Abstract: The invention concerns a conditioning circuit (10) for an external signal (IN) representative of a physiological quantity, arranged between an optical sensor (11) and a processing unit (12), the received external signal (IN) being broken down into a useful component and an ambient component, characterized in that the conditioning circuit includes a first stage (13) including a transimpedance amplifier with an incorporated high pass filter (15) using a feedback loop to subtract the ambient signal component from the received external signal, and to deliver at output an amplified useful signal (IN1), a second stage (16) including a blocker sampler circuit (17) for demodulating the amplified useful signal and delivering at output a demodulated useful signal (IN2), and a third stage (18) including a bandpass filter (19) for filtering the demodulated useful signal in the frequency band of the physiological quantity to be detected and for transmitting a conditioned signal (OUT) to the processing unit.

Abstract: A two-wire communication protocol between a controller device and a controlled device, wherein both devices are coupled by a clock line and a data line. The controller device sends control signals comprising N bits, N being greater than or equal to two, to the controlled device via the data line. Each bit of said control signals is latched onto the controlled device on consecutive edges of a clock signal sent by the controller device to the controlled device on the clock line.

Abstract: The secure integrated circuit (1) further includes storage means (2) in which confidential data is stored, such as an encryption programme and at least an encryption key, and a microprocessor unit (3) for executing the encryption programme. Said circuit further includes an oscillator stage (4, 5) supplying clock signals (CLK) in particular for clocking the sequence of operations in the microprocessor unit (3), and a random number generator (6) connected to the microprocessor unit. A random number (RNGosc) generated by the random number generator is supplied to the input of the oscillator stage to configure it such that the frequency of the clock signals supplied by the oscillator stage depends on said random number. The oscillator stage includes an RC type oscillator, in which a certain number of resistors and/or capacitors can be selected by the random number introduced at the input of the oscillator stage.

Abstract: There is described a method for waking up an optical sensing device from a sleep mode to a motion detection mode, the optical motion sensing device comprising a light source, a photodetector device, a motion sensing unit and a control unit, the motion detection mode being defined as a mode during which motion is detected between the optical motion sensing device and a portion of a surface illuminated by the light source at a defined flash rate being set between minimum and maximum flash rate values, the motion sensing unit sending motion reports to the control unit, the sleep mode being defined as a mode during which the flash rate is set to a low flash rate value being lower than the minimum flash rate value and no motion report being reported from the sensing unit to the control unit, wherein the method comprises during the sleep mode the steps of (i) illuminating said surface portion with radiation by means of the light source at the low flash rate value; (ii) detecting a radiation pattern reflected from t

Abstract: The present invention concerns a device for detecting crossing of a horizontal land demarcation marker of a carriageway for motor vehicles, characterized in that it includes at least one box (2) to be placed under the vehicle and enclosing means for projecting two light beams (4, 6) onto the carriageway (8) in two distinct zones (10, 12) that do not overlap, and distinct means for picking up each of the two light beams (14, 16) after reflection onto the carriageway (8).

Abstract: The photodiode cell (1) includes at least one photosensitive area (3), made in a silicon semiconductor substrate (2), for receiving light, particularly coherent light, and a passivation layer and a dielectric layer (4). The passivation layer is composed of at least a first silicon oxide layer (5) and a second nitride layer (6), made on the photosensitive area. The second nitride layer is made with a thickness within a determined margin, so as to be situated in a zone with the most constant possible light reflectivity independently of the thickness of the first layer. An etch (7) can be performed on one portion of the dielectric layer (4) or on the first layer (5) corresponding to half of the reception surface of the photosensitive area in order to obtain a reflectivity percentage mean of the light to be sensed by the photodiode cell.

Abstract: The present invention concerns a method and a device (30) for controlling a multiplexed display comprising a plurality of pixels arranged in lines and in columns and coupled to line electrodes and column electrodes, each of the pixels being selectively activated or deactivated by a determined combination of a line signal (BP1 to BP24) and of a column signal (FP1 to FP5) applied respectively across the corresponding line and column electrodes. According to the present invention, the display is switched between a first so-called normal operating mode, wherein all the display lines are activated, and at least a second so-called standby operating mode, wherein so-called non-active lines of the display are deactivated by applying, across the corresponding line electrodes, so-called non-activation line signals.

Abstract: There is described a method of operating an optical motion sensing device comprising a light source and a photodetector device, the method comprising the steps of a) illuminating a surface portion with radiation by means of the light source, b) detecting radiation reflected from the illuminated surface portion by means of the photodetector device, c) detecting and measuring displacement with respect to the illuminated surface portion; and d) outputting motion reports that are each representative of a magnitude of the detected displacement, steps a) to d) defining a flash period and being repeated at a selected flash rate. The method further comprises the steps of e) comparing the magnitude of the detected displacement with a determined displacement threshold, and f) increasing or decreasing the flash rate if the magnitude of the detected displacement is respectively greater or lower than the displacement threshold. There is also described an optical motion sensing device implementing this method.

Abstract: There is described a method of post-processing and reporting detected displacement in an optical pointing device as well as a sensing device for an optical pointing device implementing this method. Displacement is detected and a first count representative of a magnitude of the detected displacement is accumulated in an associated accumulation unit, this first count representing the magnitude of the detected displacement at a first resolution (or detection resolution). The first count accumulated in the accumulation unit is processed to convert this first count into a report count representing the magnitude of the detected displacement at a second resolution (or reporting resolution) lower than the first resolution. This report count is then reported, for instance to a PC or an external controller. These operations are repeated to generate periodic motion reports at the second resolution.

