A charge transfer recursive filter

As all the weighting coefficients of the filter are positive, a weighted charge quantity is collected by a line beneath one of the elementary electrodes of each weighting electrode. A charge reading device is coupled to the line and supplies an electrical signal which is transmitted to the negative input of a differential amplifier, which receives the sampled input voltage of the filter at its positive input. The electrical output signal of the filter is taken, under low impedance, at the output of the differential amplifier, said signal being reinjected at the input of the filter by the injecting means.