Analog Devices,inc.

Other

Panasonic Intellectual Property Management Co., Ltd.

Evgueni Vladimirovich Ivanov

Javier Alejandro Salcedo

David Frank Bolognia

Arthur Joseph Kalb

Vikram Venkatadri

Alain Valentin Guery

J Brian Harrington

Carlos Calvo

Hari Chauhan

According to one example configuration, an apparatus enhances functionality of a mobile communication device. The apparatus includes an encasement in which to retain the mobile communication device and supplemental circuitry. The supplemental circuitry is operable to: i) control an optical transmitter in the supplemental circuitry to irradiate matter under test, ii) monitor attributes of an optical signal reflected off the matter under test and received by the optical receiver; and iii) communicate the attributes of the optical signal from the supplemental circuitry to the mobile communication device over a communication link. The supplemental circuitry optionally includes multiple electrodes to further monitor attributes of the matter under test.

Smartphone companion device material sensing and improved phone performance

Embodiments of the present invention provide systems and methods for compact birefringent interferometer and Fourier Transform spectrometer which uses rotating birefringent crystal plate to produce variable optical path difference (OPD) between ordinary and extraordinary rays of the incident light travelling through the birefringent crystal plate. In one aspect, the system includes an optical birefringent interferometer and Fourier Transform spectrometer comprising a polarizing beamsplitter, a reflective mirror, a rotating and a fixed compensating birefringent plate. In another aspect, the interferometer and Fourier Transform spectrometer may further include a photodetector in order to obtain a spectrum of the incoming radiation. In yet another aspect, the interferometer and Fourier Transform spectrometer may further include a one-dimensional or two-dimensional photodetector array or in order to obtain a hyper-spectral image of the radiation source or illuminated object.

Birefringent interferometer and fourier transform spectrometer

The present disclosure provides bandgap reference circuits having multi-level chopping actions to current mirror circuits for the purpose of reducing the flicker noise of the output reference voltage. A bandgap reference circuit includes a first current mirror including a pair of a first MOSFET and a second MOSFET, a second current mirror comprising a third MOSFET electrically connected to the first current mirror, and configured to provide a reference voltage at a drain, a first bipolar junction transistor electrically connected to the first current mirror, a second bipolar junction transistor connected to the first current mirror via a first resistor, a third bipolar junction transistor connected to the third MOSFET via a second resistor. The bandgap reference circuit further includes an operational amplifier to control the MOSFETs and a plurality of chopping switches configured to perform chopping actions on outputs of the first current mirror and the second current mirror.

Bandgap reference circuit with reduced flicker noise

Apparatus and methods for overvoltage switches with active leakage current compensation are provided. In certain configurations, an IC includes an input node and a protection device or overvoltage switch electrically connected to the input node. The protection device includes a first well and a second well. The second well is positioned adjacent to the first well and has a conductivity type opposite that of the first well. Additionally, a first terminal of the protection device is electrically connected to the first well and to the input node of the IC. The protection device further includes a leakage current compensation circuit that is used to control a voltage level of the second well based on a voltage level of the first terminal to inhibit a leakage current of the first terminal of the protection device.

Apparatus and methods for overvoltage switches with active leakage current compensation

Apparatus and methods for digitally-assisted feedback offset correction are provided herein. In certain configurations, an amplifier includes amplification circuitry for providing amplification to an input signal and chopping circuitry for compensating for an input offset voltage of the amplifier. Additionally, the amplifier further includes a digitally-assisted feedback offset correction circuit, which includes a chopping ripple detection circuit, a feedback-path chopping circuit, a digital correction control circuit, and an offset correction circuit. The chopping ripple detection circuit generates a detected ripple signal based on detecting an output ripple of the amplifier. Additionally, the feedback-path chopping circuit demodulates the detected ripple signal using the amplifier's chopping clock signal. The digital correction control circuit receives the demodulated ripple signal, which the digital correction control circuit uses to control a value of a digital offset control signal that controls an amount of input offset correction provided by the offset correction circuit.

Apparatus and methods for chopping ripple reduction in amplifiers

A circuit operating with a switching clock signal and a sampling clock signal can have one or more of its switching and sampling clock signals periodically phase-reversed. The period of phase reversal can be greater than twice the period of the original switching and/or sampling clock signal, and in certain configurations the switching and sampling clock signals can be synchronized. With a selection of phase reversal period (or frequency), aliasing frequency components of the mixed signal from the switching and sampling clock signals can be removed.

Apparatus and methods for anti-aliasing in electronic circuits

Apparatus and methods for adaptive level shifting are provided. In one embodiment, a method of level shifting in an adaptive level shifter (ALS) is provided. The technique includes charging a first capacitor and a second capacitor each to a voltage that is about equal to a difference between a common mode voltage of a differential input voltage signal and a reference voltage. The technique can further include inserting the first capacitor between a first input and a first output of the ALS and the second capacitor between the second input and a second output of the ALS. The technique can further include switching the first capacitor and the second capacitor such that the first capacitor is inserted between the second input and the second output and the second capacitor is inserted between the first input and the first output.

Apparatus and methods for adaptive common-mode level shifting

Apparatus and methods for electronic amplification are provided. In one embodiment, an amplifier includes a first adaptive level shifter (ALS), a second ALS, a first transconductance amplification circuit, a second transconductance amplification circuit, and a transimpedance amplification circuit. The first ALS and the second ALS are electrically coupled to the first and second transconductance amplification circuits to improve the input voltage range and common-mode rejection ratio (CMRR) of the amplifier. The transimpedance amplification block is electrically coupled to the first and second transconductance amplification blocks and generates an output voltage of the amplifier. The first ALS receives a differential input voltage, and the second ALS is configured to receive a feedback signal configured to change in relation to the output voltage signal.

Apparatus and methods for electronic amplification

An amplifier circuit includes a first amplifier stage having a first output node; a second amplifier stage having a second output node; and a compensation block electrically coupled between the first and second output nodes. The compensation block has a compensation capacitor electrically coupled to the first node and electrically connectable to the second node, and has an impedance electrically connectable to the compensation capacitor. The compensation capacitor is electrically coupled via a switch to the impedance such that the compensation capacitor can contribute a zero to shunt branch formed by the compensation capacitor and impedance when the compensation capacitor is disconnected from the second node.

Apparatus and method for miller compensation for multi-stage amplifier

Apparatus and methods for biasing amplifiers are provided. In certain implementations, a bias circuit is provided for controlling the drain-source voltage of input transistors electrically connected to the inputs of a transconductance amplification circuit. For example, the bias circuit can maintain a relatively constant drain-source voltage in the input transistors by using a feedback loop that includes a feedback amplifier for adjusting the bias current of the input transistors based upon a difference between the drain and source voltages of the input transistors. In certain implementations, the feedback amplifier has an offset voltage equal to about the desired value of the drain-source voltage, and the feedback amplifier is configured to adjust the bias current until the difference between the inputs of the feedback amplifier is equal to about the offset voltage.

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Lexington, MA, United States of America

Evgueni Vladimirovich Ivanov