Method and apparatus for selective enabling of addressable display elements

Abstract

A method and apparatus for driving a plurality of addressable elements consist of driving and selectively enabling one or more addressable elements arranged as an M×N array using two drivers. The columns may be addressed in parallel. Columns may be coupled to a conductor by a charge transfer/isolation circuit. A voltage waveform or pulse train may be propagated down the display conductor such that a pulse is present on the display conductor for each element of a row of elements to be addressed. When the beginning of the pulse train has propagated to the last column tap-off point so that a different pulse is present at each column tap-off point corresponding to the row of elements to be selected, a corresponding charge is transferred to each column conductor in parallel. Thus, a voltage is supplied to select each element on the selected row as determined by the state of the pulse train at each column tap-off point. During the time the voltages are supplied to the column conductors, the column conductors are isolated from the column tap-off points so that a next pulse train corresponding to the next element row may be propagated down the conductor. The rows may be selected by any row addressing technique, such as individual row drivers, or a beat-frequency technique employing only two row drivers.