CN101393730B - Gamma voltage conversion apparatus - Google Patents

Gamma voltage conversion apparatus Download PDF

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Publication number
CN101393730B
CN101393730B CN2008101757812A CN200810175781A CN101393730B CN 101393730 B CN101393730 B CN 101393730B CN 2008101757812 A CN2008101757812 A CN 2008101757812A CN 200810175781 A CN200810175781 A CN 200810175781A CN 101393730 B CN101393730 B CN 101393730B
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resistance
gamma
gamma voltage
operational amplifier
coupled
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CN101393730A (en
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柯明道
陈绍岐
李宇轩
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AU Optronics Corp
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AU Optronics Corp
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Abstract

A device for converting the Gamma voltage comprises a Gamma voltage conversion circuit, an amplifier and a Gamma voltage regulating circuit, wherein the Gamma voltage conversion circuit is used for generating a first Gamma voltage in accordance with a first Gamma curve according to gray scale signals; the amplifier comprises a first input terminal used for the first Gamma voltage, a second input terminal and an output terminal; the amplifier outputs the first Gamma voltage or the second Gamma voltage of a second Gamma curve as the Gamma driving voltage according to the first input terminal and the second input terminal; and the Gamma voltage regulating circuit is coupled between the second input terminal and the output terminal of the amplifier, and used for controlling the amplifier to output the first or the second Gamma voltage as the Gamma driving voltage according to the gray scale signal and the Gamma curve selection signal.

Description

Gamma voltage conversion apparatus
[technical field]
The present invention is relevant a kind of gamma voltage conversion apparatus, more particularly, is relevant a kind of gamma voltage conversion apparatus that a GTG conversion of signals can be become meet the gamma voltage of a gamma curve or another gamma curve.
[background technology]
Please refer to Fig. 1.Fig. 1 is the synoptic diagram of explanation one gamma curve (gamma curve).In Fig. 1, gamma curve gamma A is applicable to that 3 volts liquid crystal panel, transverse axis represent GTG signal D IN, the longitudinal axis represents gal sign indicating number driving voltage V OUT, and GTG signal D INIt is the digital signal of one or six bits (6bits).Therefore the user can learn GTG signal D according to the gamma curve gamma A that is disclosed among Fig. 1 INThe gamma driving voltage V that is corresponded to OUTSize, drive 3 volts liquid crystal panel with this.
Please refer to Fig. 2.Fig. 2 is the synoptic diagram of the gamma voltage conversion apparatus 200 of a prior art.As shown in Figure 2, gamma voltage conversion apparatus 200 comprises a gamma voltage change-over circuit 210 and an operational amplifier OP.
Gamma voltage change-over circuit 210 is used for according to a GTG signal D IN, output one meets the gamma voltage V of gamma curve gammaA GATo operational amplifier OP, operational amplifier OP exports gamma driving voltage V more according to this OUTTo drive 3 volts liquid crystal panel.GTG signal D wherein INIt is the digital signal of one or six bits.
Gamma voltage change-over circuit 210 comprises 211,64 switch SW of a code translator A1～SW A64, and a resistance serial 212.
Resistance serial 212 is coupled to a reference voltage source V REFAn and bias generator V SSBetween (hold).Resistance serial 212 comprises the resistance R of 65 series connection A0～R A64, wherein each resistance has a predetermined resistance, is used to provide an electric resistance partial pressure (electric resistance partial pressure V as shown in Figure 2 1～V 64) (64 electric resistance partial pressures are provided altogether), and electric resistance partial pressure that each resistance provided and GTG signal D INCorresponding relation meet gamma curve gamma A.For instance, as GTG signal D INDuring for [000000], be V according to the pairing electric resistance partial pressure of gamma curve gamma A 1, as GTG signal D INDuring for [000001], be V according to the pairing electric resistance partial pressure of gamma curve gamma A 2As GTG signal D INDuring for [111111], be V according to the pairing electric resistance partial pressure of gamma curve gammaA 64
Code translator 211 is used for receiving GTG signal D IN, and decipher out corresponding decoded signal D according to this 01～D 064As aforementioned GTG signal D INBe six bits, as GTG signal D INDuring for [000000], then has only decoded signal D 01For logical one, all the other decoded signals are logical zero; As GTG signal D INDuring for [000001], then has only decoded signal D 02For logical one, all the other decoded signals are logical zero ... as GTG signal D INDuring for [111111], then has only decoded signal D 064For logical one, all the other decoded signals are logical zero.
