Circuit for shortening the turn-off time of a power transistor

摘要

A circuit and method for driving an inductive load has a first transistor (51) with a current flow path connected to provide drive current at an output node to the inductive load, and a control element for controlling the current in the first current flow path. The control element is adapted for connection to receive a control signal for turning the current in the first current flow path of the first transistor on and off. A second transistor (58) has a current flow path connected between the output node and the control element of the first transistor, and has a control element for controlling the current in the current flow path. A capacitor (60) is connected between the control element of the second transistor and a reference potential, the capacitor being much larger than an inherent capacitance at the control element of the first transistor divided by a current gain of the second transistor. Finally, a rectifier (62) is connected between the output node of the first transistor and the capacitor. The transistors can be, for example, of NPN, field effect, n-channel MOS, or other transistor construction that can be easily integrated into an integrated circuit chip.