Control circuit and control method for switching regulator

A control circuit for a switching regulator having a switching transistor, comprising:

• a first comparator configured to compare a feedback voltage that corresponds to the output voltage of the switching regulator with a predetermined lower threshold voltage, and to output a voltage comparison signal which is asserted when the feedback voltage drops to the lower threshold voltage;
• a second comparator configured to compare an electric current that flows through the switching transistor with a predetermined reference current, and to generate a current comparison signal which is asserted when the current reaches the reference current;
• a logic unit configured to receive the voltage comparison signal and the current comparison signal, and to generate a control signal which is set to a first-level state during a period in which the switching transistor is to be turned on, and which is set to a second-level state during a period in which the switching transistor is to be turned off;
• and
• a driver configured to drive the switching transistor according to the control signal,
• wherein, during a period in which the voltage comparison signal is asserted, the logic unit repeatedly performs an operation in which, when the current comparison signal is asserted, the control signal is set to the second level, following which, after the passage of a predetermined period of OFF time, the control signal is set to the first level.