Pulse control method

A control method using pulses in switching power supplies, where the frequency is kept constant and the output is controlled by varying the on-time in each cycle. The ratio of the on-time Ton to the cycle T is called the duty cycle and is expressed by the following formula.

Duty cycle D = Ton/T

Even if the input voltage or output current fluctuates, the output voltage can be kept constant by varying this duty cycle.