| 摘要 |
PROBLEM TO BE SOLVED: To provide a quadrature mixer circuit capable of suppressing variations in secondary distortion while suppressing a consumed current, and to provide a semiconductor integrated circuit for RF communication. SOLUTION: A phase of a local signal given to bases of transistors QI 3 to QI 6 in the quadrature mixer circuit differs from a phase of a local signal given to bases of transistors QQ 3 to QQ 6 by 90 degrees, and even when the amplitude of the local signals is greater, since the interference between the signals can be suppressed by resistors RI 3, 4 and resistors RQ 3, 4 and capacitors C 1, 2, and the capacitors C 1, 2 prevent a DC bias from being changed, variations in the secondary distortion can be suppressed. Further, since the capacitors C 1, 2 compose current outputs from a differential circuit comprising the transistors QI 1, 2 and a resistor R 5 and a differential circuit comprising the transistors QQ 1, 2 and the resistor R 5, the consumed current can also be reduced. COPYRIGHT: (C)2007,JPO&INPIT
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