Patent ID: 8154898
Filing Date: 2012-04-10
Classification: H02M,H05B

Abstract:
1. A circuit for generating a high voltage alternating current to drive a load comprising: a charge pump having a first terminal and a second terminal; an output terminal; a circuit ground terminal; a pair of output capacitive elements attached to the charge pump and the circuit ground terminal to reduce frequency fluctuations, wherein a first output capacitive element is attached to the first terminal of the charge pump and to the circuit ground terminal and a second output capacitive element is attached to the second terminal of the charge pump and to the circuit ground terminal; a first switch wherein a first switch first terminal is connected to the first terminal of the charge pump and the first output capacitive element, a first switch second terminal is attached to the circuit ground terminal, the first switch conducting between the first terminal of the charge pump and the circuit ground terminal when the first switch is closed; a second switch wherein a second switch first terminal is connected to the first terminal of the charge pump and the first output capacitive element, a second switch second terminal is attached to the load terminal, the second switch conducting between the first terminal of the charge pump and the output terminal when the second switch is closed; a third switch wherein a third switch first terminal is connected to the circuit ground terminal and a third switch second terminal is attached to the second terminal of the charge pump and the second output capacitive element, the third switch conducting between the second terminal of the charge pump and the circuit ground terminal when the third switch is closed; a fourth switch wherein a fourth switch first terminal is connected to the load terminal and a fourth switch second terminal is attached to the second terminal of the charge pump and the second output capacitive element, the fourth switch conducting between the second terminal of the charge pump and the output terminal when the fourth switch is closed; and a load coupled to the output terminal and the circuit ground terminal; wherein both the first terminal and the second terminal of the charge pump float to interchange which of the first terminal and the second terminal of the charge pump is grounded to the load; wherein the charge pump is a capacitive charge pump providing an approximately constant current output across variable load voltages; wherein a minimum terminal count of the circuit is 3.