Patent ID: 6094087
Filing Date: 2000-07-25
Classification: H02M,H03K,Y02B

Abstract:
A gate drive circuit for an isolated gate device, comprising:a capacitor, having a first terminal coupled to a source of drive voltage and a second terminal coupled to a gate of said isolated gate device, that stores a charge therein when said drive voltage maintains said isolated gate device in an ""on"" state;a conductive path, leading from said first terminal to a terminal of said isolated gate device and enabled when said isolated gate device is to be transitioned from said ""on"" state to an ""off"" state, that provides a path for a negative off-bias voltage from said capacitor to discharge a gate capacitance of said gate thereby to avoid spurious turn-on of said isolated gate device;a zener diode, coupled between said second terminal and said terminal of said isolated gate device, that limits a positive value of said drive voltage thereby regulating said negative off-bias voltage; anda blocking diode, serially-coupled in opposition to said zener diode, that prevents said zener diode from conducting when said isolated device is in said ""off"" state.