Input circuit and semiconductor integrated circuit device including same

摘要

The disclosed input circuit incorporated in semiconductor integrated circuit device will not be operated erroneously due to fluctuations of a supply (or reference) potential caused by noise, for instance. The input circuit includes a signal input terminal for applying an external input signal; a first input potential detecting circuit for comparing a potential of the input signal with a predetermined supply (or reference) potential to detect a potential difference between the two; a second input potential detecting circuit activated in response to a control signal, for comparing the potential of the input signal with the predetermined supply (or reference) potential to detect the potential difference between the two; a delay circuit for delaying an output of the first input potential detecting circuit by a predetermined delay time; a latch circuit for inputting an output signal of the delay circuit as data and an output signal of the second input potential detecting circuit as a clock, to generate an output signal according to potentials of these two inputted signals; and a signal output terminal for outputting the output signal of the latch circuit.