Patent ID: 6157360
Filing Date: 2000-12-05
Classification: G09G

Abstract:
A system for driving a column of an active matrix display comprising:a resistor string digital-to-analog converter (DAC) for receiving a plurality of analog reference levels and generating multiple voltages by interpolation;a decoder for receiving the multiple voltages and selecting a single voltage from the multiple voltages; andan auto-stop buffer circuit for receiving the single voltage selected by the decoder and driving an output voltage toward the single voltage, wherein the output voltage is driven onto the column of the active matrix display;wherein the auto-stop buffer circuit includes a dead-zone amplifier;wherein the dead-zone amplifier actively drives the output voltage closer to the single voltage when there is a relatively substantial difference between the single voltage and the output voltage;wherein the dead-zone amplifier conserves power by automatically ceasing to actively drive the output voltage toward the single voltage when there is an insubstantial difference between the single voltage and the output voltage; andwherein the auto-stop buffer circuit further includes a passive conduit by way of which the output voltage is driven directly by the single voltage when the difference between the single voltage and the output voltage is insubstantial.