摘要 |
A driver circuit charges a capacitive load to a voltage substantially equal to the voltage or potential of the power supply of the circuit by first charging the capacitive load with current flowing through a drive transistor under the control of the power supply potential and, thereafter, at a predetermined time charging the capacitive load under the control of a precharged bootstrap capacitor. The driver circuit includes a transistor, acting as a pull-up device, connected between the power supply and the capacitive load and a series circuit including a charge source and switching means connected between the capacitive load and a control gate of the transistor. The switching means is coupled to the capacitive load so as to be responsive to the voltage at the load for directing charge from the charge source into the pull-up transistor at a predetermined time to raise the voltage at the capacitive load to substantially the potential of the power supply. |