Kohei Onda

A novel high voltage three-phase monolithic inverter IC with two current levels sensing

A 250-V 1-A three-phase monolithic inverter IC (ECN3010) for variable-speed motor drives has been fabricated. Six insulated-gate bipolar transistors (IGBTs) and fast recovery diodes are integrated on one chip, for the output stages, using dielectric isolation. The IC provides many functions for driving a DC brushless motor by itself. A two-current-level sensing circuit has been developed to limit the motor start-up current and to turn off all the IGBTs when a short-circuit load occurs. The accuracy of the sensing circuit and its temperature dependence are discussed.<<ETX>>

New concept high-voltage IGBT gate driver with self-adjusting active gate control function for SiC-SBD hybrid module

We present a new concept in insulated-gate bipolar transistor (IGBT) gate drivers with a blocking voltage up to 3.3kV that have a pulse transformer interface and a function for self-adjusting active gate control. The error-correcting decoder we proposed contributed to the reliability of signal transmission. Moreover, the method of gate control using differentiation of gate voltage could automatically adjust the timing of gate controls against variations in the threshold voltage or collector current without the use of external sensors. These functions were integrated into custom ICs. The new concept high-voltage IGBT gate drivers applied to a 3.3 kV/1200A silicon carbide Schottky barrier diode (SiC-SBD) hybrid-module suppressed ringing in the SiC-SBD and reduced the slew rate by 70%.