Abstract: A technique for tuning a ladder-shaped inductor that achieves a finer tuning resolution by severing one or more shorts, skipping the severing of one or more shorts, and severing one or more subsequent shorts within the ladder-shaped inductor. This technique can be applied to a voltage-controlled oscillator using a differential or single-ended ladder-shaped inductor as part of the resonant circuit. Within an oscillator, such a technique provides for a more precise modulation of the effective inductance of the ladder-shaped inductor, which enables an improved tuning resolution of the operating frequency of the oscillator.

Abstract: Apparatus are provided for voltage-controlled oscillators and related systems. An exemplary voltage-controlled oscillator includes an active-circuit arrangement that facilitates generation of an oscillating signal, and a resonator arrangement capacitively coupled to the active-circuit arrangement to influence an oscillation frequency of the oscillating signal based on a difference between a first control voltage and a second control voltage.

Abstract: Apparatus are provided for voltage-controlled oscillators (VCOs) and related systems. An exemplary VCO includes an active-circuit arrangement employing cross-coupled amplifying elements that facilitate generation of an oscillating signal, plus a resonator arrangement capacitively coupled via resonator terminals to primary terminals of the active-circuit arrangement, to influence an oscillation frequency of the oscillating signal based on a difference between control voltages applied to first and second control terminals of the resonator arrangement. When employing bipolar amplifying elements their control terminals are cross-coupled to the opposing resonator terminals. VCO output may be taken from the primary terminals or from the resonator terminals.

Abstract: Apparatus are provided for voltage-controlled oscillators and related systems. An exemplary voltage-controlled oscillator includes a first variable capacitance element, a second variable capacitance element coupled between the first control voltage node and the third node, and an inductive element coupled between the variable capacitance elements to provide an inductance between the variable capacitance elements at an oscillation frequency of an oscillating signal at an output node. The first variable capacitance element is coupled between a first control voltage node and the output node, the second variable capacitance element is coupled to the first control voltage node, and a second inductive element is coupled between the second variable capacitance element and a second control voltage node.

Abstract: Apparatus are provided for voltage-controlled oscillators and related systems. An exemplary voltage-controlled oscillator includes a first variable capacitance element, a second variable capacitance element coupled between the first control voltage node and the third node, and an inductive element coupled between the variable capacitance elements to provide an inductance between the variable capacitance elements at an oscillation frequency of an oscillating signal at an output node. The first variable capacitance element is coupled between a first control voltage node and the output node, the second variable capacitance element is coupled to the first control voltage node, and a second inductive element is coupled between the second variable capacitance element and a second control voltage node.

Abstract: An oscillator circuit is provided for generating an oscillating signal. The oscillator circuit includes a transistor circuit, a resonator circuit, and first and second transmission line open stubs. The transistor circuit is coupled to a first node and a second node of the oscillator circuit. The transistor circuit is for facilitating oscillation of the oscillating signal. The resonator circuit is coupled to the first node and the second node, and includes an inductance and a capacitance. The first and second transmission line open stubs are coupled to the first and second nodes, respectively. The first and second transmission line open stubs have a length substantially equal to a quarter wavelength of a second harmonic of the oscillating signal, and are for removing the second harmonic from the oscillating signal. In another embodiment, first and second half wave AC shorted stubs are used to remove the second harmonic from the oscillating signal.

Abstract: Apparatus are provided for voltage-controlled oscillators (VCOs) and related systems. An exemplary VCO includes an active-circuit arrangement employing cross-coupled amplifying elements that facilitate generation of an oscillating signal, plus a resonator arrangement capacitively coupled via resonator terminals to primary terminals of the active-circuit arrangement, to influence an oscillation frequency of the oscillating signal based on a difference between control voltages applied to first and second control terminals of the resonator arrangement. When employing bipolar amplifying elements their control terminals are cross-coupled to the opposing resonator terminals. VCO output may be taken from the primary terminals or from the resonator terminals.

Abstract: Apparatus are provided for voltage-controlled oscillators and related systems. An exemplary voltage-controlled oscillator includes an active-circuit arrangement that facilitates generation of an oscillating signal, and a resonator arrangement capacitively coupled to the active-circuit arrangement to influence an oscillation frequency of the oscillating signal based on a difference between a first control voltage and a second control voltage.

Abstract: A structure that reduces signal cross-talk through the semiconductor substrate for System-On-Chip (SOC) (2) applications, thereby facilitating the integration of digital circuit blocks (6) and analog circuit blocks (8) onto a single IC. Cross-circuit interaction through a substrate (4) is reduced by strategically positioning the various digital circuit blocks (6) and analog circuit blocks (8) in an isolated wells (10), (12), (16) and (20) over a resistive substrate (4). These well structures (10), (12), (16), and (20) are then surrounded with a patterned low resistivity layer (22) and optional trench region (24). The patterned low resistivity region (22) is formed below wells (10) and (12) and functions as a low resistance AC ground plane. This low resistivity region (22) collects noise signals that propagate between digital circuit blocks (6) and analog circuit blocks (8).

Abstract: A structure that reduces signal cross-talk through the semiconductor substrate for System-On-Chip (SOC) (2) applications, thereby facilitating the integration of digital circuit blocks (6) and analog circuit blocks (8) onto a single IC. Cross-circuit interaction through a substrate (4) is reduced by strategically positioning the various digital circuit blocks (6) and analog circuit blocks (8) in an isolated wells (10), (12), (16) and (20) over a resistive substrate (4). These well structures (10), (12), (16), and (20) are then surrounded with a patterned low resistivity layer (22) and optional trench region (24). The patterned low resistivity region (22) is formed below wells (10) and (12) and functions as a low resistance AC ground plane. This low resistivity region (22) collects noise signals that propagate between digital circuit blocks (6) and analog circuit blocks (8).