Abstract:
An isolated circuit of low-voltage supply of a control circuit of a high-voltage load, in or upstream of a fullwave three-phase rectifying bridge, comprising a first low-voltage capacitor having a first electrode connected to one of the rectified output terminals of the bridge, and at least one second capacitor providing said low voltage, a first electrode of the second capacitor being connected to one of the A.C. input terminals of the bridge, the respective second electrodes of the capacitors being connected by a high-voltage diode having its cathode connected to the second capacitor.
Abstract:
During manufacturing of optical disks, mastering equipment inserts marks (nullhigh frequency wobble marksnull ornullHFWMsnull) into the wobble of the groove on optical disks to store data. The presence of a HFWM at a zero crossing of the wobble indicates an active bit and the absence of the HFWM indicates an inactive bit. The zero crossing is, for example, a negative zero crossing. A matched filter is used to detect the shape of the HFWMs. If a HFWM is detected during a wobble cycle, an active bit is saved in a register or a memory. If a HFWM is not detected during a wobble cycle, an inactive bit is saved in a register or a memory. The active and inactive bits may be coded bits that must be decoded to data bits. The data bits include information such as a synchronization mark, a sector identification data, and an error detection code.
Abstract:
The invention relates to a voltage controlled oscillator comprising a resonator having an inductive circuit and a capacitive circuit whose oscillations are maintained by an active circuit, the capacitive circuit using varactors whose capacitance is adjusted by a control voltage acting in a differential mode with a biasing voltage. According to the invention, the capacitive circuit comprises several capacitive branches connected in parallel, controlled by a same control voltage, but biased by biasing voltages that are different from one branch to the next. The oscillator of the invention features in particular an oscillation frequency, which is much easier to control, and a considerably reduced phase noise.
Abstract:
A control procedure is provided for use during a regulation stage and according to a set point of a physical dynamic system, the set point being subject to, whilst operating, the influence of several physical quantities represented by input parameters, and adopting a behavior defined by at least a first physical output parameter, obliged to take a value represented by the set point, the first output parameter being linked to at least a first of the input parameters by a first transfer function of the system. According to the control procedure, a characterization stage is implemented in which at least a first inverse transfer function linking the first input parameter to the first output parameter is experimentally determined. A modeling stage is implemented in which the first inverse transfer function is translated through a fuzzy logic model in the form of a first set of ranges of the first output parameter, to each of which is attributed a specific value of the first input parameter. The regulation stage is implemented by determining a membership of the set point to one of the ranges of the first set, deducing from the membership and from the fuzzy logic model an estimated value of the first input parameter corresponding to the desired equality between the first output parameter and the set point, producing a measured value of the first input parameter, and regulating the first input parameter according to a difference between the estimated value and the measured value of the first input parameter. The present invention is particularly suited for use with electric motors.
Abstract:
A system and method are provided for displaying a video composed of images each comprising a predetermined number M of lines and, a predetermined number N of pixels in each line. Values of a predetermined number P of reference pixels for each line of a current image of the video are stored in memory, where P is less than N. For each line of the current image, the value of a parameter associated with the line is determined, with the parameter corresponding to the number of the reference pixels of the line that are black according to a first predetermined criterion. A first nonblack line and a last nonblack line of the current image are determined to serve as a basis for an automatic reframing of the images of the video before display. The first nonblack line of the current image is determined by excluding, starting from a first line of the image, the lines of the image which are black according to a second predetermined criterion based on the parameter, and the last nonblack line of the current image is determined by excluding, starting from a last line of the image, the lines of the image which are black according to the second predetermined criterion based on the parameter.
Abstract:
A frequency/signal converter is provided that receives an input clock signal and generates an output signal. The converter includes a first circuit that receives the input clock signal and generates first and second logic signals that are complementary with one another, a loop circuit that includes a first circuit line and a second circuit line that are each coupled between a first supply voltage and a second supply voltage, and an integrator device. A current proportional to the output signal of the converter flows in the loop circuit. The first and second circuit lines include first and second capacitive elements and first and second switches for interrupting current flow into the first and second capacitive elements, respectively. The first and second switches are controlled by the first and second logic signals, respectively. The first and second circuit lines are alternatively coupled to an input terminal of the integrator device in order to obtain a substantially constant voltage signal at the input terminal of the integrator device, and the integrator device provides the output signal of the converter. Also provided is a switching regulator for providing a regulated voltage to a load.
Abstract:
The cells of the stacked type each comprise a MOS transistor formed in an active region of a substrate of semiconductor material and a capacitor formed above the active region; each MOS transistor has a first and a second conductive region and a control electrode and each capacitor has a first and a second plate separated by a dielectric region material, for example, ferroelectric one. The first conductive region of each MOS transistor is connected to the first plate of a respective capacitor, the second conductive region of each MOS transistor is connected to a respective bit line, the control electrode of each MOS transistor is connected to a respective word line, the second plate of each capacitor is connected to a respective plate line. The plate lines run perpendicular to the bit line and parallel to the word lines. At least two cells adjacent in a parallel direction to the bit lines share the same dielectric region material and the same plate line. In this way, the manufacturing process is not critical and the size of the cells is minimal.
Abstract:
A few times programmable (FTP) storage element is provided. The FTP storage element includes a set of N elementary memory units and multiple selection circuits. Each of the elementary memory units includes an address bus for connection to a main address bus and a data bus for connection to a main data bus. The selection circuits generate successive selection signals for successively selecting one of the elementary memory units in order to give exclusive access to the one selected elementary memory unit. The selection circuits operate so as to automatically select a next one of the elementary memory units upon detection of a predetermined condition. In preferred embodiments, each of the elementary memory units is programmable.
Abstract:
A biasing device includes closed-loop transconductance slaving circuit, able to slave the time average of the base/emitter or gate/source voltage of the amplifier transistor (Q1) to a reference voltage corresponding to a desired quiescent current for the transistor. Moreover, viewed from the base or gate of the amplifier transistor (Q1), the impedance of the base/emitter or gate/source circuit is small at low frequency, and large with respect to the impedance of the radio frequency source within the radio frequency range of the signal. The device can be incorporated in a mobile terminal, such as a cellular mobile phone.
Abstract:
A method for routing an information packet towards an output port of a telecommunication router comprising N output ports, said router receiving incoming packets comprising a destination address defined by four address elements. The method successively comprises: looking up a first-level table from said first address element of said information packet; looking up a second-level table from said first and second address elements of said packet; searching, with linear or dichotomizing search, a third-level table allowing a third level of search, from said third address element of said packet; searching, with linear or dichotomizing search, a fourth-level table from said fourth address element of said packet. In this way the size of the routing table can be reduced, while still allowing fast processing of incoming packets. The invention also provides a router allowing easy integration in a VLSI circuit.