Switch S WA1～SW A64Be used for respectively decoded signal D according to code translator 211 01～D 064, send resistance serial 212 electric resistance partial pressure that provides to operational amplifier OP.Switch S WA1～SW A64In each switch all comprise one first end 1, one second end 2, an and control end C.Switch SW A1～SW A64In first end 1 of each switch be coupled to resistance corresponding in the resistance serial 212, to receive corresponding electric resistance partial pressure, switch SW A1～SW A64In second end 2 of each switch be coupled to the first input end (positive input terminal) of operational amplifier OP, the electric resistance partial pressure that is used for being received (is the gamma voltage V that gamma voltage change-over circuit 210 is exported GA) be sent to operational amplifier OP with as input voltage V IN1, switch SW A1～SW A64In the control end C of each switch output terminal that is coupled to code translator 211 correspondences receiving corresponding decoded signal, with gauge tap SW according to this A1～SW A64 First end 1 and second end 2 couple.More particularly, all switch SW A1～SW A64All be shorted to this first input end that computing is amplified.For instance, as GTG signal D INDuring for [000000], then has only decoded signal D 01For logical one, all the other decoded signals are logical zero, therefore has only switch SW A1Be unlocked and with electric resistance partial pressure V 1Be sent to this first input end of operational amplifier OP, the meaning gamma voltage V that promptly this moment, gamma voltage change-over circuit 210 was exported GABe V 1And input voltage V as operational amplifier OP IN1As GTG signal D INDuring for [000001], then has only decoded signal D 02For logical one, all the other decoded signals are logical zero, therefore has only switch SW A2Be unlocked and with electric resistance partial pressure V 2Be sent to this first input end of operational amplifier OP, the meaning gamma voltage V that promptly this moment, gamma voltage change-over circuit 210 was exported GABe V 2And input voltage V as operational amplifier OP IN1As GTG signal D INDuring for [111111], then has only decoded signal D 064For logical one, all the other decoded signals are logical zero, therefore has only switch SW A64Be unlocked and with electric resistance partial pressure V 64Be sent to this first input end of operational amplifier OP, the meaning gamma voltage V that promptly this moment, gamma voltage change-over circuit 210 was exported GABe V 64And input voltage V as operational amplifier OP IN1
Operational amplifier OP comprises a first input end (positive input terminal), one second input end (negative input end), and an output terminal.This output terminal of operational amplifier OP is coupled to this second input end (negative input end) of operational amplifier OP, so so that operational amplifier OP forms a voltage follower (voltagefollower), be used for the voltage V that this first input end (positive input terminal) to operational amplifier OP received IN1Export gamma driving voltage V in the output terminal of operational amplifier OP again after cushioning OUTTo strengthen driving force.The input voltage V of operational amplifier wherein IN1With gamma driving voltage V OUTEqual and opposite in direction, that is to say the gamma driving voltage V of last output OUTCan equal the gamma voltage V that gamma voltage change-over circuit 210 is exported GA
Therefore, according to above-mentioned, gamma voltage conversion apparatus 200 just can convert the gamma driving voltage V that meets gamma curve gamma A to according to the GTG signal that is received OUT, drive 3 volts liquid crystal panel.
