Patent ID: 7342462
Filing Date: 2008-03-11
Classification: H03B,H03L

Abstract:
1. An oscillator arrangement, comprising: two voltage controlled oscillators, each said oscillator producing an output signal, wherein the two oscillators are cross coupled by two couplers, each of the couplers controllably inserting a portion of a respective said output signal from one of said oscillators into a summing node coupled to an input of the other of said oscillators according to a coupling coefficient, and wherein the oscillators produce respective said output signals synchronously with a phase difference; two pairs of bias current controls, one pair of said bias current controls being coupled in series with respective ones of the oscillators for adjusting a tail current through said oscillators, and the other pair of said bias current controls being coupled in series with respective said couplers and adjusting the coupling coefficient at each of the couplers; a control coupled to the bias current controls, wherein the control is operable upon a change in coupling coefficient at the couplers to produce an opposite change in the tail current through the oscillators, increasing one when decreasing the other, and vice versa.