Abstract:
An inductor circuit includes a pair of inductors connected in parallel with each other and a switch for turning on and off electric power to one of the pair of inductors. The inductance of the inductor circuit can be varied and the quality factor Q can be improved. Further, RF circuits employing the inductor circuit can generate an intended operating frequency.
Abstract:
Circuit (1) of a voltage controlled oscillator comprising: - a bridge structure including two cross-coupled transistors of N type (M 3 , M 4 ) and two cross-coupled transistors of P type (M 5 , M 6 ); - a current mirror (3) connected to the two cross-coupled transistors of N type (M 3 , M 4 ) and arranged to generate a bias current (I B ) for the circuit (1); - an LC resonator (2) placed in parallel between the two cross-coupled transistors of N type (M 3 , M 4 ) and the two cross-coupled transistors of P type (M 5 , M 6 ). The circuit (1) is characterised in that the LC resonator (2) comprises: two pairs of differential inductors (L 1 , L 2 ) mutually coupled by means of a mutual inductance coefficient (M), each pair comprising a first inductor (L 1 ) arranged on a respective branch (10a) of an external loop, and a second inductor (L 2 ) arranged on a respective branch (12a) of an internal loop; a first varactor (C v33 ) connected to a common node (A) and to a first branch (12a) of the internal loop; a second varactor (C v33 ) connected to the common node (A) and to a second branch (12a) of the internal loop.
Abstract:
PROBLEM TO BE SOLVED: To provide an LC resonance oscillation circuit which has a wide variable range of the frequency with small variance of Q, does not require external parts, and can reduce the chip size, and a semiconductor integrated circuit (high frequency IC) for communication use in which the LC resonance oscillation circuit is built-in. SOLUTION: In the LC resonance oscillation circuit, a capacitance element (C2) and a switch element (SW1) are parallel connected between both terminals of a secondary inductance element (L2) which is arranged facing an inductance element (L1) that constitutes the LC resonance circuit to be mutually inductively coupled. When the switch element is OFF, the capacitance element is connected between both terminals of the secondary inductance element, resulting to increase the equivalent inductance, and when the switch element is ON, both terminals of the secondary inductance element is short-circuited, resulting to decrease the equivalent inductance. COPYRIGHT: (C)2007,JPO&INPIT
Abstract:
PROBLEM TO BE SOLVED: To provide a variable inductor having little deterioration in a quality factor, and an oscillator and information equipment each using the variable inductor. SOLUTION: An inductance control circuit 41 composed of a reactive element with a variable element value, for example, variable capacitance is connected to a sub-inductor L2 magnetically coupled to a main inductor L1 through a mutual inductance M. An inductance control terminal VLC for receiving a control signal for changing a capacitance value of the variable capacitance is provided in the inductance control circuit 41. By changing the capacitance value by the control signal, the inductance of the main inductor is changed. COPYRIGHT: (C)2006,JPO&NCIPI
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:
An inductor layout (200, 300, 400) comprising a first inductor (210, 310, 410) and a second inductor (220, 320, 420). The first and second inductors (210, 310, 410; 220, 320, 420) are electrically and magnetically independent inductors concentrically arranged on an integrated circuit 800. At least one of the first and second inductors (210, 310, 410; 220, 320, 420) is a multi-loop inductor with a first axis (226a, 316a, 326a, 416a, 426a) of symmetry.
Abstract:
The invention relates to a voltage-controlled oscillator with an LC resonant circuit, especially for producing integrated voltage-controlled oscillators for the lower GHz range. The aim of the invention is to provide a voltage-controlled oscillator with an LC resonant circuit with which a continuous frequency tuning across a wide range of frequencies can be achieved with only little phase noise or phase jitter. To this end, the voltage-controlled oscillator with an LC resonant circuit with at least one inductivity can be connected to a further inductivity in periodic parallel and/or in series via a switch device that is actuated by the oscillator frequency, one control input of the switch device being connected to a variable direct current. The ratio of the duration of the conductive state and the duration of the non-conductive state of the switch devices can be modified within an oscillation period of the oscillator depending on the value of the control voltage. Corresponding to the ratio of the duration of the conductive state and the duration of the non-conductive state of the switch devices within one oscillation period of the oscillator the time-averaged, effective inductivity can be modified depending on the value of the control voltage.
Abstract:
A voltage controlled oscillator (VCO) is disclosed. The VCO includes an active device. The VCO comprises an active device, wherein the active device further includes an n-type transistor having a drain, gate and bulk; a p-type transistor having a drain, gate and bulk. The n-type transistor and the p-type transistor share a common source. The active device further includes a first capacitor coupled between the gate of n-type transistor and the gate of p-type transistor; a second capacitor coupled between the drain of the n-type transistor and the drain of p-type transistor; and a third capacitor coupled between the bulk of n-type transistor and the bulk of p-type transistor. The VCO includes a tuning block coupled to the common source to form a common gate amplifier and at least one tuning element coupled to the active device for changing the overall capacitance of the VCO.