Abstract: A semiconductor device comprises synthesized frequency generation logic arranged to receive a reference signal, and to provide an output frequency signal. The synthesized frequency generation logic comprises divider logic arranged to receive the reference signal and to generate a divided signal comprising a frequency with a period equal to N times that of the reference signal. The synthesized frequency generation logic is further arranged to generate the synthesized frequency signal comprising a frequency with a period equal to 1/M that of the divided signal. The synthesized frequency generation logic comprises or is operably coupled to decision logic module and comprises or is operably coupled to a switching logic module such that the decision logic module is arranged to determine whether a near-integer spur arises in using the synthesized frequency signal, and configures the switching logic module to select the synthesized frequency signal in response thereto.

Abstract: A semiconductor device comprises synthesized frequency generation logic arranged to receive a reference signal, and to generate a synthesized frequency signal from the reference signal. The synthesized frequency generation logic comprises programmable divider logic arranged to receive the reference signal and to generate a divided signal comprising a frequency with a period substantially equal to N times that of the reference signal, where N comprises a programmable integer value. The synthesizer frequency generation logic is arranged to generate the synthesized frequency signal comprising a frequency with a period substantially equal to 1/M that of the divided signal, where M comprises a further programmable integer value.

Abstract: A wireless communication unit comprises a frequency generation circuit employing a phase locked loop (PLL) circuit comprising a voltage controlled oscillator having a modulation port for directly modulating a signal output from the voltage controlled oscillator. The voltage controlled oscillator is operably coupled to at least one switch and a capacitor bank comprising one or more varactors. A controller is arranged to switch in one or more varactors associated with the modulation port of the phase locked loop circuit to provide an inverse cubic relationship to the direct modulated signal. In addition, or alternatively, the phase locked loop (PLL) circuit may comprise a voltage controlled oscillator having a tuning port for controlling a frequency of a signal output from the voltage controlled oscillator. The controller here is arranged to switch in one or more varactors associated with the tuning port of the phase locked loop circuit in an inverse square relationship.

Abstract: An integrated circuit comprises a digital phase-locked loop for a wireless communications unit. The digital phase-locked loop comprises a voltage controlled oscillator and a digital tuning subsystem. An input of the digital tuning subsystem receives the output signal from the voltage controlled oscillator, and an output of the digital tuning subsystem is supplied to the voltage controlled oscillator. A digital voltage generator is adapted to store at least two predetermined forcing voltages. The digital voltage generator is adapted to select one of the at least two predetermined forcing voltages, in dependence on a current temperature value, and to supply it as a forcing voltage to an input of the voltage controlled oscillator, prior to the phase locked loop achieving lock. A wireless communication unit and a method of tuning a phase-locked loop are also provided.

Abstract: A semiconductor device comprises synthesized frequency generation logic arranged to receive a reference signal, and to provide an output frequency signal. The synthesized frequency generation logic comprises divider logic arranged to receive the reference signal and to generate a divided signal comprising a frequency with a period equal to N times that of the reference signal. The synthesized frequency generation logic is further arranged to generate the synthesized frequency signal comprising a frequency with a period equal to 1/M that of the divided signal. The synthesized frequency generation logic comprises or is operably coupled to decision logic module and comprises or is operably coupled to a switching logic module such that the decision logic module is arranged to determine whether a near-integer spur arises in using the synthesized frequency signal, and configures the switching logic module to select the synthesized frequency signal in response thereto.

Abstract: A semiconductor device comprises synthesized frequency generation logic arranged to receive a reference signal, and to generate a synthesized frequency signal from the reference signal. The synthesized frequency generation logic comprises programmable divider logic arranged to receive the reference signal and to generate a divided signal comprising a frequency with a period substantially equal to N times that of the reference signal, where N comprises a programmable integer value. The synthesizer frequency generation logic is arranged to generate the synthesized frequency signal comprising a frequency with a period substantially equal to 1/M that of the divided signal, where M comprises a further programmable integer value.

Abstract: A wireless communication unit comprises a frequency generation circuit employing a phase locked loop (PLL) circuit comprising a voltage controlled oscillator having a modulation port for directly modulating a signal output from the voltage controlled oscillator. The voltage controlled oscillator is operably coupled to at least one switch and a capacitor bank comprising one or more varactors. A controller is arranged to switch in one or more varactors associated with the modulation port of the phase locked loop circuit to provide an inverse cubic relationship to the direct modulated signal. In addition, or alternatively, the phase locked loop (PLL) circuit may comprise a voltage controlled oscillator having a tuning port for controlling a frequency of a signal output from the voltage controlled oscillator. The controller here is arranged to switch in one or more varactors associated with the tuning port of the phase locked loop circuit in an inverse square relationship.