| 摘要 |
An active matrix display device, such as an AMLCD, having sets of row and column address conductors ( 18, 19 ) connected to a row and column array of picture elements ( 12 ) and drive means ( 21, 23, 25 ) for supplying selection and data signals to the sets of rows and column address conductors respectively uses a plurality of serial charge redistribution digital to analogue conversion means ( 30 ) to convert multi-bit digital data signals supplied to the column address conductors ( 19 ) into analogue voltage levels for use by the picture elements. Each conversion means uses the capacitances of two column address conductors between which charge is shared by operation of conversion switches ( 31 ). The drive means is arranged to supply data signals alternately to the two column address conductors of each conversion means. This leads to a reduction in conversion errors and consequential unwanted display artefacts. Preferably, the column address conductor to which data signals are applied is changed after one or more complete multi-bit conversions performed by the conversion means. The required change over is accomplished using a simple switch arrangement.
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