Inventor · disambiguated record
David R. Welland
Also filed as: WELLAND DAVID · WELLAND DAVID R
146 granted patents·11 pending applications·4,987 citations·filing 1980–2015
99Inventor score
Top patents by PatentIndex Score
157 records- 0198US6137372AMethod and apparatus for providing coarse and fine tuning control for synthesizing high-frequency signals for wireless communicationsSILICON LAB INC·Filed 1998·Granted Oct 24, 2000·180 cites·29 claims
- 0297US6323735B1Method and apparatus for synthesizing high-frequency signals utilizing on-package oscillator circuit inductorsSILICON LAB INC·Filed 2000·Granted Nov 27, 2001·149 cites·33 claims
- 0397US5870046AAnalog isolation system with digital communication across a capacitive barrierSILICON LAB INC·Filed 1997·Granted Feb 9, 1999·157 cites·11 claims
- 0497US5796535ASampled amplitude read channel employing a user data frequency synthesizer and a servo data frequency synthesizerCIRRUS LOGIC INC·Filed 1995·Granted Aug 18, 1998·137 cites·22 claims
- 0596US6741846B1Method and apparatus for operating a PLL with a phase detector/sample hold circuit for synthesizing high-frequency signals for wireless communicationsSILICON LAB INC·Filed 2000·Granted May 25, 2004·66 cites·39 claims
- 0696US6167245AMethod and apparatus for operating a PLL with a phase detector/sample hold circuit for synthesizing high-frequency signals for wireless communicationsSILICON LAB INC·Filed 1998·Granted Dec 26, 2000·111 cites·20 claims
- 0795US7092675B2Apparatus and methods for generating radio frequencies in communication circuitry using multiple control signalsSILICON LAB·Filed 2002·Granted Aug 15, 2006·84 cites·35 claims
- 0895US7003023B2Digital isolation system with ADC offset calibrationSILICON LAB INC·Filed 2003·Granted Feb 21, 2006·98 cites·16 claims
- 0995US6727754B2RF power detectorSILICON LAB INC·Filed 2001·Granted Apr 27, 2004·46 cites·47 claims
- 1095US6646822B1Sampled amplitude read channel employing pipelined reads to reduce the gap between sectorsCIRRUS LOGIC INC·Filed 1997·Granted Nov 11, 2003·99 cites·14 claims
- 1195US6150891APLL synthesizer having phase shifted control signalsSILICON LAB INC·Filed 1998·Granted Nov 21, 2000·96 cites·21 claims
- 1295US5892632ASampled amplitude read channel employing a residue number system FIR filter in an adaptive equalizer and in interpolated timing recoveryCIRRUS LOGIC INC·Filed 1996·Granted Apr 6, 1999·117 cites·16 claims
- 1394US6570513B2Isolation system with digital communication across a capacitive barrierSILICON LAB INC·Filed 2001·Granted May 27, 2003·44 cites·45 claims
- 1494US6327463B1Method and apparatus for generating a variable capacitance for synthesizing high-frequency signals for wireless communicationsSILICON LAB INC·Filed 1998·Granted Dec 4, 2001·95 cites·39 claims
- 1594US6308055B1Method and apparatus for operating a PLL for synthesizing high-frequency signals for wireless communicationsSILICON LAB INC·Filed 1998·Granted Oct 23, 2001·75 cites·35 claims
- 1694US6147567AMethod and apparatus for providing analog and digitally controlled capacitances for synthesizing high-frequency signals for wireless communicationsSILICON LAB INC·Filed 1998·Granted Nov 14, 2000·105 cites·31 claims
- 1794US5359631ATiming recovery circuit for synchronous waveform samplingCIRRUS LOGIC INC·Filed 1992·Granted Oct 25, 1994·71 cites·15 claims
- 1894US5039989ADelta-sigma analog-to-digital converter with chopper stabilization at the sampling frequencyCRYSTAL SEMICONDUCTOR CORP·Filed 1989·Granted Aug 13, 1991·88 cites·22 claims
- 1993US7050509B2Digital isolation system with hybrid circuit in ADC calibration loopSILICON LAB INC·Filed 2002·Granted May 23, 2006·76 cites·5 claims
- 2093US6760575B2Method and apparatus for generating a variable capacitance for synthesizing high-frequency signals for wireless communicationsSILICON LAB INC·Filed 2001·Granted Jul 6, 2004·43 cites·35 claims
- 2193US6549765B2Phase locked loop circuitry for synthesizing high-frequency signals and associated methodSILICON LAB INC·Filed 2001·Granted Apr 15, 2003·34 cites·35 claims
- 2293US6297755B2Analog isolation system with digital communication across a capacitive barrierSILICON LAB INC·Filed 2001·Granted Oct 2, 2001·41 cites·81 claims
- 2393US5648738ARead channel having auto-zeroing and offset compensation, and power-down between servo fieldsCIRRUS LOGIC INC·Filed 1994·Granted Jul 15, 1997·61 cites·26 claims
