Skyworks Solutions, Inc.

Conexant Systems, Inc.

Solantro Semiconductor Corp.

Philsar Electronics, Inc.

Christian Cojocaru

Mark M Cloutier

Florinel G Balteanu

Tudor Lipan

David Steven Ripley

Paul T DiCarlo

Atiqul Baree

Igor Miletic

Thomas A D Riley

Norman M Filiol

Theodore Varelas

Luc Lussier

Michael Sawires

Antoine Paquin

A Galvanically Isolated Amplifier (GIA) includes an isolation barrier to galvanically isolate high voltage circuitry from low voltage circuitry. The high voltage circuitry has at least two voltage supply rails, with the voltage supply rail closest to ground potential at a first potential relative to the ground potential. The low voltage circuitry has at least two voltage supply rails, with the voltage supply rail closest to the ground potential at a second potential, the second potential being smaller than the first potential. A Radio Frequency (RF) carrier is digitally Phase Shift Keying (PSK) modulated for transmission across the isolation barrier. The unmodulated RF carrier could also be transmitted across the isolation barrier. PSK modulation could be applied to the RF carrier based on a test waveform to generate a PSK-modulated test signal for transmission while a voltage transient is applied between the high voltage circuitry and the low voltage circuitry.

Galvanically isolated amplifiers and related methods

A method for controlling local oscillator (LO) feed-through in a direct transmitter includes detecting a signal level corresponding to LO feed-through in a radio frequency (RF) signal that is output by a direct transmitter. Responsive to detecting the signal level corresponding to LO feed-through, DC offset levels are modified for an in-phase (I) signal and/or a quadrature-phase (Q) signal in the direct transmitter.

Systems and methods for controlling local oscillator feed-through

A low noise RF driver circuit including at least two series-coupled driver stages which receive a frequency modulated signal and an amplitude modulated signal that is applied to the supply voltage input of the driver stages, and provide a combined output signal. The RF driver circuit can be implemented in CMOS technology and integrated with other components of an RF communication subsystem, such as an RF transceiver circuit and power amplifier. Each driver stage includes a complementary pair of transistors with source degeneration resistors for linearity and gain control.

Low noise RF driver

According to an exemplary embodiment, a voltage controlled oscillator includes a PFET having a first gate terminal, a first source terminal, a first drain terminal, and a first body terminal, where the first source terminal is coupled to a bias voltage and the first body terminal is coupled to a first tuning voltage. The voltage controlled oscillator does not include a discrete varactor diode. The voltage controlled oscillator further includes an NFET having a second gate terminal, a second source terminal, a second drain terminal, and a second body terminal, where the second body terminal is coupled to a second tuning voltage. The first and second drain terminals drive an output of the voltage controlled oscillator, where a frequency of the output is responsive to a change in the first tuning voltage. The change in the first tuning voltage causes a change in source-to-body capacitance of the PFET.

Voltage controlled oscillator with varactor-less tuning

A current mode logic (CML) circuit includes an emitter follower circuit, a CML gate, and a Schottky diode that is coupled between the emitter follower circuit and the CML gate. Methods and other systems are also provided.

Low-voltage current mode logic circuits and methods

PLL frequency synthesizers and their calibration techniques are described. The PLL frequency synthesizers are used to generate digital modulation of a carrier signal. A digital frequency divider in the feedback path of the loop has its division ratio controlled by a digital &Dgr;-&Sgr; modulator. The modulation of the carrier is achieved by applying a modulation signal to the input of the &Dgr;-&Sgr; modulator and to the input of the voltage-controlled oscillator of the PLL. The high frequency path and low frequency path of the modulation signal must be adjusted with respect to one another in order to obtain a good modulation. As the low frequency path can be accurately set, the calibration is performed only on the high frequency path. Digital calibration techniques for the high frequency path are described.

Delta-sigma based dual-port modulation scheme and calibration techniques for similar modulation schemes

A One Bit Digital Quadrature Vector Modulator (DQVM) and a method of generating single sideband output signals are useful for a wide range of radio frequency, signal processing and wireless applications. The DQVM simplifies the necessary digital multiplication by using noise shaped one bit versions of both the baseband I and Q signals to be modulated and the I and Q modulating signals. The one bit DQVM enables a much faster digital implementation of the digital quadrature vector modulation function than can be achieved with conventional multi-bit digital techniques. In addition the single sideband upconversion of the DQVM achieves high suppression of the unwanted sideband by applying an offset to one of the low speed input samples. Digital vector modulators are an improvement over conventional analog vector modulators as they are not subject to the amplitude and phase matching problems inherent in analog vector modulators.

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Ottawa, Canada

Christian Cojocaru