Circuit and method for driving electro-optical panel, electro-optical device, and electronic equipment
AssigneeSeiko Epson Corporation
InventorToru Aoki
Life of this patent
Estimating the term…
Abstract
A video signal is sampled in response to a sampling signal, and is fed to a data line. The sampling signal is generated based on an enable signal EN. A timing control circuit includes a group of delay circuits for delaying a reference clock signal CLK, a selector circuit for selecting signals C1-C6 in response to a selection signal CTL, and an enable signal generator circuit for generating an enable signal based on an enable clock signal CLKe. The selection signal CTL is generated based on a phase difference signal M2, and has a constant fluctuation.
Claims25
A driving circuit for driving an electro-optical panel having a transistor and a pixel electrode at each intersection of each of a plurality of scanning lines and each of a plurality of data lines, comprising:
- a scanning line driving circuit which selects a scanning line to supply a transistor corresponding to the selected scanning line with a signal to turn on the transistor,
- a data line driving circuit which generates a shift pulse to select a data line within a duration during which the scanning title is selected, and limits the pulse width of the shift pulse to the pulse width of an enable pulse narrower than the shift pulse width and outputs the shift pulse with the narrow pulse width as a sampling signal,
- a sampling circuit which samples a video signal within the pulse duration of the sampling signal and feeds the sampled signal to at least one data line,
- a dummy circuit which is arranged adjacent to the sampling circuit and the data line driving circuit, and outputs a phase difference signal representing a phase difference between a monitor signal supplied in synchronization with the video signal and a reference pulse supplied in synchronization with the enable pulse, and
- an enable pulse adjustment circuit which adjusts the phase of the enable pulse so that the phase of the enable pulse leads with respect to the video signal when the phase difference signal indicates that the reference pulse lags the monitor signal in phase, or so that the phase of the enable pulse lags with respect to the video signal when the phase difference signal indicates that the reference pulse leads the monitor signal in phase.
An electro-optical device comprising an electro-optical panel and a timing control circuit, wherein the electro-optical panel comprises:
- a transistor at each intersection of each of a plurality of scanning lines and each of a plurality of data lines,
- a pixel electrode arranged corresponding to the transistor,
- a scanning line driving circuit which selects a scanning line to supply a transistor corresponding to the selected scanning line with a signal to turn on the transistor,
- a data line driving circuit which generates a shift pulse to select a data line, and limits the pulse width of the shift pulse to the pulse width of an enable pulse narrower than the shift pulse width and outputs the shift pulse with the narrower pulse width as a sampling pulse,
- a sampling circuit which samples a video signal within the pulse duration of the sampling signal within a duration during which the scanning line is selected and feeds the sampled signal to one data line,
- a dummy circuit which is arranged adjacent to the sampling circuit and the data line driving circuit, and outputs a phase difference signal representing a phase difference between a monitor signal supplied in synchronization with the video signal and a reference pulse supplied in synchronization with the enable pulse,
- wherein the timing control circuit comprises
- an enable pulse adjustment circuit which adjusts the phase of the enable pulse so that the phase of the enable pulse leads with respect to the video signal when the phase difference signal indicates that the reference pulse lags the monitor signal in phase, or so that the phase of the enable pulse lags with respect to the video signal when the phase difference signal indicates that the reference pulse leads the monitor signal in phase.
A driving method for driving an electro-optical panel having a transistor and a pixel electrode at each intersection of each of a plurality of scanning lines and each of a plurality of data lines, comprising the steps of:
- selecting a scanning line to supply a transistor corresponding to the selected scanning line with a signal to turn on the transistor,
- generating a shift pulse to select a data line within a duration during which the scanning line is selected, and limiting the pulse width of the shift pulse to the pulse width of an enable pulse narrower than the shift pulse width and outputting the shift pulse with the narrower pulse width as a sampling pulse,
- sampling a video signal within the pulse duration of the sampling signal and feeding the sampled signal to at least one data line,
- outputting a phase difference signal representing a phase difference between a monitor signal supplied in synchronization with the video signal and a reference pulse supplied in synchronization with the enable pulse, and
- adjusting the phase of the enable pulse so that the phase of the enable pulse leads with respect to the video signal when the phase difference signal indicates that the reference pulse lags the monitor signal in phase, or so that the phase of the enable pulse lags with respect to the video signal when the phase difference signal indicates that the reference pulse leads the monitor signal in phase.
Dependencies are inferred from the claim text.