Yet because the gamma voltage conversion apparatus 200 of prior art, the resistance of each resistance in its resistance serial has configured all so that corresponding electric resistance partial pressure can meet gamma curve gamma A.Yet, the liquid crystal panel of other type must gamma curve be not to be gamma curve gamma A, for instance, 5 volts liquid crystal panel is applicable to gamma curve gamma B.Therefore, the gamma voltage conversion apparatus 200 of prior art is only applicable to 3 volts liquid crystal panel and can't be applicable to 5 volts liquid crystal panel, causes the user in the application of plurality of liquid crystals panel, produces inconvenience.
[summary of the invention]
The invention provides a kind of gamma voltage conversion apparatus, be used for, produce a corresponding gamma driving voltage according to a GTG signal.This GTG signal and this gamma driving voltage meet one first gamma curve or one second gamma curve.This gamma voltage conversion apparatus comprises a gamma voltage change-over circuit, an operational amplifier and a gamma voltage and adjusts circuit.This gamma voltage change-over circuit is used for producing one first gamma voltage according to this GTG signal.This GTG signal and this first gamma voltage meet this first gamma curve.This operational amplifier comprises a first input end, is coupled to this gamma voltage change-over circuit, is used for receiving this first gamma voltage, one second input end, and an output terminal.This operational amplifier is according to this first input end of this operational amplifier and this second input end of this operational amplifier, exports this first gamma voltage or one second gamma voltage with as this gamma driving voltage.This GTG signal and this second gamma voltage meet this second gamma curve.This gamma voltage is adjusted between this output terminal that circuit is coupled to this second input end of this operational amplifier and this operational amplifier, be used for selecting signal, control this operational amplifier and export this first gamma voltage or this second gamma voltage with as this gamma driving voltage according to this GTG signal and a gamma curve.
[description of drawings]
Fig. 1 is the synoptic diagram of explanation one gamma curve.
Fig. 2 is the synoptic diagram of the gamma voltage conversion apparatus of a prior art.
Fig. 3 is the synoptic diagram of explanation two gamma curve.
Fig. 4 is the synoptic diagram of gamma voltage conversion apparatus of the present invention.
Fig. 5 is the synoptic diagram of an embodiment of explanation code translator of the present invention.
Fig. 6 is the synoptic diagram of an embodiment of explanation another code translator of the present invention.
Fig. 7,8,9 is for illustrating the synoptic diagram of importing the operation principles of gamma voltage conversion apparatus of the present invention when a GTG signal.
[primary clustering symbol description]
Gamma A, gamma B gamma curve
V OUTThe gamma driving voltage
V GA, V GBGamma voltage
D INThe GTG signal
B 1～B 6Bit
The OP operational amplifier
D 01～D 064, D X1～D X37Decoded signal
G SGamma curve is selected signal
V IN1, V IN2Input voltage
R A0～R A64, R B1～R B37, R X, R VResistance
V 1～V 64Electric resistance partial pressure
V REFReference voltage source
V SSBias generator
S WA1～SW A64, SW B1～SW B37, S WGSwitch
AND 1～AND 64With door
INV 1～INV 6Phase inverter
200,400 gamma voltage conversion apparatus
500 voltage conversion circuits
210,410 gamma voltage change-over circuits
212,412,4212 resistance serials
421 variable resistance circuit
211,411,4211 code translators
420 gamma voltages are adjusted circuit
[embodiment]
Please refer to Fig. 3.Fig. 3 is the synoptic diagram of explanation two gamma curve.In Fig. 3, gamma curve gammaA is applicable to that 3 volts liquid crystal panel, liquid crystal panel, the transverse axis that gamma curve gamma B is applicable to 5 volts represent GTG signal D IN, the longitudinal axis represents gal sign indicating number driving voltage V OUT, and GTG signal D INIt is the digital signal of one or six bits.Therefore the user can learn GTG signal D according to the gamma curve gamma A that is disclosed among Fig. 3 INThe gamma driving voltage V that is corresponded to OUTSize, drive 3 volts liquid crystal panel with this; The user also can learn GTG signal D according to the gamma curve gamma B that is disclosed among Fig. 3 INThe gamma driving voltage V that is corresponded to OUTSize, drive 5 volts liquid crystal panel with this.
