Data line drive circuit for display devices
AssigneePanasonic Corporation
InventorsTomokazu KOJIMA, Munehiko OGAWA, Yoshiyuki OTANI
Life of this patent
Estimating the term…
Abstract
(M+N) drive circuits each perform impedance conversion on an input voltage to output the resultant voltage. A selector selects M drive circuits having a predetermined output voltage accuracy from the (M+N) drive circuits, supplies M display voltages to inputs of the selected M drive circuits, and outputs, as M drive voltages, outputs of the selected M drive circuits.
Claims8
A data line drive circuit for outputting M drive voltages for driving M data lines of a display device, where M is an integer of two or more, comprising:
- (M+N) drive circuits each configured to perform impedance conversion on an input voltage and output the resultant voltage, where n is an integer of one or more;
- and
- a selector configured to select M drive circuits having a predetermined output voltage accuracy from the (M+N) drive circuits, supply M display voltages based on image data to be displayed on the display device to inputs of the selected M drive circuits, and output, as the M drive voltages, outputs of the selected M drive circuits, wherein
- the (M+N) drive circuits include
- (M+N) differential amplifier transistor pairs,
- M active loads each configured to serve as an active load for an operational amplifier, and
- M output driver/current mirror sections each configured to serve as an output circuit for an operational amplifier and as a current mirror circuit configured to input a bias to the corresponding differential amplifier transistor pair, and
- M differential amplifier transistor pairs selected from the (M+N) differential amplifier transistor pairs by the selector, the M active loads, and the M output driver/current mirror sections form M negative feedback operational amplifiers.
A data line drive circuit for outputting M drive voltages for driving M data lines of a display device, where M is an integer of two or more, comprising:
- (M+N) drive circuits each configured to perform impedance conversion on an input voltage and output the resultant voltage, where n is an integer of one or more;
- and
- a selector configured to select M drive circuits having a predetermined output voltage accuracy from the (M+N) drive circuits, supply M display voltages based on image data to be displayed on the display device to inputs of the selected M drive circuits, and output, as the M drive voltages, outputs of the selected M drive circuits, wherein
- the (M+N) drive circuits include
- (M+N) differential amplifiers each configured to serve as a differential amplifier for an operational amplifier, and
- M output driver/current mirror sections each configured to serve as an output circuit for an operational amplifier and as a current mirror circuit configured to input a bias to the corresponding differential amplifier transistor pair, and
- M differential amplifiers selected from the (M+N) differential amplifiers by the selector and the M output driver/current mirror sections form M negative feedback operational amplifiers.
Dependencies are inferred from the claim text.