Dead time (PWM)
The brief moment when both transistors in a half-bridge are off, inserted deliberately so they never conduct at the same time.
A half-bridge has one transistor to the supply and one to ground, and the PWM signal flips between them. On paper one turns off as the other turns on. In practice a MOSFET switches off more slowly than it switches on, and for a few nanoseconds both conduct. The result is a short circuit straight through the bridge — shoot-through — which at best means heat and at worst a small puff of smoke.
That's why motor-control timers in microcontrollers have complementary outputs with a built-in dead-time generator; on the STM32 it's a field in the advanced timers' registers. Typical values run from a few hundred nanoseconds to a microsecond or so. Too short gives shoot-through; too long gives distortion and needless conduction through the transistors' body diodes. The number is a compromise settled with an oscilloscope, not a datasheet.