Patent ID: 6844874

Claim:
Matrix control device comprising: a plurality of elementary points; a source of first and second control signals; and a set of control circuits arranged in lines and columns for controlling states of elementary points, the state of each elementary point being a function of first and second control signals applied to a respective control circuit via the lines and columns, wherein each control circuit comprises a first input to receive the first control signal applied on a respective line, a second input which receives the second control signal applied on the respective column, and an output which is connected to a respective elementary point, wherein when a line is addressed, the first control signal applies to said first input a voltage pulse of a given value and duration followed by a voltage ramp signal during the corresponding line time on said line, the voltage ramp signal waveform varying linearly from a first voltage value to a second voltage value and over a duration greater than the voltage pulse duration, the voltage pulse operating to activate all the control circuits of the corresponding line by turning them on, so that the output of the control circuits can then follow the voltage ramp signal waveform, until the second control signal applied on the columns turns off the activated control circuits, said second control signal being a switching signal of digital type for determining the duration for which the activated control circuits remain on.