Patent ID: 9373297
Filing Date: 2016-06-21
CPC Classification: G09G

Claim Text:
1. A display driver circuit having selectable grayscale and bi-level modes, comprising: a digital to analog converter (DAC); a first video amplifier configured to receive an input signal from the DAC and to provide a first output signal to a first node; a first set of level switches including a second video amplifier configured to receive the input signal from the DAC and to provide a second output signal to a second node; a second set of level switches including an enable circuit having a grayscale mode, enabling the DAC and the first and second video amplifiers, and a bi-level mode, enabling a subset of the first, second, third and fourth switches and disabling the DAC and first and second video amplifiers; a first capacitor configured to AC couple the first node to a first video path; and a second capacitor configured to AC couple the second node to a second video path; the enable circuit being configured to perform an extended direct current restore mode characterized by: (i) when the first video amplifier provides the first output signal to the first node, using the second set of level switches to set the second node to a first direct current level; and (ii) when the second video amplifier provides the second output signal to the second node, using the first set of level switches to set the first node to a second direct current level.