| 摘要 |
PROBLEM TO BE SOLVED: To prevent a device which controls an output voltage from malfunctioning by using a switch by generating the control signal of the switch according to comparison between a triangular wave and a slice level signal and superposing this control signal on the slice level signal. SOLUTION: When a driving circuit 21 drives a switching element 23 by using a pulse signal 5, delay of the driving circuit 21 and operation delay of the switching element 23 itself are generated, so the timing wherein the switching element 23 turns on or off is about several μs delayed behind the timing wherein the pulse signal 4 as the output of a logic circuit 14 rises or fall. Here, the pulse signal 4 is superposed on the slice level signal 2 to increase the margins of the triangular wave 1 and slice level signal 2 when the switching element 23 turns on or off. Consequently, the possibility that a comparator 12 malfunctions is reduced. |
