Patent Number: 6,297,690

Title: Booster circuit

Abstract: A booster circuit uses a source voltage to generate a boosted voltage thatis higher than the source voltage. The booster circuit has two capacitors.The two capacitors are alternately charged and discharged in response to asignal voltage applied to an input terminal. The first capacitor isdischarged to boost the voltage at a boosting node, whereas the secondcapacitor is discharged to boost the voltage at an output terminal.Further, the booster circuit includes a control circuit. When the voltageat the input terminal changes from an "H" level to an "L" level, thecontrol circuit supplies a voltage for discharging the first capacitor tothe first capacitor after the second capacitor has been brought into acharging state. Since the voltage at the output terminal is reduced by thecharging of the second capacitor, a transistor is deactivated in responseto the voltage at the output terminal. As a result, the boosting node andthe source voltage can be prevented from being coupled by the transistor.The voltage at the boosting node is boosted by the discharge of the firstcapacitor, and the output terminal and the source voltage are coupled by atransistor that is activated in response to the boosted voltage at theboosting node. It is thus possible to increase the voltage at the outputterminal to the source voltage V.sub.CC.

Inventors: Matsushita; Yuichi (Miyazaki, JP)


International Classification:

Expiration Date: 10/02/2013