Control device for a switching voltage regulator having reduced audio noise and control method

A switching voltage regulator, comprising:

• a control device, including:
• a burst-mode controller configured to:
• receive a set of measurement signals including a first measurement signal indicative of an output voltage of the switching voltage regulator,
• monitor the output voltage with respect to a first threshold and a second threshold higher than the first threshold, and
• generate a burst signal in response to the monitoring the output voltage with respect to the first threshold and the second threshold;
• and
• driving-signal generation circuitry configured to:
• generate at least one switching control signal based on the burst signal and the set of measurement signals, the driving-signal generation circuitry including a feedback circuit configured to generate a control signal based on the burst signal and an error signal, the error signal indicative of a difference between the first measurement signal and a reference signal,
• regulate the reference signal between a minimum value and a maximum value in response to the output voltage reaching the first threshold, and
• modify the reference signal from the maximum value to the minimum value in response to the output voltage reaching the second threshold;
• and
• a switching circuit configured to receive the at least one switching control signal, the switching circuit including at least one switch configured to be controlled by the at least one switching control signal and having an input node configured to receive an input voltage and an output node configured to provide the output voltage based on the input voltage.

A control method for a switching voltage regulator including a switching circuit and a control device, the control method comprising:

• receiving a set of measurement signals including a first measurement signal indicative of an output voltage of the switching voltage regulator;
• monitoring the output voltage with respect to a first threshold and a second threshold higher than the first threshold;
• generating a burst signal in response to the monitoring the output voltage with respect to the first threshold and the second threshold;
• generating at least one switching control signal for the switching circuit based on the burst signal and the set of measurement signals, wherein generating the at least one switching control signal comprises generating a control signal based on the burst signal and an error signal, the error signal indicative of a difference between the first measurement signal and a reference signal;
• regulating the reference signal between a minimum value and a maximum value in response to the output voltage reaching the first threshold;
• and
• modifying the reference signal from the maximum value to the minimum value in response to the output voltage reaching the second threshold.