Abstract: There is described a method for adjusting the detection, transmission and/or reception parameters (DET, GTx, GRx) of a radiofrequency reader (10) of an electronic radiofrequency identification system as a function of the ambient electromagnetic noise. This method includes at least one step of measuring, via the radiofrequency reader, the ambient electromagnetic noise level, and a step of adjusting the detection, transmission and/or reception parameters of the radiofrequency reader on the basis of the measured ambient electromagnetic noise level. Preferably, this method further includes a step of measuring the response of a reference transponder (30) placed at least temporarily in the interrogation field of the antenna (20) associated with the radiofrequency reader, this reference transponder (30) having similar characteristics to the characteristics of the transponders to be identified.

Abstract: The invention concerns a method for filtering signals (Vin) generated by a piezo-electric type accelerometer in response to detection of a shock applied to an object to which the accelerometer is connected, this method characterised in that it ensures, during a particular step, that the signal (Vin) generated by the accelerometer, after having increased and exceeded a first threshold value (VTH,ON) decreases and becomes lower than a second threshold value (VTH,OFF) lower than the first threshold value (VTH,ON) after a period of time (TP,ON) greater than a minimum period of time (TP,ON,MIN) and less than a maximum period of time (TP,ON,MAX). The invention also concerns a device for filtering signals generated by an accelerometer in response to detection of a shock applied to an object connected to the accelerometer. Finally, the invention concerns a portable object such as a wristwatch including a detection device of this kind.

Abstract: There is described a method as well as a device for motion detect ion in an optical sensing device, such as an optical mouse. A photodetector array comprising a plurality of pixels is used to detect successive light intensity patterns of an illuminated portion of a surface with respect to which a measurement of relative motion is to be determined. Light intensity between neighbouring pixels is compared in order to determine edge direction data descriptive of light intensity differences between the pixels, such data including (i) a first edge condition, or positive edge, defined as a condition wherein light intensity of a first pixel is less than light intensity of a second pixel, and (ii) a second edge condition, or negative edge, defined as a condition wherein light intensity of the first pixel is greater than light intensity of the second pixel.

Abstract: The present invention concerns a data updating method for a non-volatile memory broken down into a plurality of similar memory subdivisions that can be erased independently of each other and among which at least two memory subdivisions (SRA, SRB) are reserved for updating data contained in each of said subdivisions (SM). The method implemented enables the execution time of an update to be reduced by simultaneously erasing the non-reserved memory subdivision (SM) to be updated and an unused reserved memory subdivision (SRB).

Abstract: The invention concerns a method for identifying a plurality of passive transponders 6 using a reader comprising several antennae whose detection fields do not merge spatially and/or temporally, said transponders comprising an analogue 34 or digital 52 memory for storing binary information for a certain time interval in the absence of any reader feeding fields. For each antenna, the method sequentially implements an anti-collision protocol during which each identified transponder is set in a “silent” mode. The method provides for this information to be stored in said memory of each transponder for a time interval including at least the switching period between a first antenna and a second antenna of the reader. This prevents detection of the same transponders by several antennae, which makes the identification method quicker and more efficient.

Abstract: There is described a method for measuring relative motion between an illuminated portion of a surface and an optical sensing device comprising a photodetector array including a plurality of rows and columns of pixels respectively aligned along first and second axes comprising essentially the steps of comparing at a first point in time light intensity between neighbouring pixels of the photodetector array and determining along each of the first and second axes, edge direction data from the detected first light intensity pattern, extracting edge inflection data from the edge direction data from the detected first light intensity pattern, comparing at a second point in time light intensity between neighbouring pixels and determining along each of said first and second axes, the edge direction data from the detected second light intensity pattern, extracting edge inflection data from the edge direction data from the detected second light intensity pattern.

Abstract: The UHF transponder includes protection against electrostatic discharge (ESD) formed by the modulation transistor (T1) and additional control means (20) for said transistor which fulfills two functions: its first response signal modulation function and an additional ESD protection function.

Abstract: A high voltage generator (GHT) incorporated in an integrated circuit (IC) and comprising a charge pump (1) whose input voltage is the supply voltage (VDD) of the integrated circuit (IC) and which is clocked by direct clock signals (?) and complemented clock signals ({overscore (?)}), characterized in that it comprises means (5) for re-injecting a fraction (VIN) of the voltage from said charge pump (VHV) into the input (6) to which said supply voltage (VDD) is applied.

Abstract: The passive transponder comprises an antenna (2) connected to an integrated circuit (6) the analogue part of which includes a passive voltage rectifier (8) supplying a rectified voltage (VDC1) and an active multiplier or booster (16) for said rectified voltage which is formed by a capacitor (C2) switched to a relatively low frequency, for example 1 MHz, by means of switches formed by transistors (18 to 21) controlled using an oscillator (24).

Abstract: There is disclosed an inverter oscillator circuit delivering an alternating output signal and including a parallel arrangement, between an input terminal and output terminal, of an inverter amplifier means, a resonator, and a resistor, first and second load capacitors being respectively connected between said input and output terminals, on the one hand, and a supply potential, on the other hand. Control means for controlling the inverter amplifier means such that it has a so called start-up transconductance value during a start-up phase and a so-called reduced transconductance value, lower than said start-up transconductance value, in steady state at the end of said start-up phase. Means for smoothing an amplitude decrease in the output signal resulting from the passage of said start-up transconductance value to said reduced transconductance value is included.

Abstract: There is disclosed a system for detecting the passage of persons or objects through an entry-exit (4) to a delimited space (2), including (i) a detection device including transmission means (8) for transmitting different first and second electromagnetic signals (a, b) in respectively first and second communication regions (A, B) spatially separated from each other and partially overlapping, (ii) portable electronic units (40) intended to be fitted to said persons or objects and including reception means for said first and second electromagnetic signals, and (iii) means for detecting the direction of passage, through said entry-exit, of a person or an object fitted with a portable electronic unit.