3.3-mA 2.8-GHz bufferless LC oscillator directly driving a 10-mm on-chip clock distribution line

<p>A bufferless <i>LC</i> oscillator can potentially offer an attractive solution for low-power, high-speed clock distribution due to the absence of repeaters on the clock distribution line and utilization of <i>LC</i> resonance. However, conventional bufferless <i>LC</i> oscillators suffer from a fundamental tradeoff between the frequency and power consumption due to their high-frequency sensitivity. In this paper, we have introduced a low-frequency sensitivity bufferless <i>LC</i> oscillator that is directly connected to a 10-mm on-chip clock distribution line in the TSMC 0.18-µm 1-Poly 6-Metal CMOS technology. The core area of the <i>LC</i> oscillator is only 270 × 280 µm². The measurement results show that a 2.8-GHz oscillation frequency, 3.3-mA current consumption, and −112.8 dBc/Hz phase noise at 1 MHz offset can be achieved.</p>