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US 8,797,246 B2Granted
Driving circuit and voltage generating circuit and display unit using the same
AssigneeGold Charm Limited
InventorKatsumi Abe
Life of this patent
Estimating the term…
Abstract
A liquid crystal display substrate has a data driver circuit and a gate driver circuit for driving the liquid crystal display integrated thereon together with a common drive circuit, where common voltages VCOMH and VCOML are applied from the outside through a pad. The gate driver circuit is placed to be adjacent to one of the four terminals of the liquid crystal display. The common drive circuit is placed to be adjacent to the terminal opposite to where the gate driver circuit is placed and as close to the pad as possible while having almost the same width as the area of the gate driver circuit. The pad close to where the common drive circuit is placed is used as the pad for applying the common voltages VCOMH and VCOML.
Claims12
A voltage generating circuit for generating a providing voltage to a drive circuit comprising:
- a first and a second variable resistances for adjusting said providing voltage;
- a first operational amplifier outputting a high level of said providing voltage, and a non-inversion input thereof connected to a variable portion of said second variable resistance;
- a second operational amplifier outputting a low level of said providing voltage, and a non-inversion input thereof connected to a variable portion of said second variable resistance;
- a first resistance connecting a variable portion of said first variable resistances to an inversion input of said first operational amplifier;
- a second resistance wherein one terminal of said second resistance connected to said inversion input of said first operational amplifier, and the other terminal of said second resistance connected to output of said first operational amplifier;
- a third resistance connecting a constant voltage supply to an inversion input of said second operational amplifier;
- a fourth resistance wherein one terminal of said fourth resistance connects to a inversion input of said second operational amplifier, and the other terminal of said fourth resistance connects to an output of said second operational amplifier;
- wherein total resistance of said first variable resistance is a resistance value of one third or less of at least one of the total resistance of said second variable resistance and resistance of said first operational amplifier, said second operational amplifier, said first resistance, said second resistance, said third resistance, and said fourth resistance;
- and
- wherein said first and second variable resistances adjust a low level of said providing voltage and a voltage difference between a high level and the low level of said providing voltage.
7 more elements
A voltage generating circuit for generating a providing voltage to a drive circuit comprising:
- a first and a second variable resistances for adjusting said providing voltage;
- a first operational amplifier outputting a high level of said providing voltage, and a non-inversion input thereof connected to a variable portion of said second variable resistance;
- a second operational amplifier outputting a low level of said providing voltage, and a non-inversion input thereof connected to a variable portion of said second variable resistance;
- a first resistance connecting a variable portion of said first variable resistances to an inversion input of said first operational amplifier;
- a second resistance wherein one terminal of said second resistance connected to said inversion input of said first operational amplifier, and the other terminal of said second resistance connected to output of said first operational amplifier;
- a first capacitance, wherein one terminal of said first capacitance is connected to said output of said first operational amplifier, and the other terminal of said first capacitance connected to a constant voltage;
- a third resistance connecting a constant voltage supply to an inversion input of said second operational amplifier;
- a fourth resistance wherein one terminal of said fourth resistance connects to a inversion input of said second operational amplifier, and the other terminal of said fourth resistance connects to an output of said second operational amplifier;
- a second capacitance, wherein one terminal of said second capacitance is connected to said output of said second operational amplifier, and the other terminal of said second capacitance connected to the constant voltage,
- wherein total resistance of said first variable resistance is one third or less of at least one of the total resistance values of said second variable resistance and resistance of said first operational amplifier, said second operational amplifier, said first resistance, said second resistance, said third resistance, and said fourth resistance.
7 more elements
A display comprising:
- a substrate;
- a display portion integrated on said substrate;
- a gate driver circuit for controlling switching of pixels of each line in said display portion;
- a common drive circuit for said display portion for simultaneously driving capacitive loads in said display portion;
- and
- a common voltage generating circuit for generating a providing voltage to said common drive circuit, wherein said common voltage generating circuit and said common drive circuit are disposed at a position of said substrate opposite to said gate driver circuit, and said display portion is disposed between said common drive circuit and said gate driver circuit,
- a first and a second variable resistances for adjusting said providing voltage,
- a first operational amplifier outputting a high level of said providing voltage, and a non-inversion input thereof connected to a variable portion of said second variable resistance,
- a second operational amplifier outputting a low level of said providing voltage, and a non-inversion input thereof connected to a variable portion of said second variable resistance,
- a first resistance connecting a variable portion of said first variable resistances to an inversion input of said first operational amplifier,
- a second resistance wherein one terminal of said second resistance connected to said inversion input of said first operational amplifier, and the other terminal of said second resistance connected to output of said first operational amplifier,
- a third resistance connecting a constant voltage supply to an inversion input of said second operational amplifier, and
- a fourth resistance wherein one terminal of said fourth resistance connects to a inversion input of said second operational amplifier, and the other terminal of said fourth resistance connects to an output of said second operational amplifier,
- wherein total resistance of said first variable resistance is a resistance value of one third or less of at least one of the total resistance of said second variable resistance and resistance of said first operational amplifier, said second operational amplifier, said first resistance, said second resistance, said third resistance, and said fourth resistance;
- and
- wherein said first and second variable resistances adjust a low level of said providing voltage and a voltage difference between a high level and the low level of said providing voltage.
13 more elements
A display comprising:
- a substrate;
- a display portion integrated on said substrate;
- a gate driver circuit for controlling switching of pixels of each line in said display portion;
- a common drive circuit for said display portion for simultaneously driving capacitive loads in said display portion;
- and
- a common voltage generating circuit for generating a providing voltage to said common drive circuit, wherein said common voltage generating circuit and said common drive circuit are disposed at a position of said substrate opposite to said gate driver circuit, and said display portion is disposed between said common drive circuit and said gate driver circuit, wherein said common voltage generating circuit comprises:
- a first and a second variable resistances for adjusting said providing voltage;
- a first operational amplifier outputting a high level of said providing voltage, and a non-inversion input thereof connected to a variable portion of said second variable resistance;
- a second operational amplifier outputting a low level of said providing voltage, and a non-inversion input thereof connected to a variable portion of said second variable resistance;
- a first resistance connecting a variable portion of said first variable resistances to an inversion input of said first operational amplifier;
- a second resistance wherein one terminal of said second resistance connected to said inversion input of said first operational amplifier, and the other terminal thereof connected to output of said first operational amplifier;
- a first capacitance connected to said output of said first operational amplifier, and the other terminal thereof connected to a constant voltage;
- a third resistance connecting a constant voltage supply to an inversion input of said second operational amplifier;
- a fourth resistance wherein one terminal thereof connects to a inversion input of said second operational amplifier, and the other terminal thereof connects to an output of said second operational amplifier;
- a second capacitance wherein one terminal thereof connected to said output of said second operational amplifier, and the other terminal thereof connected to the constant voltage, wherein total resistance of said first variable resistance is one third or less of other resistance values.
12 more elements
Dependencies are inferred from the claim text.