| 摘要 |
<P>PROBLEM TO BE SOLVED: To obtain an inexpensive gate drive circuit which can drive the gate of a switching element even with a pulse signal having an on-duty of 50% or more. <P>SOLUTION: The gate drive circuit comprises transistors Q2, Q3 connected in totem pole to both ends of a DC power supply Vcc1 and having a base receiving a pulse signal, respectively, transistors Q4, Q5 connected in totem pole to both ends of a DC power supply Vcc2 and having an emitter being connected to the gate of a switching element Q1, respectively, and a transformer T1 having a primary winding P1 connected to the emitters of the transistors Q2, Q3 and the collector of one of the transistors Q2, Q3 via a capacitor C1, and a secondary winding S1 connected to the bases of the transistors Q4, Q5 and the emitters of the transistors Q4, Q5. The maximum on-duty of a pulse signal Vin is determined based on the primary winding voltage Vp of the transformer T1 and the base-emitter forward voltage of the transistors Q4, Q5. <P>COPYRIGHT: (C)2013,JPO&INPIT |
