New LC oscillator topology in CMOS 0.18-μm technology

This paper presents a new inductance-capacitance (LC) oscillator topology. The circuit configuration proposed employs a single inductor for the LC resonator tank. The tank is connected to an NMOS cross-coupled pair with PMOS active load. A second NMOS cross-coupled pair is placed between the gates of the active loads to enhance the positive feedback without degrading the phase noise. The technology used for the design is a standard CMOS 0.18-mu m. Simulations are shown to compare the performance of the proposed topology, in terms of phase noise and power consumption, with the well-known complementary cross-coupled topology and the NMOS crosscoupled topology with active load.