Patent ID: 6069577
Filing Date: 2000-05-30
Classification: H03M

Abstract:
An A/D conversion device having an input intended to receive an analog input signal, and an output intended to supply a digital output signal, comprising:an amplifier having an input intended to receive the analog input signal of the device, and an output,an A/D converter having an analog input connected to the output of the amplifier and an output intended to supply the digital output signal of the device, comprising a resistance ladder traversed by a current supplied by a controllable bias current source, the junction points in said ladder supplying a plurality of reference voltages intended to be compared with the signal received at the input of the converter, the results of these comparisons being used to generate the digital output signal of the device,said conversion device being characterized in that it has an input intended to receive a calibration signal, and in that it comprises means for setting the input of the amplifier at a predetermined reference potential when the calibration signal is active, and a calibration arrangement comprising:a comparison module, activated when the calibration signal is active, comprising a comparator intended to supply, at an output, a signal which is representative of at least one comparison between the digital output signal and a predetermined binary word,a control module having an input connected to the output of the comparison module and being activated when the calibration signal is active, intended to supply a digital control signal, whose value depends on the value of a signal received at the input of the control module, and intended to effect a variation of the value of the current supplied by the bias current source, andstorage means in which the value of the control signal is stored when the calibration signal is inactive.