| 摘要 |
PROBLEM TO BE SOLVED: To obtain a differential terminating resistance adjusting circuit capable of reducing cost of a transmission system and a substrate mounting area by providing a built-in input terminating resistor in a semiconductor device. SOLUTION: The circuit has a reference current generating section 40 for outputting a fairly constant reference current Iref, a reference voltage generating section 10 for outputting fairly constant voltages VrefH, VrefL, a replica resistance generating section 30 supplied with the reference current Iref to output voltage drops Va, Vb, a control voltage generating section 20 for outputting control voltages Vcont1, Vcont2 on the basis of the reference voltages VrefH, VrefL and the control voltage drops Va, Vb, and an original resistance generating section 50 being built in a receiver side device 2 and connected to an input terminal. The resistance values of the sections 30, 50 are adjusted by the control voltage Vcont1, Vcont2. COPYRIGHT: (C)2004,JPO
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