| 摘要 |
PURPOSE:To prevent erroneous action due to simultaneous action by providing a level sensing circuit and a threshold changing circuit to the input buffer of an integrated circuit. CONSTITUTION:Inverters 2 and 3 of an input buffer 1 are respectively composed of P channel transistors 5 and 7, and N channel transistors 6 and 8, and an LT inverter 4 is composed of a P channel transistor 9 and an N channel transistor 10. When an input signal is a high level, a GND level is raised by the simultaneous action of an output and the rise of the GND level is sensed by the LT inverter 4, an N channel transistor 12 is turned on, and the threshold level of the input circuit is lowered. Thus, the erroneous action due to the synchronizing action of the output can be prevented. |
