GATE DRIVE CIRCUIT FOR SEMICONDUCTOR SWITCHING ELEMENT

摘要

PURPOSE:To reduce the power consumption at charging/discharging an input capacitance of a semiconductor switching element by giving a DC bias voltage near its threshold voltage in series with a pulse transformer connected between a gate terminal and a source terminal of the semiconductor switching element such as a MOSFET. CONSTITUTION:A constant voltage source 10 is connected in series between a secondary winding terminal (h) of a pulse transformer 2 and a source terminal of a MOSFET 3. A voltage V0 of the constant voltage source 10 is set near the gate-source threshold voltage Vth of the said MOSFET 3 with respect to the input capacitance Ciss of the MOSFET 3. Thus, a voltage change width V2-V3 at turn-on turn-off state is made sufficiently smaller than that of a conventional circuit and the power consumption at charge/discharge of the input capacitance Ciss is reduced.