Monostable trigger driving circuit made of 555 time base circuit

As shown in Figure 4, the 555 time base circuit (IC) is connected in the form of a monostable trigger, and the motor M is connected between the IC output terminal pin 3 and the ground, and the pin 2 is the trigger signal input terminal. Normally, the output signal V=0 at pin 3, and the motor does not rotate. When a negative trigger pulse Vi acts on pin 2, the monostable trigger flips to a temporary stable state, and the output signal Vo=VCC at pin 3, and the motor M rotates. After a certain period of time, the monostable trigger returns to a stable state, Vo=0, and the motor M stops. The characteristic of the monostable trigger driving circuit is that each time the 555 time base circuit is triggered, it drives the load to work for a fixed time, and the working time is equal to the output pulse width D (T=1.1RC) of the monostable trigger.