US 2013/0293204 A1 · CONTROL CIRCUIT FOR REDUCING SWITCHING LOSS OF BUCK-BOOST CONVERTER AND RELATED SWITCHING REGULATOR

Abstract

The switching regulator of a buck-boost converter includes a first, a second, a third, and a fourth switches. A control circuit for controlling the switching regulator includes an error detector, a ramp signal generator, a comparator, an oscillator, and a control signal generator. The error detector generates an error signal corresponding to an output voltage of the switching regulator. The ramp signal generator generates a ramp signal. The comparator compares the error signal and the ramp signal to generate a comparison signal. The oscillator generates an oscillating signal. The control signal generator controls the first, the second, the third, and the fourth switches according to the comparison signal, the oscillating signal, and a clock signal, so that the switching regulator is configured to switch only between a boost mode and a buck mode, and not to operate at a buck-boost mode.

Claims18

Dependent claims

A control circuit for controlling a switching regulator of a buck-boost converter, wherein the switching regulator comprises a first switch, a second switch, a third switch, and a fourth switch, the control circuit comprising:

an error detector, configured to operably generate an error signal corresponding to an output voltage of the switching regulator;
a ramp signal generator, configured to operably generate a ramp signal;
a comparator, coupled with the error detector and the ramp signal generator, configured to operably compare the error signal and the ramp signal to generate a comparison signal;
an oscillator, configured to operably generate an oscillating signal;
and
a control signal generator, coupled with the comparator and the oscillator, configured to operably control operations of the first, the second, the third, and the fourth switches according to the comparison signal, the oscillating signal, and a clock signal, so that the switching regulator is configured to switch only between a boost mode and a buck mode, and not to operate at a buck-boost mode.

3 more elements

A switching regulator for a buck-boost converter, comprising:

a first switch, comprising a first terminal for coupling with an input voltage and a second terminal for coupling with an external inductor;
a second switch, comprising a first terminal coupled with the second terminal of the first switch;
a third switch, comprising a first terminal for coupling with the external inductor;
a fourth switch, comprising a first terminal coupled with the first terminal of the third switch and a second terminal configured to operably provide an output voltage;
an error detector, configured to operably generate an error signal corresponding to the output voltage;
a ramp signal generator, configured to operably generate a ramp signal;
a comparator, coupled with the error detector and the ramp signal generator, configured to operably compare the error signal and the ramp signal to generate a comparison signal;
an oscillator, configured to operably generate an oscillating signal;
and
a control signal generator, coupled with the comparator and the oscillator, configured to operably control operations of the first, the second, the third, and the fourth switches according to the comparison signal, the oscillating signal, and a clock signal, so that the switching regulator is configured to switch only between a boost mode and a buck mode, and not to operate at a buck-boost mode.

7 more elements

Dependencies are inferred from the claim text.

Control circuit for reducing switching loss of buck-boost converter and related switching regulator

Life of this patent

Control circuit for reducing switching loss of buck-boost converter and related switching regulator

Life of this patent

Abstract

Claims18