Switching current source radio frequency oscillator

摘要

A novel and useful RF oscillator suitable for use in applications requiring ultra-low voltage and power. The oscillator structure, employing alternating current source transistors, combines the benefits of low supply voltage operation of conventional NMOS cross-coupled oscillators together with high current efficiency of the complementary push-pull oscillators. In addition, the 1/f noise upconversion is also reduced. The oscillator can be incorporated within a wide range of circuit applications, including for example a conventional phase locked loop (PLL), all-digital phase-locked loop (ADPLL), wireline transceiver circuits and mobile devices.

主权项

1. An oscillator circuit, comprising:
a lower pair of transistors; an upper pair of transistors, each transistor in said upper pair stacked on a respective transistor in said lower pair, a gate terminal of each transistor in said upper pair coupled with a respective gate terminal of transistors in said lower pair; an LC-tank circuit coupled between the gate terminals of the transistors in said upper pair and drain terminals of said lower pair, said LC-tank circuit operative to exhibit a passive voltage gain; and wherein said upper pair of transistors and said lower pair of transistors are operative to cause current through said LC-tank to reverse direction every half period.