摘要 |
Electrophoretic display units (1,100) are provided with switching circuits (50) to reduce the energy necessary for supplying data pulses (DP1, DP2) to pixels (11) via a data electrode (31,32,33,34). This energy is proportional to a differential voltage to be realised and to a capacitance (13) to be charged or discharged, which is formed by a combination of a capacitance of the pixel (11) and a capacitance of the active matrix. Due to this capacitance of the active matrix being much larger, a relatively large amount of energy is necessary. The switching circuit (50) couples the data electrode (31,32, 33,34) to a voltage reference source (REF) like ground between two selection pulses (SP1, SP2) to be supplied sequentially to two respective pixels (11) coupled to the same data electrode (31,32,33,34). This reduces the amount of discharging to be realized by the data drivers (3). As a result, the maximum energy necessary is reduced. To reduce the power consumption of the entire electrophoretic display unit (1,100), this should be done preferably for data pulses (DPI, DP2) having amplitudes with opposite polarity only.
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