grids (one for each segment) that are turned on and off in rapid succession (typically over 100 times a second) by a microprocessor (single-chip computer). Each segment of the display that appears to be permanently turned on is actually flashing on and off very quickly (too quick for our eyes to notice) in sequence. This approach is called multiplexing (or dynamic drive) and has the advantage of needing simpler drive circuitry (fewer chips and pin connections) than static drive.
