RF CMOS$LC$-Oscillator With Source Damping Resistors

This letter proposes a new method to suppress the 1/f noise contribution of active devices in an oscillator using source damping resistors. The operational mechanism of the proposed source damping resistor method is analyzed through circuit simulation with a complementary LC-oscillator. The reduced 1/f noise leads to the phase noise improvement by suppressing 1/f noise up-conversion to phase noise. The measurement result shows that there is about 6.0dBc and 4.0dBc of phase noise improvement at 10kHz and 100kHz offset frequency with differential complementary LC-oscillator topology, respectively

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