Stichting Imec Nederland

Imec Vzw

Imec

Katholieke Universiteit Leuven, Ku Leuven R&d

Jiawei Xu

Refet Firat Yazicioglu

Nick Van Helleputte

Shuang Song

Pieter Harpe

Roland Van Wegberg

Filip Tavernier

Qiuyang Lin

A light-to-digital converter () comprises a light-to-current converter (); a current integrator () with an integrator output () resettable to a baseline level; and a counter () with a digital output (), wherein the light-to-current converter () is switchably connectable as a positive integration input to the current integrator (), for, during a light-collecting phase (-), integrating a current from the light-to-current converter (), the integrator output () starting from the baseline value and ending at a value to be digitized; a reference current source () is switchably connectable as a negative integration input to the current integrator (), for, during a counting phase (-) subsequent to the light-collecting phase (-), integrating a reference current from the reference current source (), the integrator output () starting from the value to be digitized and ending at the baseline value, the time spent integrating the reference current corresponding to the value to be digitized; and the counter () is configured for measuring the time.

Light-to-digital converter

A device for read-out of a photoplethysmography (PPG) signal comprises: a photodiode, which is configured to detect a PPG signal, the photodiode comprising a first and a second terminal; and a read-out circuitry for reading out the PPG signal, wherein an input stage is connected to receive a first and a second input signal from the terminals and a DC bias voltage, and wherein the input stage is configured for current sensing to provide a fully differential amplification of the input signals to a first and a second current signal, and wherein an output stage is configured to receive the current signals, wherein the current signals comprise an AC and a DC component of the PPG signal, and wherein the output stage is configured to generate a differential output voltage through a gain component.

Device for read-out of a photoplethysmography signal and a wearable sensor

The present disclosure is directed to an impedance spectroscopy system for bio-impedance measurement. The impedance spectroscopy system includes a signal generator configured to generate a signal with a broadband frequency spectrum and to generate an analog injection current from the signal with the broadband frequency spectrum. The analog injection current has a high pass frequency characteristic. The impedance spectroscopy system also includes an amplifier configured to measure a voltage signal in response to the analog injection current and to simultaneously measure a biopotential signal. Further, the impedance spectroscopy system includes a processor configured to analyze the voltage signal to derive a bio-impedance spectrum as well to derive further information from the biopotential signal.

Bio-impedance spectroscopy system and method for bio-impedance measurement

According to an aspect of the present inventive concept there is provided a reconfigurable sensor circuit comprising:

Reconfigurable sensor circuit

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 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.

Growing community of inventors

Eindhoven, Netherlands

Jiawei Xu