Hysteretic switching regulator and control method used therein

A non-isolated hysteretic switching regulator that converts an input voltage supplied to an input terminal into an output voltage output to an output terminal, the switching regulator comprising:

• a switching transistor to alternately switch on and off current flow therethrough,
• an inductor to charge at the input voltage when the switching transistor is on, and discharge when the switching transistor is off;
• a feedback voltage generator to generate a first feedback voltage at a first feedback node by dividing the output voltage;
• a hysteresis comparator circuit having a voltage comparator to compare the first feedback voltage against a reference voltage to output a comparator output signal as a result of the comparison;
• and
• a feedback loop circuit to feed the comparator output signal back to the feedback voltage generator to generate a second feedback voltage at a second feedback node,
• the first feedback voltage having an alternating current component substantially dependent on the second feedback voltage varying with the comparator output signal.

A control method for use in a non-isolated hysteretic switching regulator that converts an input voltage supplied to an input terminal into a variable output voltage output to an output terminal,

• the switching regulator including:
• a switching transistor to alternately switch on and off current flow therethrough according to a switching control signal applied to a control terminal thereof,
• an inductor to charge at the input voltage when the switching transistor is on, and discharge when the switching transistor is off;
• and
• a rectifier to pass current flow therethrough when the inductor discharges,
• the method comprising:
• generating a first feedback voltage by dividing the output voltage through multiple resistors connected in series;
• comparing the first feedback voltage against a reference voltage to output a result of the comparison;
• generating the switching control signal based on the comparison result;
• and
• feeding the comparison result back to the feedback voltage generation to generate a second feedback voltage,
• the first feedback voltage having an alternating current component substantially dependent on the second feedback voltage varying with the comparison result.