Patent ID: 6320565
Filing Date: 2001-11-20
Classification: G09G,H04N

Abstract:
A driver circuit for an electro-optic display device comprising an active row-and-column matrix array of pixels, the driver circuit comprising:a control circuit for sequentially addressing the pixels of the device with analog display signals, the control circuit comprising selection means for selecting a row of pixels during a row selection period, and writing means for applying the analog signals to the selected pixels over one or more columns during the row selection period;a DAC for converting a stream of incoming digital display signals into the analog display signals, the DAC including a ramp generator for generating an analog ramp down from a high value to a low value during the row selection period, and sample-and-hold means for selecting an analog signal from the ramp corresponding to the sampled digital signal, and holding the analog signal for application to the selected pixels;characterized in that the selection means of the control circuit is set to simultaneously with the selecting a row of pixels during a row selection period, selecting pixels to be reset to a pre-determined state prior to writing, and the writing means is set to apply a resetting pulse from the analog ramp generator to the selected pixels prior to selection of the analog information signals from the DAC, whereby the artifacts caused by the residual state of the electro-optic material are reduced or eliminated.