| 摘要 |
PURPOSE:To prevent a through current from being generated in a second bipolar transistor, etc., by providing a MOS transistor which quickly discharges the electric charge of the base parasitic capacitor of a second bipolar transistor at the time of transiting the level of an input signal. CONSTITUTION:An N-channel MOS transistor M1 whose gate is connected to the collector of a first bipolar transistor Q1, and whose source to a ground terminal, and whose drain to the emitter of the first bipolar transistor Q1 and is turned on when the first bipolar transistor Q1 is turned off is provided. And the value of a resistor R1 is increased as far as possible in a range possible to perform the on and off driving of a bipolar transistor Q2. Therefore, the electric charge in the base input capacitor, etc., of the bipolar transistor Q2 when the input signal IN is set at a high level is quickly discharged by the MOS transistor M1 and the resistor R1, which quickly sets the off-state of the bipolar transistor Q2. Thereby, when a bipolar transistor Q3 is turned on, the bipolar transistor Q2 is turned off, which prevents the through current from being generated. |
