US 6,549,082 B2 · High frequency oscillator

Abstract

The high frequency oscillator comprises a reference oscillator, a phase-locked loop circuit with a phase frequency detector, a charge pump, a ring oscillator and a divider, the reference oscillator being coupled to the phase frequency detector for frequency control. The ring oscillator is a symmetrical delay cell oscillator containing two amplifiers with a dual output stage for providing I/Q output signal generation. The reference oscillator works in the range of 1.25-1.5 GHz and is a Colpitts type digital controlled frequency synthesizer with an external tank circuit for providing a low phase noise, and the dividing factor of the divider is four for providing a tuned output range of 5 to 6 GHz. The phase-locked loop circuit is integrated together with the reference oscillator into an integrated circuit, using advantageously a BICMOS Silicon/Germanium process, which is well suited for RF applications.

Claims5

Dependent claims

High frequency oscillator comprising a reference oscillator and a phase locked-loop circuit with

a phase-frequency detector,
a ring oscillator, being coupled via a divider to said phase-frequency detector,
a charge pump, being coupled between said phase-frequency detector and said ring oscillator,
said reference oscillator being coupled to said phase-frequency detector for frequency control,
said ring oscillator being a symmetrical delay cell oscillator comprising two delay cell amplifiers, wherein said charge pump comprises a current source with two pnp-transistors and a common current source, both being coupled to a differential amplifier, and the current of said current source is controlled by a reference voltage to provide in each of said pnp-transistors half of the current of said common current source.

2 more elements

Dependencies are inferred from the claim text.

High frequency oscillator

Life of this patent

High frequency oscillator

Life of this patent

Abstract

Claims5