Abstract:
Certain aspects of the present disclosure generally relate to a voltage-controlled oscillator (VCO) that is configurable (e.g., in a dynamic manner) in multiple modes of operation (e.g., low/high-band modes). The VCO may include a resonant circuit coupled to a plurality of switches that may be used to adjust current flow within one or more inductive elements of the resonant circuit. By adjusting the current flow within the inductive elements, an inductance of the resonant circuit may be adjusted, which in turn adjusts a band of the VCO.
Abstract:
A digitally controlled oscillator (DCO) modulation apparatus and method provides a wideband phase-modulated signal output. An exemplary modulator circuit uses an oscillator in a phase-locked loop. The circuit receives a wrapped-phase input signal, unwraps the wrapped-phase input signal to generate an unwrapped-phase signal, and differentiates the unwrapped-phase signal. The wrapped-phase input signal and the differentiated unwrapped-phase signal are both injected into a feedback loop of the modulator circuit. The feedback loop may include a multi-modulus frequency divider with a frequency divisor that is temporarily incremented or decremented to cancel out abrupt phase jumps associated with the wrapped-phase to unwrapped-phase conversion.
Abstract:
The invention relates to a resonator circuit (100), the resonator circuit (100) comprising a transformer (101) comprising a primary winding (103) and a secondary winding (105), wherein the primary winding (103) is inductively coupled with the secondary winding (105), a primary capacitor (107) being connected to the primary winding (103), the primary capacitor (107) and the primary winding (103) forming a primary circuit, and a secondary capacitor (109) being connected to the secondary winding (105), the secondary capacitor (109) and the secondary winding (105) forming a secondary circuit, wherein the resonator circuit (100) has a common mode resonance frequency at an excitation of the primary circuit in a common mode, wherein the resonator circuit (100) has a differential mode resonance frequency at an excitation of the primary circuit in a differential mode, and wherein the common mode resonance frequency is different from the differential mode resonance frequency.
Abstract:
A transformer is described. The transformer includes a primary coil and a first secondary coil. A first coupling occurs between the first secondary coil and the primary coil. The transformer also includes a second secondary coil. A second coupling occurs between the second secondary coil and the primary coil. The first secondary coil is separated from the second secondary coil to prevent coupling between the first secondary coil and the second secondary coil. A first width of the first secondary coil is configured independently of a second width of the second secondary coil.
Abstract:
The present invention provides an injection locked frequency multiplier. The injection locked frequency multiplier comprises: an input stage, configured to receive an input signal having a first frequency, and generate a harmonic current; a resonant tank, configured to receive the generated harmonic current and flatten a phase response over a frequency band; and an output stage, configured to provide an output signal having a second frequency. The second frequency is a multiple of the first frequency. The resonant tank may be a high order resonant tank.
Abstract:
A method, an apparatus, and a computer program product are provided. The apparatus provides a VCO signal. The apparatus is a VCO. The apparatus includes a first transconductance circuit. The apparatus further includes a second transconductance circuit coupled with the first transconductance circuit. The second transconductance circuit has a first configuration/mode (e.g., CMOS configuration/mode) and a second configuration/mode (e.g., NMOS configuration/mode or PMOS configuration/mode). The second transconductance circuit is configured to couple an input of the second transconductance circuit to the first transconductance circuit in the first configuration/mode. The second transconductance circuit is configured to isolate the input of the second transconductance circuit from the first transconductance circuit in the second configuration/mode. The second transconductance circuit may include a first transistor and a second transistor, and the input may be a gate of each of the first transistor and the second transistor.
Abstract:
An oscillator (200, 300, 350) comprises a tank circuit (100), a first transistor (M1c) and a second transistor (M1r), and the second transistor (M1r) occupies an area of silicon that is smaller than an area of silicon occupied by the first transistor (M1c). A switching apparatus (Sw1...Sw14) selects either one of a first oscillator topology and a second oscillator topology, where in the first oscillator topology, the tank circuit (100) is coupled to the first transistor (M1c) in a first feedback configuration to provide feedback around the first transistor (M1c), and in the second oscillator topology, the tank circuit (100) is coupled to the second transistor (M1r) in a second feedback configuration that is different to the first feedback configuration to provide feedback around the second transistor (M1r).
Abstract:
The disclosed embodiments provide a system which starts up and shuts down a resonant oscillator circuit. During the start up process, a driving circuit uses a first clock signal to control a first phase output of the resonant oscillator circuit. At the same time, the driving circuit uses a second clock signal to control a second phase output of the resonant oscillator circuit, wherein the first and second clock signals have opposite phases. While the first and second phase outputs are being controlled, the system ramps up an input voltage, which is used to power the resonant oscillator circuit, wherein the ramping takes place across multiple initial oscillation periods. During the shut down process, the system shuts down the resonant oscillator circuit by ramping down the input voltage. After the input voltage has been ramped down, the system clamps the first and second phase outputs to a fixed voltage.