Push-push oscillator circuit

摘要

The invention pertains to a push-push oscillator circuit (10) with a first oscillation branch with a first active device (12) and a first tank (16, 20) adapted to provide a signal having a fundamental frequency f0, a second oscillation branch with a second active device (14) and a second tank (18, 22) symmetrical to the first oscillation branch and adapted to provide a signal having the fundamental frequency f0. Output branches (24, 28, 50, 60) are coupled to the first oscillation branch and the second oscillation branch to provide signals having the second harmonic frequency 2f0 of the fundamental signal based on the signals having the fundamental frequency f0 and/or to provide signals having the fundamental frequency f0. The push-push oscillator circuit (10) further comprises at least one terminal branch (36, 58, 68, 78) with a terminal (42, 82, 94, 100) adapted to provide a component of a differential signal having the second harmonic frequency 2f0 or the fundamental frequency f0. The at least one terminal branch (36, 58, 68, 78) comprises a RF stub (44, 84) comprising a quarter-wavelength transmission line (46, 86, 102, 106) and a corresponding capacitor (48, 88, 104, 108) for a signal having the second harmonic frequency 2f0 or the fundamental frequency f0. The invention also pertains to a push-push oscillator circuit (10) having output branches (24, 28, 50, 60) coupled to the first oscillation branch and the second oscillation branch to provide signals having the fundamental frequency f0. One of the output branches (50) comprises two coupling inductors (52, 54) and a first fundamental frequency branch (58) having a first fundamental frequency terminal (94), the first fundamental frequency branch (58) being coupled in series with one of the coupling inductors (54), the two coupling inductors being coupled to each other in series via a first connection point. Another one of the output branches (60) comprises two coupling inductors (62, 64) and a second fundamental frequency branch (68) with a second fundamental frequency terminal (100), the second fundamental frequency branch (68) being coupled in series to one of the coupling inductors (54) of this output branch (6), and the two coupling inductors (62, 64) of this output branch (60) being coupled to each other in series via a second connection point. The push-push-oscillator circuit (10) is adapted to provide a differential signal having the fundamental frequency f0 at the first and second fundamental frequency terminals.