DC-DC converter, electronic equipment and method for realizing soft start of DC-DC converter

The application relates to a DC-DC converter, electronic equipment and a method for realizing soft start of a DC-DC converter; the duty ratio of the pulse width modulation signal is adjusted by using a sampling voltage, so that the conduction duration of a PMOS power tube and an NMOS power tube is adjusted, and the inductive current is switched between reduction and increase. Moreover, by setting the proper preset voltage and preset duration, the inductive current can be increased from a lower initial point, and the increase duration of the inductive current in a period is limited, so that the damage to an external load caused by outputting a larger inductive current to the external load is prevented. 本申请的DCDC转换器、电子设备及DCDC转换器的软启动方法使用采样电压来调整脉宽调制信号的占空比，从而调节所述PMOS功率管和NMOS功率管的导通时长，使所述电感电流在减小和增大之间切换。并且，通过设置合适的预设电压和预设时长，可以让所述电感电流从一个较低的初始点开始增大，并且限制所述电感电流在一个周期内的增大时长，防止输出较大的电感电流至外接负载，造成外接负载的毁损。