Display device driver IC

• US 6,909,416 B2
• Filed: 09/23/2002
• Issued: 06/21/2005
• Est. Priority Date: 07/31/1998
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Aoki, Tadashi
• Primary Examiner(s): Shalwala, Bipin
• Assistant Examiner(s): Osorio, Ricardo
• Application Number:
  US10/251,972
• Publication Number:
  US 20030052849A1
• Time in Patent Office: 1,002 Days
• Field of Search: 345/87, 345/90, 345/91, 345/93, 345/94, 345/98, 345/100, 345/204
• US Class Current: 345/93
• CPC Class Codes: G09G 3/2074 using sub-pixels
• CPC Class Codes: G09G 3/3681 suitable for passive matrices only
• CPC Class Codes: G09G 3/3692 suitable for passive matrices only

Abstract

A driver IC (integrated circuit) for a display device allowing simple designing and production and yet capable of obviating display quality difference is provided. The driver IC includes a plurality of drive signal output terminals arrange to have variable drive capacities which vary depending on loads of respective signal electrodes of the display device to which the output terminals are connected so as to supply the respective signal electrodes of the display device with drive signal waveforms having identical time constant. The driver IC preferably includes a number of juxtaposed transistors corresponding to but larger in number than the drive signal output terminals, wherein the respective drive signal output terminals are connected to prescribed numbers of transistors so as to have different drive capacities depending on loads of the signal electrodes of the display device to which the output terminals are connected.

Claims

1. A driver IC (integrated circuit) for supplying drive signals to a plurality of signal electrodes arranged in one display device for driving the display device, wherein said driver IC comprises a plurality of drive signal output terminals having drive capacities which vary depending on loads of respective signal electrodes of the display device to which the output terminals are connected, so as to supply the respective signal electrodes arranged in one display device with drive signal waveforms having an identical time constant.

2. A driver IC for supplying drive signals to a plurality of signal electrodes arranged in one display device for driving the display device, wherein said driver IC comprises a plurality of drive signal output terminals arranged to have variable drive capacities which vary depending on loads of respective signal electrodes of the display device to which the output terminals are connected, so as to supply the respective signal electrodes arranged in one display device with drive signal waveforms having an identical time constant.

3. The driver IC according to claim 2, wherein the load of each signal electrode comprises a resistance of the signal electrode and capacitances of liquid crystal pixels formed along the signal electrode, and the display device comprises liquid crystal pixels having different capacities.