Analysis and Design of a 195.6 dBc/Hz Peak FoM P-N Class-B Oscillator With Transformer-Based Tail Filtering

作者：Garampazzi Marco^*; Mendes Paulo M; Codega Nicola; Manstretta Danilo; Castello Rinaldo

来源：IEEE Journal of Solid-State Circuits, 2015, 50(7): 1657-1668.

DOI：10.1109/JSSC.2015.2413851

• Class-B
• class-C
• class-F
• distributed oscillator
• figure of merit (FoM)
• oscillator
• phase noise
• voltage-controlled oscillator (VCO)

A complementary p-n class-B oscillator with two magnetically coupled second harmonic tail resonators is presented and compared to an N-only reference one. An in depth analysis of phase noise, based on direct derivation of the Impulse Sensitivity ISF), provides design insights on the optimization of the tail resonators. In principle the complementary p-n oscillator has the same optimum Figure of Merit (FoM) of the N-only at half the voltage swing. At a supply voltage of 1.5 V, the maximum allowed oscillation amplitude of the N-only is constrained, by reliability considerations, to be smaller than the value that corresponds to the optimum FoM even when 1.8 V thick oxide transistors are used. For an oscillation amplitude that ensures reliable operation and the same tank, the p-n oscillator achieves a FoM 2 to 3 dB better than the N, only depending on the safety margin taken in the design. After frequency division by 2, the p-n oscillator has a measured phase noise that ranges from -150.8 to -151.5 dBc/Hz at 10 MHz offset from the carrier when the frequency of oscillation is varied from 7.35 to 8.4 GHz. With a power consumption of 6.3 mW, a peak FoM of 195.6 dBc/Hz is

• 出版日期2015-7