Qualcomm Incorporated

Texas Instruments Corporation

Icera, Inc.

Solti Peng

Wei Zhuo

Gurkanwal Singh Sahota

Abdellatif Bellaouar

Heng-Chih Lin

Chien-Chung Chen

Dirk Leipold

Yang Xu

Aristotele Hadjichristos

James Fred Salzman

Roger Brockenbrough

See Taur Lee

Junxiong Deng

Arul Balasubramaniyan

A power supply noise rejection circuit for functional circuits, such as a voltage controlled oscillator (VCO). The power supply noise rejection circuit includes an isolation transistor connected to a voltage supply for providing an output current and voltage substantially free of noise across the full frequency range. A current source, a diode connected reference transistor with resistance means connected between its gate and drain terminals, and a dummy circuit serially connected between the voltage supply and ground generate a bias voltage that is applied to the gate of the isolation transistor. The dummy circuit mimics the DC characteristics of the functional circuit such that the output current tracks with process and temperature variations. The isolation transistor and the reference transistor can have negative threshold voltages, and the circuit can include bleed means for drawing current from the gate of the reference transistor and isolation transistor.

Low supply regulator having a high power supply rejection ratio

A downconversion mixer includes a configurable gate or bulk bias voltage to allow calibration and correction of device offsets. Calibration may be performed on the configurable bias voltages to minimize IM2 distortion in the mixer. The techniques have minimal impact on voltage headroom, impose no requirement for a signal path to be phase-matched with a calibration path, and are particularly well-suited for passive mixers.

Offset correction for passive mixers

A complementary amplifier includes an NMOS transistor coupled to a PMOS transistor in a stacked configuration. The NMOS transistor and the PMOS transistor receive and amplify an input signal. The NMOS and PMOS transistors operate as a linear complementary amplifier and provide an output signal. The NMOS and PMOS transistors may have separate bias voltages, which may be selected to overlap the low-to-high and high-to-low transitions of the transconductances of these transistors. The width and length dimensions of the NMOS and PMOS transistors may be selected to match the change in input capacitance and the change in transconductance of the NMOS transistor in moderate inversion region with the change in input capacitance and the change in transconductance of the PMOS transistor in moderate inversion region. The complementary amplifier may have an approximately constant total input capacitance and an approximately constant total transconductance over a range of voltages.

High-linearity complementary amplifier

A noise isolation passive mixing apparatus is designed to mitigate noise contribution from intermediate frequency (IF) filters and amplifiers in a radio frequency translation stage. Common-gate configuration devices are inserted between passive mixer output and input of a transimpedance amplifier. In this way, circulation of the input-referred noise of the transimpedance amplifier is decreased, because of the relatively high output impedance of the common-gate devices, and the noise figure of the mixing apparatus can be improved. Since the radio frequency signal still sees low impedance, a radio frequency transconductance (RF gm) stage can be removed from the mixing apparatus, reducing current consumption. A double-balanced mixing apparatus with this general architecture may be implemented in a 0.18 micrometer CMOS technology and used in a low-IF global positioning system operating at 1.575 GHz, in an access terminal of a cellular communication system, and in other systems.

Apparatus and methods for downconverting radio frequency signals

A method according to one embodiment includes using a quadrature set of local oscillator signals having duty cycles of substantially less than fifty percent to perform a mixing operation on a radio-frequency current signal. Other embodiments include using a quadrature set of local oscillator signals having duty cycles of less than twenty-five percent.

Systems, methods, and apparatus for frequency conversion

A frequency converter according to one embodiment includes a quadrature pair of passive mixers whose input terminals are coupled to a differential radio-frequency input via the channel regions of transistors that are arranged to operate in the saturation region.

A transformer system includes a package substrate having a surface. A plurality of electrically conductive pads are arranged in spaced apart relationship relative to each other on the substrate surface. A first winding is defined by a first electrically conductive path between a first input and a first output, the first electrically conductive path including at least one wire connected between at least one first pad pair of the electrically conductive pads. At least one electrically conductive pad of each first pad pair is at the substrate surface. A second winding is defined by a second electrically conductive path between a second input and a second output, the second electrically conductive path including at least one wire connected between at least one second pad pair of the electrically conductive pads. At least one electrically conductive pad of each second pad pair is at the substrate surface. The first and second electrically conductive paths are proximal each other to achieve a magnetic field coupling between the first and second windings so as to form a transformer.

System and method for implementing transformer on package substrate

According to one embodiment of the invention, an amplifier includes a gate bias circuit operable to generate a gate bias voltage and a common gate amplifier that includes a transistor having a gate biased by an output of the gate bias circuit and also having a source connected to an inductor for providing a path to ground for direct current flowing through the transistor. According to another embodiment of the invention, a method for amplifying a signal by an amplifier includes generating a gate bias voltage indicative of a difference between a reference voltage and an output voltage of the amplifier, biasing the gate of the common-gate amplifier with the gate bias voltage, and blocking, by a passive device, alternating current signals from flowing from the source of the transistor to ground.

Method and system for amplifying a signal

A hybrid Nyquist thermometer and sigma delta digital to analog converter is presented. The digital input signal is divided into most significant bits and least significant bits. The most significant bits are converted to a thermometer code. A thermometer element array is controlled by the thermometer code. A fractional value is calculated from the least significant bits and used to dither the first unexercised array element in order to get finer resolution with guaranteed monotonicity.

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Plano, TX, United States of America

Solti Peng