- 2491US6388536B1Method and apparatus for providing coarse and fine tuning control for synthesizing high-frequency signals for wireless communicationsSILICON LAB INC·Filed 2000·Granted May 14, 2002·42 cites·32 claims
- 2591US4709225ASelf-calibration method for capacitors in a monolithic integrated circuitCRYSTAL SEMICONDUCTOR CORP·Filed 1985·Granted Nov 24, 1987·73 cites·4 claims
- 2690US7471940B2Ratiometric clock systems for integrated receivers and associated methodsSILICON LAB INC·Filed 2007·Granted Dec 30, 2008·14 cites·24 claims
- 2790US7289145B2Correlated double sampling variable gain amplifier circuit for use in a digital cameraCIRRUS LOGIC INC·Filed 2006·Granted Oct 30, 2007·17 cites·12 claims
- 2890US7272373B2Ratiometric clock systems for integrated receivers and associated methodsSILICON LAB INC·Filed 2004·Granted Sep 18, 2007·34 cites·26 claims
- 2990US6917245B2Absolute power detectorSILICON LAB INC·Filed 2002·Granted Jul 12, 2005·41 cites·31 claims
- 3090US6756849B2Absolute power detectorFiled 2003·Granted Jun 29, 2004·56 cites·20 claims
- 3190US6225927B1Analog isolation system with digital communication across a capacitive barrierSILICON LAB INC·Filed 1999·Granted May 1, 2001·67 cites·49 claims
- 3290US6061009AApparatus and method for resetting delta-sigma modulator state variables using feedback impedanceSILICON LAB INC·Filed 1998·Granted May 9, 2000·78 cites·30 claims
- 3390US5134401ADelta sigma modulator having programmable gain/attenuationANALOG DEVICE INC·Filed 1991·Granted Jul 28, 1992·86 cites·32 claims
- 3489US5159341ATwo phase sampling for a delta sigma modulatorANALOG DEVICES INC·Filed 1991·Granted Oct 27, 1992·71 cites·14 claims
- 3588US7292091B1Method and apparatus for reducing interferenceSILICON LAB INC·Filed 2005·Granted Nov 6, 2007·9 cites·5 claims
- 3688US6611553B1Isolation system with digital communication across a capacitive barrierSILICON LAB INC·Filed 2000·Granted Aug 26, 2003·41 cites·60 claims
- 3788US6317006B1Frequency synthesizer utilizing phase shifted control signalsSILICON LAB INC·Filed 2000·Granted Nov 13, 2001·36 cites·41 claims
- 3887US7209011B2Method and apparatus for synthesizing high-frequency signals for wireless communicationsSILICON LAB INC·Filed 2005·Granted Apr 24, 2007·16 cites·25 claims
- 3987US6233441B1Method and apparatus for generating a discretely variable capacitance for synthesizing high-frequency signals for wireless communicationsSILICON LAB INC·Filed 1998·Granted May 15, 2001·56 cites·33 claims
- 4087US5786951ASampled amplitude read channel employing a discrete time noise generator for calibrationCIRRUS LOGIC INC·Filed 1996·Granted Jul 28, 1998·52 cites·10 claims
- 4187US5451901ATransconductance amplifiers and exponential variable gain amplifiers using the sameCIRRUS LOGIC INC·Filed 1994·Granted Sep 19, 1995·44 cites·24 claims
- 4286US6750906B1Histogram-based automatic gain control method and system for video applicationsCIRRUS LOGIC INC·Filed 1998·Granted Jun 15, 2004·81 cites·14 claims
- 4386US6226506B1Method and apparatus for eliminating floating voltage nodes within a discreetly variable capacitance used for synthesizing high-frequency signals for wireless communicationsSILICON LAB INC·Filed 1998·Granted May 1, 2001·63 cites·21 claims
- 4486US5055846AMethod for tone avoidance in delta-sigma convertersCRYSTAL SEMICONDUCTOR CORP·Filed 1990·Granted Oct 8, 1991·55 cites·12 claims
- 4585US7262725B2Digital expander for generating multiple analog control signals particularly useful for controlling an oscillatorSILICON LAB INC·Filed 2006·Granted Aug 28, 2007·12 cites·14 claims
- 4685US6993314B2Apparatus for generating multiple radio frequencies in communication circuitry and associated methodsSILICON LAB INC·Filed 2002·Granted Jan 31, 2006·35 cites·14 claims
- 4785US6683548B2Analog isolation system with digital communication across a capacitive barrierSILICON LAB INC·Filed 2003·Granted Jan 27, 2004·18 cites·55 claims
- 4885US6108151ASampled amplitude read channel for reading user data and embedded servo data from a magnetic mediumCIRRUS LOGIC INC·Filed 1997·Granted Aug 22, 2000·34 cites·8 claims
- 4984US9726696B2Precision reference circuit and related methodPOWELL MATTHEW·Filed 2012·Granted Aug 8, 2017·8 cites·20 claims
- 5084US7154940B2Isolation system with digital communication across a capacitive barrierSILICON LAB INC·Filed 2003·Granted Dec 26, 2006·27 cites·50 claims
Showing the top 50 of 157 patent records by PatentIndex Score.
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Identity basis: PatentsView inventor disambiguation (2025Q4-odp release). How scoring works →