Please refer to Fig. 4.Fig. 4 is the synoptic diagram of gamma voltage conversion apparatus 400 of the present invention.As shown in Figure 4, gamma voltage conversion apparatus 400 comprises a gamma voltage change-over circuit 410, a gamma voltage is adjusted circuit 420, and an operational amplifier 0P.Gamma voltage conversion apparatus 400 can be used to the setting according to the user, selects employed gamma curve gamma A or gamma B, is used to drive 3 volts liquid crystal panel or 5 volts liquid crystal panel with the gamma driving voltage that will be exported.
Gamma voltage change-over circuit 410 is used for according to a GTG signal D IN, output one meets the gamma voltage V of gamma curve gammaA GATo operational amplifier OP with input voltage V as operational amplifier OP IN1Gamma voltage change-over circuit 410 comprises 411,64 switch SW of a code translator A1～SW A64, and a resistance serial 412.Gamma voltage change-over circuit 410 is similar with the structure and the operation principles of gamma voltage change-over circuit 210, repeats no more in this.
Operational amplifier OP comprises a first input end (positive input terminal), one second input end (negative input end), and an output terminal.This first input end (positive input terminal) of operational amplifier OP is used for receiving input voltage V IN1, operational amplifier OP this second input end (negative input end) be used for receiving input voltage V IN2, and this output terminal gamma driving voltage V of operational amplifier OP OUTIn Fig. 4, input voltage V IN1Can equal the gamma voltage V that gamma voltage change-over circuit 410 is exported GASince the characteristic of operational amplifier OP, the input voltage V on its first input end (positive input terminal) IN1Can be equal to the input voltage V on its second input end (negative input end) in fact IN2
Gamma voltage is adjusted circuit 420 and is comprised a gamma curve selector switch SW G, a resistance R X, and a variable resistance circuit 421.
Variable resistance circuit 421 comprises a code translator 4211, a resistance serial 4212, and 37 switch SW B1～SW B37
Code translator 4211 is used for the decoded signal D that deciphered out according to code translator 411 01～D 064, decipher out decoded signal D again X1～D X37
Switch SW B1～SW B37Be used for respectively decoded signal D according to code translator 4211 X1～D X37, controlling resistance serial 4212 integral body are for the equivalent resistance of operational amplifier OP.More particularly, resistance serial 4212 can be considered a variable resistor R V, be coupled to this second input end and the bias generator V of operational amplifier OP SSBetween (hold), and switch SW B1～SW B37Can be used to control the resistance size of variable resistor RV.Switch SW B1～SW B37In each switch all comprise one first end 1, one second end 2, an and control end C.Switch SW B1～SW B37In first end 1 of each switch be coupled to resistance, switch SW corresponding in the resistance serial 4212 B1～SW B37In second end 2 of each switch couple bias generator V SS(hold), switch SW B1～SW B37In the control end C of each switch be coupled to the output terminal of code translator 4211 correspondences to receive corresponding decoded signal, with gauge tap SW B1～SW B37 First end 1 and second end 2 couple.
Resistance serial 4212 is coupled to this second input end (negative input end) and switch SW of operational amplifier OP B1～SW B37Between.Resistance serial 4212 comprises the resistance R of 37 series connection B1～R B37, wherein each resistance has a predetermined resistance.As previously mentioned, resistance serial 4212 can be considered a variable resistor R V, be coupled to this second input end and the bias generator V of operational amplifier OP SSBetween (hold), and switch SW B1～SW B37Can be used to control variable resistor R VThe resistance size.For instance, as decoded signal D X1For logical one to open switch SW B1The time, variable resistor R VThe resistance size equal resistance R B1The resistance size; As decoded signal D X2For logical one to open switch SW B2The time, variable resistor R VThe resistance size equal resistance (R B1+ R B2) the resistance size; As decoded signal D X3For logical one to open switch SW B3The time, variable resistor R VThe resistance size equal resistance (R B1+ R B2+ R B3) the resistance size; The rest may be inferred; As decoded signal D X37For logical one to open switch SW B 37The time, variable resistor R VThe resistance size equal resistance (R B1+ R B2+ R B3+ ... + RB 37) the resistance size.
