Auto cascode buck voltage converter
AssigneeCSR Technology Inc.
InventorLudovic Oddoart
Life of this patent
Estimating the term…
Abstract
A voltage converter includes a power switch having respective charging and discharging control terminals, and an output terminal coupled to a series connected inductor and capacitor. The voltage converter also includes a charging switch coupled to the charging control terminal of the power switch, a discharging switch coupled to the discharging control terminal of the power switch, and a feedback circuit coupling the power switch, charging switch and discharging switch to a node at which the capacitor and inductor are connected. During a charging phase, the charging switch couples the capacitor to the charging control terminal of the power switch, and during a discharging phase, the discharging switch couples the capacitor to the discharging control terminal of the power switch.
Claims22
A voltage converter comprising:
- a power switch, coupled between a source of battery potential and a source of reference operating potential, the power switch having respective charging and discharging control terminals configured to receive respective charging and discharging control signals, and an output terminal;
- an inductor connected in series with a capacitor, the series connected inductor and capacitor being coupled between the output terminal of the power switch and the source of reference operating potential;
- a charging switch having an output terminal coupled to the charging control terminal of the power switch;
- a discharging switch having an output terminal coupled to the discharging control terminal of the power switch;
- a pulse width modulation (PWM) controller controlling the charging switch and discharging switch;
- a feedback loop directly connecting a node at which the capacitor and inductor are connected to the power switch, charging switch and discharging switch exclusive of the PWM controller,
- wherein during a charging phase, the charging switch electrically couples the capacitor to the charging control terminal of the power switch, whereby the power switch charges the inductor, and
- wherein during a discharging phase, the discharging switch electrically couples the capacitor to the discharging control terminal of the power switch, whereby the power switch discharges the inductor.
A voltage converting method of operating a voltage converter, the voltage converter comprising a charging switch, a discharging switch, a power switch coupled between a source of battery potential and a source of reference operating potential, a series-connected inductor and capacitor coupled between the power switch and the source of reference operating potential, a pulse width modulation (PWM) controller controlling the charging switch and discharging switch, and a feedback loop coupling the charging switch, the discharging switch and the power switch to a node at which the capacitor is connected to the inductor exclusive of the PWM controller, the voltage converting method comprising:
- applying, exclusive of the PWM controller, via the feedback loop and during a charging phase, a capacitor voltage from the capacitor directly to a charging control terminal of the power switch, causing the power switch to apply a charging potential from the source of battery potential to the inductor;
- and
- applying, exclusive of the PWM controller, via the feedback loop and during a discharging phase, the capacitor voltage from the capacitor directly to a discharging control terminal of the power switch, causing the power switch to apply a discharging potential from the source of reference operating potential to the inductor.
A voltage converter comprising:
- a power switch, coupled between a source of battery potential and a source of reference operating potential, the power switch having respective charging and discharging control terminals configured to receive respective charging and discharging control signals, and an output terminal;
- an inductor connected in series with a capacitor, the series connected inductor and capacitor being coupled between the output terminal of the power switch and the source of reference operating potential;
- a low voltage charging switch having an output terminal coupled to the charging control terminal of the power switch;
- a high voltage charging switch having an output terminal coupled to the charging control terminal of the power switch;
- a discharging switch having an output terminal coupled to the discharging control terminal of the power switch;
- a PWM controller coupled to control terminals of the low voltage and high voltage charging switches, the controller being coupled to the source of battery potential for controlling the low and high voltage charging switches;
- and
- a feedback loop directly connecting the power switch, low voltage charging switch, high voltage charging switch and discharging switch to a node at which the capacitor is connected to the inductor exclusive of the PWM controller,
- wherein, during a low voltage charging phase, when a battery potential provided by the source of battery potential is determined by the PWM controller to be less than or equal to a predetermined threshold, the low voltage charging switch couples the source of reference operating potential to the charging control terminal of the power switch, whereby the power switch charges the inductor,
- wherein, during a high voltage charging phase, when the battery potential is determined by the PWM controller to be greater than the predetermined threshold, the high voltage charging switch couples the capacitor, via the feedback loop, to the charging control terminal of the power switch, whereby the power switch charges the inductor, and
- wherein, during a discharging phase, the discharging switch couples the capacitor, via the feedback loop, to the discharging control terminal of the power switch, whereby the power switch discharges the inductor.
Dependencies are inferred from the claim text.