Patent ID: 7038498

Claim:
A reference-voltage generating circuit for generating a voltage to supply the generated voltage as a reference voltage to an input circuit of an input/output circuit, said input/output circuit having an output circuit comprising: a first series circuit including a first transistor and a first resistor connected serially between a high-potential power supply and an input/output pin; a second series circuit including a second transistor and a second resistor connected serially between the input/output pin and a low-potential power supply; and control means for turning on the first and second transistors based upon a control signal at the time of a signal input from the input/output pin to said input circuit, thereby causing said first and second series circuits to operate a terminating circuit of a line connected to the input/output pin; wherein said reference-voltage generating circuit comprises a circuit for generating the reference voltage equal to a voltage, which prevails in the absence of an applied signal, at a connection node between the input/output pin and said first and second series circuits composing said terminating circuit in the input/output circuit.