250V 1A Three-Phase Monolithic Inverter IC for Brushless Motor Drives

Abstract

This paper describes a high voltage three-phase monolithic inverter IC using dielectrically isolated power IC technology. This inverter IC has the ability to drive a 50 W brushless motor, and it can be supplied voltage from a commercial voltage source using only a rectifier. This inverter IC includes six insulated gate bipolar transistors (IGBTs) and fast recovery diodes for output stages having a current capability of 1 A for continuous current. The IGBTs and fast recovery diodes realize a reduction in forward voltage drops and fast switching speeds. The IC also provides functions such as drive circuits suitable for pulse width modulation (PWM) control at a switching frequency of 20 kHz, a charge pump type power supply for each upper driver, and unique overcurrent protection circuits on one chip. The drive circuits which prevent the IGBTs from incorrect turning on under the large dV/dt condition, and the overcurrent circuits, provide easy use and enhanced reliability.