Silicon Laboratories Inc.

Cirrus Logic Inc.

Crystal Semiconductor Corporation

Other

St-ericsson Sa

Black Sand Technologies, Inc.

Silacon Laboratories Inc.

David R Welland

Jeffrey William Scott

Navdeep S Sooch

Caiyi Wang

Timothy Joseph Dupuis

Donald A Kerth

Andrew W Krone

George Tyson Tuttle

Richard T Behrens

Jerrell P Hein

Trent O Dudley

Nadi Rafik Itani

Susanne A Paul

Ali M Niknejad

William G Bliss

G Tyson Tuttle

Christopher P Zook

Neal Glover

David E Reed

Douglas R Holberg

Paul M Romano

John Blake Pavelka

Lysander Lim

Tyson Tuttle

Edmund G Healy

Diwakar Vishakhadatta

Jerrel P Hein

Bruno Werner Garlepp

Vishnu Shankar Srinivasan

Yunteng Huang

G Diwakar Vishakhadatta

Vadim A Konradi

Scott Willingham

Sandra Marie Johnson

Michael Sean Franklin

Parker Dorris

Bruce Philip Del Signore

Michael James Callahan, Jr

Matthew Powell

Ramkishore Ganti

Mark S Spurbeck

Brannon Craig Harris

Alan Wayne Hansford

Syed Khalid Azim

Ash Prabala

Shih-chung Chao

Richard T Behems

Jeffery W Scott

William G Gliss

Iuri Mehr

Bradley J Fluke

A method includes alternately coupling a selected one of a plurality of current sources and two or more of the plurality of current sources to a first terminal of a bipolar device during first and second phases of a modulator cycle of a plurality of modulator cycles. The method further includes providing sampled voltages from the first terminal of the bipolar device to a modulator to produce a modulator output signal, filtering the modulator output signal to produce a filtered output signal using a back-end filter having an impulse response, and determining a temperature in response to the filtered output signal.

Temperature Measurement Circuitry and Method

A controller for a capacitive touch screen or the like includes a touch resolve subsystem and a processor. The touch resolve subsystem, when activated, measures a plurality of capacitance values using a plurality of input pins. The processor uses the plurality of capacitance values at each of a plurality of values of a parameter to create an interference map.

Controller and method for controlling a capacitive touch screen or the like

A controller for a capacitive touch screen includes a touch resolve subsystem and a processor. The touch resolve subsystem, in response to a trigger input, measures a plurality of capacitance values using a plurality of input pins. The processor controls the touch resolve subsystem to acquire a baseline capacitance in a calibration mode, to acquire a frame comprising the plurality of capacitance values in a normal operation mode, and to update the baseline capacitance to a new baseline capacitance in the normal operation mode in response to the frame without entering the calibration mode.

In one form, a reference circuit includes a measurement circuit and a determination circuit. The measurement circuit has an output for providing a ratio of a difference in base-to-emitter voltage (V) of a bipolar device at different current densities to a Vof the bipolar device at a first current density. The determination circuit has an input coupled to the measurement circuit, and an output for providing a digital value of a parameter in response to the ratio. In another form, the reference circuit further includes a voltage generation circuit having an input coupled to the determination circuit, and an output, for modulating an analog voltage using the digital value to provide a reference voltage to the output, wherein the reference voltage is temperature compensated over a temperature range.

Precision reference circuit and related method

Temperature measurement circuitry and system

A method and apparatus is provided for reducing interference in circuits. A management strategy is provided to reduce reference spurs and interference in circuits. The management strategy uses a combination of one or more techniques which reduce the digital current, minimize mutual inductance, utilize field cancellation, prevent leakage current, and/or manage impedance. These techniques may be used alone, or preferably, used on combination with one another.

Method and apparatus for reducing interference

A circuit for determining a value of a variable capacitor includes first circuitry for generating a first indication when a variable voltage across the variable capacitor exceeds a threshold voltage. Second circuitry generates a second indication when a reference voltage across a reference capacitor exceeds the threshold voltage. Control logic responsive to the first and second indications generate a control signal indicating whether the first indication or the second indication occurs first. A successive approximation engine generates an N-bit control value responsive to the control signal. A variable current source is responsive to the N-bit control value for generating a variable current to the first circuitry. A reference current source generates a reference current to the second circuitry.

System and method for determining capacitance value

An RF transmitter () includes a shared local oscillator circuit (), transmit path circuitry (), a divider (), and a lowpass filter (). The shared local oscillator circuit () generates a shared LO signal (). The transmit path circuitry () mixes a baseband signal () and an IF mixing signal () to provide an IF signal (), and converts the IF signal () to an RF transmit signal () at a desired frequency using an RF mixing signal received at a mixing input thereof. The divider () divides the shared LO signal () to provide an unfiltered RF mixing signal. The lowpass filter () has an input for receiving the unfiltered RF mixing signal, and an output coupled to the mixing input of the transmit path circuitry () for providing the RF mixing signal.

Local oscillator (LO) port linearization for communication system with ratiometric transmit path architecture

A method and apparatus is provided for detecting the output power of a power amplifier. The output power is detected by detecting the absolute values of the voltage and current at the output of the amplifier and mixing the detected voltage and current to generate a signal related to the output power.

Absolute power detector

Growing community of inventors

Austin, TX, United States of America

David R Welland