Patent ID: 7915967

Claim:
A frequency-tunable arrangement comprising: a resonance circuit having a capacitive part that is tunable throughout a capacitance range; and a plurality of amplifiers coupled to the resonance circuit so as to form an oscillation loop, at least one of the amplifiers being a switchable amplifier that is switchable between an active state and an idle state so as to cause a capacitance variation in parallel to the capacitive part of the resonance circuit, the capacitance variation substantially corresponding to the capacitance range throughout which the capacitive part can be tuned, wherein the switchable amplifier comprises a field-effect transistor in a common-source configuration, the field-effect transistor having a gate and a drain that are coupled in parallel to the capacitive part of the resonance circuit, wherein at least one of the amplifiers is a basic amplifier that comprises a field-effect transistor in a common-source configuration, the field-effect transistor having a gate and a drain that are coupled in parallel to the capacitive part of the resonance circuit, the field-effect transistor of the basic amplifier having a width-over-length ratio that is at least an order of magnitude greater than the width-over-length ratio of the field-effect transistor of the switchable amplifier.