Half-bridge power converter system and method of operation
AssigneeFairchild Korea Semiconductor Ltd.
InventorsHang-Seok Choi, Han-Suk Seo
Life of this patent
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Abstract
In one embodiment, a power converter generates an output voltage by modulating an input voltage according to operations of a first switch and a second switch connected in a half-bridge arrangement. The power converter includes a switch driver circuit for controlling the turning on and off of the first and second switches. A PWM controller generates a switch driver control signal for controlling the switch driver circuit according to an output voltage. The switch driver circuit generates an on-time control signal for turning off the first switch when the first switch has been turned on for longer than a threshold period.
Claims15
A power converter system, comprising:
- a high-side switch and a low-side switch connected in a half-bridge arrangement;
- a switch driver circuit for controlling the turn-on and turn-off of the high-side switch and the low-side switch in the half-bridge arrangement;
- and
- a pulse width modulation (PWM) controller for generating a switch driver control signal for controlling the switch driver circuit according to an output voltage, wherein the output voltage is generated by modulating an input voltage according to operations of the high-side switch and the low-side switch;
- and
- the switch driver circuit detects the switch driver control signal, generates an on-time control signal when the switch driver control signal turns on the high-side switch for longer than a threshold period, the on-time control signal for turning off the high-side switch, the switch driver circuit comprising:
- a first dead-time controller for controlling a dead time of the high-side switch;
- a second dead-time controller for controlling a dead time of the low-side switch;
- an on-time controller for determining whether the high-side switch turns on during the threshold period, and generating the on-time control signal;
- and
- a logic operation unit for performing a logic operation on a first dead-time control signal output from the first dead-time controller and the on-time control signal, the logic operation unit generating the on-time control signal for turning off the high-side switch.
A switch driving apparatus for controlling the turning on and off of a high-side switch and a low-side switch in a half-bridge power converter, the switch driving apparatus comprising:
- an input terminal for receiving an input control signal;
- a first dead-time controller for providing a first control signal to keep the high-side switch turned off for a first dead-time period after the input control signal transitions from a first level to a second level;
- a second dead-time controller for providing a second control signal to keep the low-side switch turned off for a second dead-time period after the input control signal transitions from the second level to the first level;
- and
- an on-time controller for providing an on-time control signal for turning off the high-side switch if the high-side switch has been turned on for longer than a threshold period.
A method for driving a power converter system that modulates an input voltage by using operations of a high-side switch and a low-side switch connected in a half-bridge arrangement, the method comprising:
- generating a first switch control signal and a second switch control signal for respectively controlling the high-side switch and the low-side switch;
- generating an on-time control signal when the first switch control signal is maintained at a first level for longer than a first period;
- and
- performing a logic operation on the on-time control signal and the first switch control signal and generating a high-side switch off signal for turning off the high-side switch according to a result of the logic operation.
Dependencies are inferred from the claim text.