| 摘要 |
A driver circuit provides a driving signal to the power stage of a switched mode power supply in correspondence with a pulse width modulated duty cycle. A voltage doubler circuit including a bucket capacitor and plural switches is arranged to successively couple the bucket capacitor to the input power source and to the driver circuit. The voltage doubler circuit thereby provides the driving signal to the driver circuit having a voltage approximately double the corresponding voltage of the input power source. The voltage doubler circuit discharges the bucket capacitor into the driver circuit to provide the driving signal in correspondence with a first portion of the pulse width modulated duty cycle, and the voltage doubler circuit recharges the bucket capacitor in correspondence with a second portion of the pulse width modulated duty cycle. The power switch comprises an internal capacitance, wherein charge stored in the bucket capacitor is transferred to the internal capacitance of the at least one power switch during the first portion of the pulse width modulated duty cycle. Remaining charge in the internal capacitance of the power switch is recycled back to the bucket capacitor during the second portion of the pulse width modulated duty cycle.
|
