| 摘要 |
PROBLEM TO BE SOLVED: To provide an output circuit which can suppress change of a common mode voltage of a differential output signal at pre-emphasis time and de-emphasis time, and correspond to change of high speed common mode voltage. SOLUTION: The output circuit includes: a first differential pair of transistors which is driven by a first current source, and differentially receives input signals, and whose output pair are connected to differential output terminals; and a second differential pair of transistors which is driven by a second current source, and differentially receives first control signals, and whose output pair are connected to the differential output terminals. A load resistor element pair are connected between the differential output terminals and a power supply. Furthermore, the output circuit includes a third differential pair of transistors which are driven by a third current source, and differentially receive second control signals, and whose output pair are connected to one output terminal of the differential output terminals and the power supply; and a fourth differential pair of transistors which are driven by a fourth current source, and differentially receives third control signals, and whose output pair are connected to the power supply and another output terminal of the differential output terminals. COPYRIGHT: (C)2011,JPO&INPIT
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