Abstract:
A fuel cell having its active stack resting on a thin conductive layer, bearing on a wafer provided with through gas inlet channels, the thin conductive layer protruding in the active stack in front of each channel and being transparent to the gas.
Abstract:
A method for sampling an analogue radiofrequency signal comprising reception of the analogue radiofrequency signal, sending of the received signal on two analogue channels, each channel performing a first signal sampling operation, including a filtering step eliminating signal frequencies that could fold on the useful signal during sampling such that the sampled signal represents a filtered version of the received signal, wherein the sampling frequency is taken to be equal to the frequency of the signal carrier divided by a factor Ndiv1+½, Ndiv1 being an integer number, to bring the useful signal to half of the sampling frequency after sampling.
Abstract:
A circuit for generating a cyclic prefix of a symbol comprised of a sequence of time samples, the prefix being the reproduction of the last samples of the symbol at the beginning of the symbol, the symbol being obtained by inverse Fourier transform of complex coefficients corresponding to respective frequencies. The circuit includes a multiplier that shifts the phase of each complex coefficient by a value proportional to its frequency, a memory for storing the samples at the beginning of the symbol, and a multiplexer that copies at the end of the symbol the stored samples.
Abstract:
A heterodyne receiving circuit for a digital communication system including a first band pass filter receiving a signal from an antenna, an amplifying circuit and a second narrow band pass filter for selecting one particular channel within a band of frequencies. The two filters are carried out with integrated BAW-type tunable resonators which can be adjusted, respectively, by a first electrical signal and a second electrical signal generated by two PLL-type frequency control loops. The second frequency control loop has a variable division factor for the purpose of selecting one particular channel within said band of frequencies. In addition, the receiving circuit includes a mixer for mixing the signal generated at the output of said second filter with a local oscillation frequency in order to produce an intermediate frequency. The division factor is controlled by a digital processing of the intermediate frequency.
Abstract:
A circuit includes a memory cell having a high voltage supply node and a low voltage supply node. Power multiplexing circuitry is included to selectively apply one of a first set of voltages and a second set of voltages to the high and low voltage supply nodes of the cell in dependence upon a current operational mode of the cell. If the cell is in active read or write mode, then the multiplexing circuitry selectively applies the first set of voltages to the high and low voltage supply nodes. Conversely, if the cell is in standby no-read or no-write mode, then the multiplexing circuitry selectively applies the second set of voltages to the high and low voltage supply nodes. The second set of voltages are offset from the first set of voltages. More particularly, a low voltage in the second set of voltages is higher than a low voltage in the first set of voltages, and wherein a high voltage in the second set of voltages is less than a high voltage in the first set of voltages. The cell can be a member of an array of cells, in which case the selective application of voltages applies to the array depending on the active/standby mode of the array. The array can include a block or section within an overall memory device including many blocks or sections, in which case the selective application of voltages applies to individual blocks/sections depending on the active/standby mode of the block/section itself.
Abstract:
A method for detecting a malfunction in a state machine is described. The state machine has an operation modeled by a set of states linked to each other by transitions, the state machine generating, upon each transition, output signals according to input signals comprising signals generated during a previous transition. During a transition, the method comprises steps of generating at least one control signal according to a control signal generated during a previous transition, determining an expected value of the control signal, and comparing the control signal with the expected value.
Abstract:
A binary frequency divider includes a counter paced by an input signal, means for comparing a counting value with first and second threshold values and supplying first and second control signals synchronized with variation edges of a first type of the input signal. The divider includes means for supplying at least one third control signal shifted by a half-period of the input signal in relation to one of the first or second control signals, and control means for generating the output signal using control signals chosen according to the value of at least one least significant bit of the division setpoint. Application is mainly but not exclusively to UHF transponders.
Abstract:
A filtering circuit with BAW type acoustic resonators having at least a first quadripole and a second quadripole connected in cascade, each quadripole having a branch series with a first acoustic resonator of type BAW and a branch parallel with each branch having an acoustic resonator of type BAW, the first acoustic resonator having a frequency of resonance series approximately equal to the frequency of parallel resonance of the second acoustic resonator, the branch parallel of the first quadripole having a first capacitance connected in series with the second resonator and, in parallel with the capacitance, a first switching transistor to short circuit the capacitance.
Abstract:
A system for detecting the time exceeding conditions of at least one application being executed by a processor, including: an element for storing time conditions, the conditions being sorted by increasing deadline order; a register for storing the condition closest to the current date; and a comparator of the deadline contained in the register with the current date of the system.
Abstract:
A RAM memory integrated circuit, in particular a SRAM memory integrated circuit, includes a matrix of memory cells that are arranged between two bit lines via two access transistors. The bit lines are intended in one case to be discharged and in the other case to be maintained at a high precharge potential during a read operation. The bit line of each column of the matrix that is intended to be maintained at the high precharge potential is produced in the form of at least two partial bit lines. The memory cells of each column are implanted in the form of groups of cells which are alternately connected to one or the other of the partial bit lines, respectively.