CMOS VCO WITH IMPLICIT COMMON-MODE RESONANCE

摘要

A circuit for an oscillator with common-mode resonance includes a first oscillator circuit and a second oscillator circuit coupled to the first oscillator circuit. Each of the first oscillator circuit or the second oscillator circuit includes a tank circuit, a cross-coupled transistor pair, and one or more capacitors. The tank circuit is formed by coupling a first inductor with a pair of first capacitors. The cross-coupled transistor pair is coupled to the tank circuit, and one or more second capacitors are coupled to the tank circuit and the cross-coupled transistor pair. Each of the first oscillator circuit or the second oscillator circuit allows tuning of a respective common mode (CM) resonance frequency (Fcm) to be at twice a respective differential resonance frequency (FD).;DM——ITS 62683970-1.093986 0453

主权项

1. A circuit for an oscillator with common-mode resonance, the circuit comprising:
a first oscillator circuit comprising a first cross-coupled transistor pair; and a second oscillator circuit comprising a second cross-coupled transistor pair coupled to the first oscillator circuit via a joint tank circuit, wherein at least one of the first oscillator circuit or the second oscillator circuit the joint tank circuit comprises: a differential inductor including first and second pair of nodes, each of the first and second pair of nodes coupled with a pair of first capacitors to ground potential; and a pair of second capacitors, one capacitor of the pair of second capacitors being coupled to between the first pair of nodes of the differential inductor that is coupled to drain nodes the first cross-coupled transistor pair, and another capacitor of the pair of second capacitors being coupled between the second pair of nodes of the differential inductor that is coupled to drain nodes the second cross-coupled transistor pair.