Analog Devices,inc.

Precision Monolithics, Inc.

Other

Rocktron Corporation

Derek F Bowers

Michael Thomas Dunbar

Bernard Patrick Stenson

William Allan Lane

Paul Malachy Daly

Andrew David Bain

Anne Maria Deignan

Patrick Martin McGuinness

James K Waller, Jr

Douglas S Smith

James J Ashe

Craig Wilson

Eric Modica

Gregory Keith Cestra

Larry C Tippie

Patrick Martin McGuiness

Azita Ashe

Edward John Coyne

Zoltan Zansky

Moshe Gerstenhaber

Ali Tasdighi

Chau Cuong Tran

Joseph C Buxton

Steven M Pietkiewicz

Peter S Henry

Thomas S Szepesi

Lewis W Counts

Michael Lee

Mohammad S Nasser

Oljeta Bida Qirko

Steven Wright

Philip Judge

Leo P Mchugh

Stephen D Parks

James G Staley

Charles R Wicker

Pak W Kung

Azita Soroushian-Ashe

Walter Heinzer

Saurabh M Desai

An amplifier includes a bootstrap circuit for improving a linearity of the amplifier and a feed-forward circuit for modifying a voltage of the bootstrap circuit in response to a change in an input signal. Modifying the voltage using the feed-forward circuit prevents a phase-inversion condition of the amplifier.

Feed-forward circuit to prevent phase inversion

Amplifiers with voltage and current feedback error correction are provided. In one embodiment, an amplifier includes a first input terminal, a second input terminal, an output terminal, a first stage, and a voltage feedback amplification circuit. The first stage can be used to generate first and second output currents, which can be used to control a voltage level of the output terminal. The first and second output currents can change in response to a current feedback signal and a differential input signal received between the first and second input terminals. The first stage can also generate a voltage feedback signal, which can be used by the voltage feedback amplification circuit to control a voltage level of the second input terminal based on a voltage level of the first input terminal.

Amplifier with voltage and current feedback error correction

A circuit for providing a DC output equal to the RMS value of a time-varying input signal, the circuit including: (i) an RMS-to-DC converter for producing the DC output and (ii) a high-order low-pass filter comprising at least first and second low-pass filters connected in series to cooperatively reduce at least one of ripple in the DC output, ripple in an denominator feedback loop, or DC error in the DC output.

Dynamic improvement in RMS to DC converters

A junction field effect transistor having a drain and a source, each defined by regions of a first type of semiconductor interconnected by a channel, and in which a dopant profile at a side of the drain facing the channel is modified so as to provide a region of reduced doping compared to a body region of the drain. The region of reduced doping and the body region can be defined by the same mask and doping step, but the mask is shaped to provide a lesser amount and thus less depth of doping for the region of reduced doping.

Junction field effect transistor with region of reduced doping

Apparatus and methods are disclosed, such as those involving a junction field effect transistor for voltage protection. One such apparatus includes a protection circuit including an input, an output, and a JFET. The JFET has a source electrically coupled to the input, and a drain electrically coupled to the output, wherein the JFET has a pinch-off voltage (Vp) of greater than 2 V in magnitude. The apparatus further includes an internal circuit having an input configured to receive a signal from the output of the protection circuit. The protection circuit provides protection over the internal circuit from overvoltage and/or undervoltage conditions while having a reduced size compared to a JFET having a Vp of smaller than 2 V in magnitude.

Junction field effect transistor for voltage protection

A field effect transistor having a drain, a gate and a source, where the drain and source are formed by semiconductor regions of a first type, and in which a further doped region is provided intermediate the gate and the drain. Field gradients around the drain are thereby reduced.

Junction field effect transistor

A bipolar transistor comprising an emitter region, a base region and a collector region, and a guard region spaced from and surrounding the base. The guard region can be formed in the same steps that form the base, and can serve to spread out the depletion layer in operation.

Bipolar transistor with guard region

Bipolar transistor

A bipolar transistor, comprising a collector, a base and an emitter, in which the collector comprises a relatively heavily doped region, and a relatively lightly doped region adjacent the base, and in which the relatively heavily doped region is substantially omitted from an intrinsic region of the transistor.

Methods of forming a bipolar transistor

An input bias current cancellation circuit includes reference transistors placed in series and a current summation network. The current summation network can be configured to sum the base currents of the reference transistors to produce a summed current. A current mirror can be provided to attenuate the summed current to produce input bias cancellation currents. The input bias cancellation currents can be provided to the base inputs of an input bipolar differential pair, thereby reducing input current noise.

Apparatus and method for reducing current noise

To compensate for changes in temperature, a pair of bipolar transistors is connected to a voltage divider and receives a differential voltage that varies with temperature. The voltage divider includes a set of resistors placed in parallel. The set of resistors has a resistance that changes with temperature. As the resistance changes with temperature, the differential voltage provided by the voltage divider changes in proportion to a change in thermal voltage.

Thermal compensation of an exponential pair

In an output stage of an operational amplifier, first and second transistors each provide a collector current under quiescent conditions to first and second current sources. A resistor receives a portion of one the collector currents and produces a resistor voltage in response. An output transistor provides a quiescent current having a value calculated as a function of the resistor voltage and a base-emitter voltage of the second transistor.

Setting the DC operating current of a rail-to-rail output stage of an op-amp

A thin film composition is made from silicon, an insulator such as alumina or silicon dioxide, and at least one additional material such as chromium, nickel, boron and/or carbon. These materials are combined to provide a thin film having a &#x3c1; of at least 0.02 &#x3a9;-cm (typically 0.02-1.0 &#x3a9;-cm), and a TCR of less than &#xb1;1000 ppm/&#xb0; C. (typically less than &#xb1;300 ppm/&#xb0; C.). A sheet resistance of at least 20 k&#x3a9;/&#x25a1; may also be obtained. The resulting thin film is preferably at least 200thick, to reduce surface scattering conduction currents.

High resistivity thin film composition and fabrication method

Growing community of inventors

Sunnyvale, CA, United States of America

Derek F Bowers