Imec

Imec Vzw

Katholieke Universiteit Leuven, Ku Leuven R&d

Stichting Imec Nederland

Katholieke Universiteit Leuven

Refet Firat Yazicioglu

Sunyoung Kim

Nick Van Helleputte

Jiawei Xu

Patrick Merken

Hyejung Kim

Tom Torfs

Julien Penders

Srinjoy Mitra

Bogdan Raducanu

Sachin Shrestha

Devices and systems described herein relate to a sensing device that includes an output area and an electrode area. The output area includes an output circuit comprising an integrator adapted to integrate a received current so as to generate an output voltage corresponding to the received current. The electrode area includes an electrode comprising an exposed, electrically conductive, surface area and electrode circuitry connected to the exposed surface area. The electrode circuitry comprises a voltage-to-current transducer adapted to produce a wire current corresponding to a voltage present at the exposed surface area. The sensing device also includes a connecting wire electrically connecting the electrode circuitry to the output circuit, wherein the current received by the output circuit is the wire current.

Sensing device with array of microelectrodes

A biopotential signal acquisition system, comprising: a first active electrode including an integrated pre-amplifier and an analogue to digital converter; a second active electrode including an integrated pre-amplifier and an analogue to digital converter, wherein the second active electrode has variable gain; a test signal generator for generating a test signal at a test frequency and coupling the test signal to the first and/or second active electrodes; and a digital signal processor configured to: process the digital outputs of the first and second active electrodes to derive a gain control signal based on a difference between the first and second active electrode outputs at the test frequency, and apply the gain control signal to the second active electrode. The disclosure also relates to an electronic circuit or device and a biopotential signal acquisition method.

Biopotential signal acquisition system and method

A current generator is disclosed. An example current generator includes a plurality of current cells connected in parallel, each current cell being connected to a switch. The current generator further includes a first summer configured to sum the output of each current cell of a first subset of the plurality of current cells and a second summer configured to sum the output of each current cell of a second subset of the plurality of current cells. The current generator also includes a combiner configured to combine the outputs of the first and second summers. Further, each switch is switchable according to a sequence to generate a summed output of the current cells at a plurality of quantization levels to generate positive and/or negative alternations of a pseudo-sinusoidal, alternating current.

Current generator

A biopotential signal acquisition system including an analog readout unit configured to receive an analog biopotential signal, which may be acquired from at least one electrode attached to a body; and to extract an analog measured biopotential signal and an analog reference signal. The system also includes an ADC unit configured to provide a digital version of the analog measured biopotential signal and the analog reference signal, a digital filter unit configured to calculate a digital motion artifact estimate based on the digital version of the measured biopotential signal and the reference signal. The system further comprises a reference signal processing unit configured to convert the reference signal into a new reference signal being provided to the digital filter unit based on the correlation between the measured biopotential signal and the reference signal.

System and method for acquisition of biopotential signals with motion artifact reduction

A biopotential signal acquisition system comprising an analog readout unit configured to receive an analog biopotential signal and to extract an analog measured biopotential signal and an analog reference signal, and an ADC unit configured to provide a digital version of the analog measured biopotential signal and the analog reference signal. The system also includes a first digital filter unit comprising a cascaded integrator-comb filter configured to provide a first digital filtered version of the digital measured biopotential signal and the reference signal, and a second digital filter unit configured to calculate a digital motion artifact estimate based on the first digital filtered version signals.

System and method for acquisition of biopotential signals with motion artifact reduction in real time operation

An instrumentation amplifier includes a first amplifier having one input connected to a first input of the instrumentation amplifier, a second amplifier having one input connected to a second input of the instrumentation amplifier, and a feedback network. The feedback network including an active filter having a first low pass filter characteristic with a first cut-off frequency in respect of differential mode signals at the first and second inputs of the instrumentation amplifier, and a second low pass filter characteristic with a second cut-off frequency in respect of common mode signals at the first and second inputs of the instrumentation amplifier. The disclosure also relates to a device for acquiring biopotential signals and a signal amplification method.

Instrumentation amplifier and signal amplification method

A multi-channel biopotential signal acquisition system is disclosed. In the system, a plurality of biopotential channels is corrected for common-mode interference. In one aspect, each biopotential channel includes an electrode for providing a biopotential input signal and an associated amplifier for amplifying the biopotential input signal and providing a biopotential output signal. The output signal is processed in a processor. Each biopotential output signal is passed to a common-mode feedback system, which determines an average common-mode signal and feeds that signal back to each of the amplifiers in each of the biopotential channels to enhance common-mode rejection ratio of the system.

