Control circuit for step-up switching regulator

A control circuit for a step-up switching regulator comprising:

• a switching terminal to which an inductor is connected;
• a switching transistor arranged between the switching terminal and a ground terminal;
• a feedback terminal configured to receive a feedback voltage that corresponds to an output voltage of the step-up switching regulator;
• an error amplifier configured to amplify the difference between the feedback voltage and a predetermined reference voltage so as to generate an error voltage;
• a pulse modulator configured to generate a pulse signal having a duty ratio that is adjusted according to the error voltage;
• a driver configured to drive the switching transistor according to the pulse signal;
• and
• an overvoltage detection circuit configured to compare the voltage at the switching terminal with a predetermined threshold voltage, and to generate an overvoltage protection signal which is asserted when the voltage at the switching terminal becomes higher than the threshold voltage while the switching transistor is off, wherein, when the overvoltage protection signal is asserted, the control circuit is configured to perform a predetermined protection operation, and wherein the overvoltage detection circuit comprises a switch arranged between two resistors and configured to perform a switching operation in a manner complementary to the switching operation of the switching transistor.