Buck-boost power converter and method of operation thereof
AssigneeFuturewei Technologies, Inc.
InventorsHeping Dai, Liming Ye, Jinbo Huang, Dianbo Fu
Life of this patent
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Abstract
A method comprises detecting an input voltage and an output voltage of a buck-boost converter, wherein the buck-boost converter comprises a first high-side switch and a first low-side switch connected in series across an input capacitor, a second high-side switch and a second low-side switch connected in series across an output capacitor and an inductor coupled between a common node of the first high-side switch and the first low-side switch, and a common node of the second high-side switch and the second low-side switch and configuring the buck-boost converter such that at least one of the first high-side switch and second low-side switch operates at a fixed duty cycle mode.
Claims18
A method comprising:
- detecting an input voltage and an output voltage of a buck-boost converter, wherein the buck-boost converter comprises:
- a first high-side switch and a first low-side switch connected in series across an input capacitor;
- a second high-side switch and a second low-side switch connected in series across an output capacitor;
- and
- an inductor coupled between a common node of the first high-side switch and the first low-side switch, and a common node of the second high-side switch and the second low-side switch;
- and
- configuring the buck-boost converter such that:
- configuring the buck-boost converter to operate in a buck PWM mode when the input voltage is greater than a first predetermined threshold, in a boost PWM mode when the input voltage is less than a second predetermined threshold, and in a buck-boost PWM mode when the input voltage is between the second predetermined threshold and the first predetermined threshold, wherein the first predetermined threshold is greater than the second predetermined threshold, and the output voltage is between the first predetermined threshold and the second predetermined threshold;
- during the entire buck PWM mode, configuring the second low-side switch to operate at a fixed duty cycle mode and the first high-side switch to operate at the buck PWM mode, wherein during the fixed duty cycle mode, the second low-side switch performs an on/off operation at least once in each switching period;
- and
- during the boost PWM mode, configuring the second low-side switch to operate at the boost PWM mode and the first high-side switch to operate at a constant-on mode.
A method comprising:
- providing a power converter, wherein the power converter comprises:
- a buck converter portion comprising a first high-side switch and a first low-side switch connected in series across an input capacitor;
- a boost converter portion comprising a second high-side switch and a second low-side switch connected in series across an output capacitor;
- and
- an inductor coupled between a common node of the first high-side switch and the first low-side switch, and a common node of the second high-side switch and the second low-side switch;
- detecting an input voltage and an output voltage of the power converter;
- and
- configuring the power converter such that the power converter operates in either a buck converter mode or a boost converter mode depending on different input and output voltages, and wherein in an entire buck converter mode or an entire boost converter mode, one portion of the power converter operates at a fixed duty cycle mode and the other portion of the power converter operates at a PWM mode, wherein:
- the one portion of the power converter leaves the fixed duty cycle mode and enters the PWM mode when the input voltage is close to the output voltage and during the fixed duty cycle mode, the one portion of the power converter performs an on/off operation at least once in each switching period.
Dependencies are inferred from the claim text.