| 摘要 |
PURPOSE:To prevent the malfunction of a semiconductor device, by using an npn-bipolar transistor as the transistor to be connected with the high-potential power source side of the output section and providing an n-channel MOS transistor, whose drain is connected with the input terminal and source and gate area connected to a lowpotential power source. CONSTITUTION:Since an npn-bipolar transistor Q5 is connected with the high- potential power source side of an output section, no parasitic diode is formed between the collector and emitter of the transistor Q5. Therefore, such a trouble that a semiconductor device with a three-state output wrongly operates when the power supply is turned off never takes place. Moreover, since an-channel MOS transistor Q8 is connected with an input section and the substrate area, in which the MOS transistor Q8 is formed, is connected with a GND terminal 3, a parasitic diode 21 is formed between the drain of the transistor Q8 and GND terminal 3 and a high static destruction resisting pressure is given to the input section by the action of the MOS transistor Q8. Therefore, the malfunction is prevented. |
