| 摘要 |
PURPOSE:To prevent the internal noise of a circuit from affecting an input level by isolating the circuit set between an input terminal and the first stage and boosting up the level of the circuit with use of the capacity. CONSTITUTION:A 1st transistor TRQ5 has its source connected to an input terminal VIN, and a 2nd TRQ6 has its gate connected to a ground potential GND and its drain connected to the input sides of the 1st inverters Q7 and Q8 respectively. Then the feedback circuits Q11-Q14 have their output terminals connected to the input sides of the inverters Q7 and Q8. A contact 6 is set in a floating state when the TRQ6 has its GND level floated by the noise. At the same time, the TRQ7 is changed to ON from OFF when the TRQ8 has its floating GND level. Then a contact 7 is changed to a high level from a low level. In such a case, however, the TRQ12 and Q13 are turned on and a contact 13 is set at a high level. Thus the contact 6 is boosted up and corrected to a high level with use of the capacity C1. |
