Abstract:
A dual-band voltage controlled oscillator (VCO) includes: a first oscillator circuit including a first inductor; a second oscillator circuit including a second inductor; a first mode switch configured to electrically connect or disconnect a first output terminal of the first oscillator circuit and a first output terminal of the second oscillator circuit; a second mode switch configured to electrically connect or disconnect a second output terminal of the first oscillator circuit and a second output terminal of the second oscillator circuit; a third mode switch configured to electrically connect or disconnect a first terminal of the first inductor and a first terminal of the second inductor; and a fourth mode switch configured to electrically connect or disconnect a second terminal of the first inductor and a second terminal of the second inductor.
Abstract:
Die Erfindung betrifft einen Hochfrequenz-Oszillator (1) mit einem elektrischen Schwingkreis (2), eine Hochfrequenz-Schweißanlage sowie ein Verfahren zur Frequenzregelung mit einem Hochfrequenz-Oszillator insbesondere in einer Hochfrequenz-Schweißanlage. Dabei weist der elektrische Schwingkreis (2) mindestens ein elektronisches Bauelement (3) mit einer Induktivität und mindestens einen Kondensator (4) mit einer Kapazität auf. Um eine schnelle und verschleißfreie Regelung der Frequenz des elektrischen Schwingkreises zu ermöglichen, ist dem elektronischen Bauelement (3) mindestens eine zusätzliche Magnetspule (6) zugeordnet, mit der die Induktivität des elektronischen Bauelements (3) elektronisch beeinflussbar ist.
Abstract:
An apparatus for generating an oscillating output signal includes an inductive-capacitive (LC) circuit and a current tuning circuit. The LC circuit includes a primary inductor and a varactor coupled to the primary inductor. A capacitance of the varactor is responsive to a voltage at a control input of the varactor. The current tuning circuit includes a secondary inductor and a current driving circuit coupled to the secondary inductor. The current driving circuit is responsive to a current at a control input of the current driving circuit. An effective inductance of the primary inductor is adjustable via magnetic coupling to the secondary inductor, and a frequency of the oscillating output signal is responsive to the effective inductance of the primary inductor and to the capacitance of the varactor.
Abstract:
Techniques for providing transformer-based CMOS oscillators capable of operation with low voltage power supplies. In an exemplary embodiment, an LC tank is provided at the drains of a transistor pair, and the inductance of the LC tank is mutually magnetically coupled to an inductance between the gates of the transistor pair. A separate complementary transistor pair is also coupled to the LC tank. A further exemplary embodiment provides an LC tank at the gates of a transistor pair, as well as for three-way coupling amongst a tank inductance, an inductance between the gates of the transistor pair, and an inductance between the gates of a complementary transistor pair.
Abstract:
An electronic device (2) is made from a first substrate (22) with device circuitry (32) including an inductor (42) and a second substrate (24) with inductance adjustment circuitry (60) including a number of other inductors (62). The substrates (22, 24) are assembled together to be opposite one another. The other inductors (62) are arranged to provide a selection of different mutual inductance relationships relative to the inductor (42). These relationships are selectable during operation of the device to provide a variable inductance in the device circuitry (32).
Abstract:
An improved inductive reactance to frequency converter circuit (10) for producing an output signal whose frequency is capable of variation in response to a variable input inductance or inductive reactance (30) comprises differential gain means (42) and an improved resonant circuit (20) whose resonance frequency determines the frequency of the output signal. The improved resonant circuit (20) comprises a capacitance element (60, 62) and a transformer (64) whose primary coil (70) is capable of being connected to the variable inductive input reactance (30) and whose secondary coil (68) is connected in parallel with the capacitive element (60, 62) for enabling relatively small changes in the variable input inductive reactance (30) to be measured as relatively large changes in the resonance frequency of the resonant circuit (20).
Abstract:
Certain aspects of the present disclosure provide techniques and apparatus for generating multiple oscillating signals. One example circuit generally includes a first voltage-controlled oscillator (VCO) having a first inductor and a second VCO having a second inductor in parallel with a third inductor, wherein the second and third inductors are disposed inside a loop of the first inductor and may behave as a magnetic dipole. The loop of the first inductor may be symmetrical, and a combined geometry of loops of the second and third inductors may be symmetrical. The coupling coefficient (k) between the first inductor and a combination of the second and third inductors may be small (e.g., k
Abstract:
A tunable oscillator circuit is disclosed. The tunable oscillator circuit includes an inductor/capacitor (LC) tank circuit comprising a primary inductor coupled in parallel with a first capacitor bank. The LC tank resonates to produce an oscillating voltage at a frequency. The tunable oscillator circuit also includes a 90 degree phase shift buffer coupled to the LC tank and a transconductor. The transconductor is coupled to the 90 degree phase shift buffer and a secondary inductor. The tunable oscillator circuit also includes a secondary inductor that is inductively coupled to the primary inductor and receives a gain-scaled oscillating current from the transconductor. By changing the transconductance, the gain-scaled oscillating current in the secondary inductor will change, thus the effective primary inductance and the oscillation frequency can be tuned.
Abstract:
A VCO includes a transformer-based resonator that has a first LC tank and a second LC tank. The resonator has an even resonant mode and an odd resonant mode. The VCO further includes an active transconductance network that is coupled to a two-terminal port of the first tank and is also coupled to a two-terminal port of the second tank. A first terminal of the port of the first tank is capacitively coupled to a first terminal of the port of the second tank. A second terminal of the port of the first tank is capacitively coupled to a second terminal of the port of the second tank. The active transconductance network causes the resonator to resonate in a selectable one of the even and odd resonant modes depending on a digital control signal. The VCO is fine tuned by changing the capacitances of capacitors of the tanks.