| 摘要 |
PURPOSE:To simplify a circuit configuration, by providing a transistor for short- circuiting the base and the emitter of both transistors, in a totem pole circuit consisting of a constant-current transistor and an output transistor. CONSTITUTION:On a totem pole circuit consisting of a constant-current transistor TR10 and an output transistor TR1, transistors Q1, Q3 for short-circuiting the base and the emitter of both the transistors TR10, TR1 are provided. In this state, an output terminal OUT connected to the collector of the output transistor TR1 is set to ''0'' level and ''1'' level by applying a driving signal DRV of a low level. Also, the output terminal OUT is made to high impedance and is made to the third level being floating, by cutting the voltage between the base and the emitter of the constant-current transistor TR10 and the output transistor TR1 by the transistors Q1, Q3. |
