| 摘要 |
PROBLEM TO BE SOLVED: To provide the image exclusion mixer circuit having a more excellent noise characteristic. SOLUTION: The mixer circuit 200 has an input stage 290, cross coupling phase splitters 292, 293 and mixer cores 294, 295. An input signal is given to an input terminal 220, a local oscillator signal is given to input terminals 230, 231, and an oscillation signal shifted by 90 deg. is given to input terminals 232, 233. An in-phase difference signal is outputted from output terminals 240, 241 and a quadrature phase signal is outputted from output terminals 242, 243. A phase splitter is made up of transistors(TRs) 202, 203, and 205, 206, which are biased by a level applied to a terminal 262. The mixer circuit 200 provides an excellent noise characteristic. A negative feedback inductor 280 reduces noise. Second harmonics of the local oscillator signal are cancelled by the phase splitter.
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