A controller includes a first circuit that receives first and second input signals and generates an output pulse based on the first and second input signals. A timer circuit of the controller generates the first input signal for the first circuit. A second circuit of the controller generates the second input signal for the first circuit. In response to the second input signal being set to a first value, smaller than a second value, the first circuit sets the output pulse to the second value and start a first duration. In response to the second input signal being set to the second value and the first input signal changing from the first value to the second value, the first circuit sets the output pulse to the first value to end the first duration and start a second duration such that the second duration is maintained more than a time limit.