| 摘要 |
PROBLEM TO BE SOLVED: To provide a mixer circuit preventing deterioration of an NF characteristic by suppressing influence of noise. SOLUTION: High-frequency signals RFin+, RFin- are inputted into first and second input ends 11a, 11b of a double balanced mixer. Local oscillation signals LOin+, LOin- are supplied to third and forth input ends 11c, 11d. A signal is outputted from first and second output ends OUT+, OUT-. A bias voltage generating circuit 12 is connected to the third and forth input ends so as to supply bias voltage to the local oscillation signals. First and second resistances 13, 14 are connected between the first and second output ends, and the ground. A differential amplifier 18 amplifies difference between a variable component of common mode voltage output from the first and second output ends of the mixer 11, and reference voltage, so as to supply the difference to the third and forth input ends. COPYRIGHT: (C)2008,JPO&INPIT
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