Thomson Multimedia S.a.

Stmicroelectronics S.a.

Sgs-thomson Microelectronics S.r.l.

Sgs-thomson Microelectronics S.a.

St-ericsson Sa

Frederic Paillardet

Francis Dell'Ova

Bruno Bonhoure

Pierre Busson

Martial Comminges

Sebastien Dedieu

Daniel Saias

Christian Delmas

Franck Montaudon

Isabelle Telliez

Jean-Francois Larchanche

A radio frequency transmission module is adapted to generate a first signal to be transmitted and to convert the signal to a radio frequency carrier for its radio transmission, in an operational phase, and is adapted to generate a second signal and to convert the second signal to the radio frequency carrier, in a calibration phase. The module includes a calibration unit having a subsampler adapted to subsample the second converted signal and a calculation unit adapted to calculate Fourier Transform coefficients representative of the signal delivered by the subsampler, for the purposes of processing the first signal to be transmitted, in the operational phase, as a function of at least some of the Fourier coefficients calculated in the calibration phase.

Calibration in a radio frequency transmission module

A dual-conversion tuner firstly upconverts so as to place itself outside the receive band and then downconverts with zero intermediate frequency. A filter of the surface acoustic wave type is disposed between the two frequency transposition stages of the tuner. After baseband filtering, the signals are digitized then processed in a digital block comprising a channel decoding module. With the exception of the surface acoustic wave filter, the components are entirely embodied in integrated fashion.

Electronic component allowing the decoding of digital terrestrial or cable television signals

An electronic circuit element has two capacitance values selected by means of a main control signal. The electronic circuit element comprises two variable-capacitance electronic components connected in parallel and each receiving opposite intermediate control signals, derived from the main control signal. The two variable-capacitance components are differentiated by a configuration parameter. The electronic circuit element exhibits a variation in capacitance corresponding to a difference between respective variations in capacitance of the two variable-capacitance electronic components during an inversion of the main control signal. The variation in capacitance of the electronic circuit element may be less than 5 attoFarads.

Variable-capacitance circuit element

A current amplifier includes a cascode transistor for fixing the voltage of an input of the amplifier; a first constant current source connected between the input and a first supply voltage; a second constant current source, for providing a current lower than the first current source, connected between a second supply voltage and the cascode transistor; a second transistor, of different type than the cascode transistor, connected between the input and the second supply voltage, and controlled by the node between the cascode transistor and the second current source; and an output transistor of same type as the second transistor, connected to the second supply voltage and controlled by the node.

Current amplifier

A digital sample filtering device comprising storage device including ROM and RAM memory for storing in an interlaced manner, coefficients of at least two filters along with for each coefficient, data indicating to which of the filters the each coefficient belongs; a multiplier for multiplying at least one of the coefficients by a sample and an accumulator for adding the partial sums of the multiplication results for each of the filters.

Digital filtering device

A digital-to-analog converter that includes pairs of positive and negative current sources that are connected through switches to two differential output lines. The switches are controlled as a function of a digital data. Each pair of current sources includes a pair of transistors of an output stage of a transconductance amplifier. The transconductance amplifier receives a reference voltage at a non-inverting input, and receives at an inverting input, the voltage at the middle node of a bridge of resistors that is connected between the two differential out-put lines. The output of the converter is the voltage between the two differential output lines.

Accurate digital-to-analog converter

The disclosure is an analog-to-digital converter of half-flash type providing for the multiplexing of two analog input signals and therefore requiring only one converter module. It includes a coarse comparator block used to determine the most significant bits of the converted signals and also determining the voltage range for two fine comparator blocks that determine the least significant bits of the converted signals, wherein each of the input signals is connected to a fine comparator block and said coarse comparator block compares alternatively the first and second input signals with a reference voltage. The analog-to-digital converter can be advantageously used for processing television signals.

Double-input analog-to-digital converter using a single converter module

The disclosure concerns a so-called 'auto-zeroing' comparator of two analog input voltages to be compared, and an analog-to-digital converter using a set of auto-zeroing comparators enabling the number of comparators required for an analog-to-digital conversion to be reduced. The main originality of the invention is that this comparator includes a second stage constituted by an inverter function provided in such a way that only a first transistor is controlled on its gate by the previous stage, a second transistor having its gate and drain short-circuited by a switch during the auto-zeroing phase, and a third transistor used as a capacitor and connected to the gate of said second transistor and also to the supply voltage. The present invention is applicable in particular to all types of CMOS multi-comparison ADCs using at least one 'auto-zeroing' comparator.

Growing community of inventors

Grenoble, France

Frederic Paillardet