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Operational amplifier circuit and display apparatus

A technology of an operational amplifier circuit and amplifying part, which is applied to amplifiers, differential amplifiers, and improved amplifiers to reduce temperature/power supply voltage changes, etc. The effect of reducing the area, suppressing the increase of the circuit area, and reducing the output voltage deviation

Inactive Publication Date: 2010-05-26
PANASONIC CORP
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Therefore, if you want to suppress the deviation of the output voltage to about a few mV by improving the manufacturing process, it will take too much cost and time, and it is relatively difficult in reality.
[0017] In addition, as described in Patent Document 1, when the output voltage deviation is reduced by adding circuits, the circuit area of ​​the display driving device also increases.

Method used

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  • Operational amplifier circuit and display apparatus
  • Operational amplifier circuit and display apparatus

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Embodiment 1

[0103] In Embodiment 1 of the present invention, for figure 2 One embodiment of operational amplifier circuit 122 is shown as operational amplifier circuit 122A for illustration.

[0104] Figure 4 It is a diagram for comparison, and is a circuit diagram of a general operational amplifier circuit 222 .

[0105] Figure 4 The illustrated operational amplifier circuit 222 is an operational amplifier having inverting and non-inverting input terminals and an output terminal Vout.

[0106] The inverting input terminal is connected to the output terminal Vout. Accordingly, the operational amplifier circuit 222 outputs the voltage value applied to the non-inverting input terminal to the output terminal Vout.

[0107] This operational amplifier circuit 222 has a differential amplification unit 31 (differential stage) and an output unit 32 (output stage).

[0108] The differential amplifier 31 amplifies the voltage difference between the voltage of the inverting input terminal an...

Embodiment 2

[0179] In embodiment 2 of the present invention, for figure 2 One embodiment of operational amplifier circuit 122 is shown, operational amplifier circuit 122B, for illustration.

[0180] Figure 9 It is a circuit diagram of the operational amplifier circuit 122B according to the second embodiment of the present invention. And, for Figure 5 The same elements are assigned the same symbols, and repeated explanations are omitted here.

[0181] Figure 9 The operational amplifier circuit 122B is shown with Figure 5 In contrast to the configuration of the illustrated operational amplifier circuit 122A, a variable resistance unit 15B is provided instead of the variable resistance unit 15A. This variable resistance unit 15B has a variable resistance element 21 and a correction polarity switching circuit 61 .

[0182] The variable resistance element 21 is connected between the source of the differential transistor 100 on the non-inverting input side and the source of the diffe...

Embodiment 3

[0230] In Embodiment 3 of the present invention, for figure 2 One embodiment of operational amplifier circuit 122 is shown as operational amplifier circuit 122C for illustration.

[0231] Figure 12 is a circuit diagram of an operational amplifier circuit 122C according to Embodiment 3 of the present invention. For with Figure 5 The same symbols are given to the same elements, and repeated explanations are omitted.

[0232] Figure 12 The operational amplifier circuit 122C shown in addition has Figure 5 In addition to the configuration of the operational amplifier circuit 122A shown, variable current sources 81 and 82 are included.

[0233] The variable current source 81 is connected between the source of the differential transistor 100 on the non-inverting input side and a bias voltage, and supplies positive or negative current Icp to the source of the differential transistor 100 on the non-inverting input side. Furthermore, the variable current source 81 selectively...

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Abstract

An operational amplifier circuit according to an aspect of the present invention includes a differential amplifier unit. The differential amplifier circuit includes a first differential transistor and a second differential transistor, which form a first differential pair, and a current source transistor which supplies a current to the first differential pair. The operational amplifier circuit further includes a first variable resistive element connected between (i) at least one of sources of the first and the second differential transistors and (ii) a drain of the current source transistor. The first variable resistive element includes: a first terminal and a second terminal; first resistive elements connected in series; and a first correction voltage selecting circuit which modifies a resistance value between the first and the second terminals by changing the number of stages of the first resistive elements connected in series between the first and the second terminals.

Description

technical field [0001] The present invention relates to an operational amplifier circuit and a display device, and more particularly to an operational amplifier circuit including a differential amplifier. Background technique [0002] In recent years, liquid crystal panels and organic EL (organic electroluminescence: electroluminescence) panels have been used in portable devices, small mobile devices, and large panel devices. In addition, liquid crystal panels and organic EL (electroluminescent) panels are used in display devices in the field of video equipment such as televisions, which are expanding in market. In such display devices, multi-gradation (8bit→10bit→12bit) and high-quality display panels are being promoted in order to get closer to natural image quality. Furthermore, in the display driver LSI included in the display device, it is required to reduce the non-uniformity (variation) of the output voltage between the output terminals. [0003] For example, Patent...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): H03F3/45H03F1/30G09G3/20G09G3/32
CPCH03F2203/45674H03F3/45183
Inventor 小川宗彦西和义小岛宽小岛友和
Owner PANASONIC CORP
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