Patent ID: 7969207

Claim:
An input circuit, comprising: a first buffer circuit that includes an output coupled to an output signal terminal of the input circuit, and an input coupled to an input signal terminal of the input circuit; a second buffer circuit; a third buffer circuit; a first differential amplification circuit that includes a first input coupled to a first external power source terminal, a second input coupled to an output of the second buffer circuit, and an output coupled to an input of the second buffer circuit; a second differential amplification circuit that includes a first input coupled to a second external power source terminal, a second input coupled to an output of the third buffer circuit, and an output coupled to an input of the third buffer circuit; a first resistance that includes one end coupled to the output of the first differential amplification circuit, and another end coupled between the input signal terminal the input circuit and the input of the first buffer circuit; and a second resistance that includes one end coupled to the output of the second differential amplification circuit, and another end coupled between the input signal terminal of the input circuit and the input of the first buffer circuit.