The general field of the invention is that of touchscreen devices with projected capacitive detection comprising a matrix touchpad comprising a plurality of conducting rows and of conducting columns, the matrix touchpad linked to an emission voltages electronic control system and a reception voltages electronic system. The emission voltages electronic control system generates two periodic emission voltages emitted at two different frequencies. The analysis of the reception voltages, by the reception voltages electronic system, makes it possible to determine the positions of two simultaneous presses on the touchpad, including when the two presses are done on rows or columns that are close. The determination of the presses is performed essentially by calculating the barycenters of the troughs of the reception voltages.