Multi-channel biopotential signal acquisition systems

A system for the analysis of ECG signals is disclosed. The system may comprise (i) at least one readout channel, configured to receive an analog ECG signal acquired from at least one electrode attached to a body, and to extract an analog measured ECG signal and analog electrode-skin impedance signals; (ii) at least one ADC, configured to convert those extracted analog signals at the readout channel into digital signals; (iii) a digital adaptive filter unit, configured to calculate a digital motion artifact estimate based on said digital versions of the measured ECG signal and the electrode-skin impedance signals; (iv) at least one DAC, configured to convert said digital motion artifact estimate into an analog signal; and (v) a feedback loop for sending said analog motion artifact estimate signal back to the readout channel configured to deduct said analog motion artifact estimate signal from said analog measured ECG signal.

Biomedical acquisition system with motion artifact reduction

A microprocessor configured to receive and process digitized signals derived from an analogue ECG signal is provided. An example microprocessor comprises a beat detection unit configured to receive the in-phase and quadrature phase band power signals, calculate a band power value and an adaptive threshold value, and compare said band power value with said adaptive threshold value to detect a QRS complex of the ECG signal indicative of a detected valid beat; and an R peak detection unit configured to receive the digital ECG signal and information about the detected valid beat, select a portion of the received ECG signal as a first time window around the detected valid beat; determine the location of a first R peak position; and perform a time domain search in a second time window around said first R peak position in order to refine the location of an R peak position.

System and method for the analysis of electrocardiogram signals

An analog signal processor (ASP) application-specific integrated circuit (ASIC) is disclosed. The ACIS can be used for remotely monitoring ECG signals of a subject that has reduced power consumption. In one aspect, the ASIC performs the functions of: ECG signal extraction with high resolution using ECG readout channel, feature extraction using a band-power extraction channel, adaptive sampling the ECG signals using an adaptive sampling analog-to-digital converter, and impedance monitoring for signal integrity using an impedance monitoring channel. These functions enable the development of wireless ECG monitoring systems that have significantly lower power consumption but are more efficient that predecessor systems. In one embodiment, the ASP ASIC consumes 30 &#x3bc;W from a 2V supply with compression provided by adaptive sampling providing large reductions in power consumption of a wireless ECG monitoring system of which the ASP ASIC forms a part.

Analogue signal processors

A method and apparatus is disclosed for adaptively sampling an analogue signal to increase the sampling rate in the presence of high frequency content within the signal, for example, QRS complex of an ECG signal. In one aspect, a change in a derivative of the analogue signal is used to control a voltage-controlled oscillator to provide a clock signal for an analogue-to-digital converter. The change in the derivative is compared to an automatically controlled threshold value. The clock signal controls the sampling rate of the analogue-to-digital converter so that the sampling rate is increased from one level, where only P and T waves are present to another higher level when the QRS complex has been detected.

Adaptive sampling

The present invention relates to a large time constant steering circuit for slowly changing a voltage on a node between at least two discrete voltage levels. The present invention further relates to a slow steering current DAC comprising said large time constant steering circuit. The present invention further relates to an instrumentation amplifier device comprising a current balancing instrumentation amplifier for amplifying an input signal to an amplified output signal and a DC servo-loop for removing a DC-component from the input signal. The present invention further relates to an EEG acquisition ASIC comprising said instrumentation amplifier device.

Large time constant steering circuit and instrumentation amplifier implementing same

A method and device is disclosed for continuously and simultaneously measuring an impedance signal and a biopotential signal on a biological subject's skin. In one aspect, the method includes attaching input and output electrodes to the biological subject's skin and applying a predetermined alternating current having a first frequency to the output electrodes for creating an alternating voltage signal over the input electrodes. The first frequency is above a predetermined minimum frequency. The method also includes measuring an input signal from the input electrodes which includes a biopotential signal and the alternating voltage signal. The method also includes extracting from the input signal the biopotential signal and the alternating voltage signal, and determining the impedance signal from the alternating voltage signal. The alternating voltage signal is extracted by amplifying and demodulating the input signal using a control signal having a frequency equal to the first frequency.

Growing community of inventors

Leuven, Belgium

Refet Firat Yazicioglu