| 摘要 |
PURPOSE:To apply a reversed bias charge without increasing the total ON resistance by providing an ON signal output means which never transmits an ON signal to a 1st switching means as long as a 2nd switching means is kept ON. CONSTITUTION:A diode 5 functions to prevent a DC power supply 2 and a resistor 9 from supplying the reversed base bias voltage to a transistor TR (1st switching means) 4 when a switch (2nd switching means) 3 is kept OFF. Then a forward base bias current is acquired when a current flows to a resistor (ON signal output means) 8. Under such conditions, the TR 4 in turned on. Meanwhile the supply 2 and the resistor 9 always supply the reversed base bias voltage to the TR 4 via the switch 3 and a diode 6 when the switch 3 is kept ON. Thus the TR 4 is completely turned off. Thus the total ON voltage (resistance) is reduced for a switching circuit owing to a fact that only the diode 5 and the switch 3 exist between both terminals t2 and t3. |