Resistance R XBe coupled between this output terminal and this second input end (negative input end) of operational amplifier OP; Gamma curve selector switch SW GBe coupled to equally between this output terminal and this second input end (negative input end) of operational amplifier OP.Gamma curve selector switch SW GSelect signal G according to gamma curve SWhether control will be with this output terminal of operational amplifier OP and this second input end (negative input end) short circuit together.If gamma curve selector switch SW GWith this output terminal and this second input end (negative input end) short circuit of operational amplifier OP, 400 of gamma voltage conversion apparatus then of the present invention can be to meet the gamma driving voltage V of gamma curve gamma A OUTOutput drives 3 volts liquid crystal panel; If gamma curve selector switch SW GWith this output terminal and this second input end (negative input end) short circuit of operational amplifier OP, 400 of gamma voltage conversion apparatus then of the present invention can be not meet the gamma driving voltage V of gamma curve gamma B OUTOutput drives 5 volts liquid crystal panel, the operation principles explanation as after.
Please continue with reference to figure 4.In Fig. 4, gamma voltage is adjusted circuit 420 can equivalence become a voltage conversion circuit 500 with operational amplifier OP.As gamma curve selector switch SW GSelection is during with this output terminal of operational amplifier OP and this second input end short circuit, and gamma voltage conversion apparatus 400 then of the present invention just can equivalence becomes the gamma voltage equivalent device 200 of prior art, with GTG signal D IN,, convert gamma driving voltage V to meet the mode of gamma curve gamma A OUTOutput is to drive 3 volts liquid crystal panel.And as gamma curve selector switch SW GWhen selecting not with this output terminal of operational amplifier OP and this second input end short circuit, the gamma driving voltage V that gamma voltage conversion apparatus 400 then of the present invention is exported OUT, just can produce according to following formula:
V OUT＝(R X/R V)×VIN 2…(1)
V IN2＝V IN1…(2)
V IN1＝V GA…(3)
V wherein IN2Be the voltage on this second input end (negative input end) of operational amplifier OP.And the gamma driving voltage V of this moment OUTCan be according to variable resistor R VThe resistance size adjust to meet gamma curve gammaB.And variable resistor R VResistance stool and urine according to GTG signal D INDecoded signal D after the decoding 01～D 064The decoded signal D that process code translator 4211 is deciphered once more X1～D X37Control, so just can guarantee via variable resistor R VAdjusted gamma driving voltage V OUTCan meet gamma curve gamma B, to drive 5 volts liquid crystal panel.
In addition, though it should be noted that GTG signal D INBe six bits, and therefore resistance serial 412 need 64 (2 6) individual resistance R A1～R A64Come GTG signal at each rank to carry out corresponding with gamma curve gamma A to produce corresponding gamma voltage V GAAnd in the resistance serial 4212 in the present invention, be to need the resistance of as much to connect in theory, yet at the GTG signal D of six bits INIn, the GTG signal on some rank, pairing variable resistor R VResistance, be identical, therefore, do not need resistance, switch and the decoded signal of as much number in resistance serial 4212 of the present invention and code translator 4211, just can finish GTG signal D with six bits INIn each rank GTG signal convert the gamma driving voltage V that meets gamma curve gamma B effectively to OUT, to drive 5 volts liquid crystal panel.
Please refer to Fig. 5.Fig. 5 is the synoptic diagram of an embodiment of explanation code translator 411 of the present invention.As shown in Figure 5, code translator 411 can be by 64 and door (AND gate) AND 1～AND 64And six phase inverter INV 1～INV 6 Implement.So code translator 411 just can be according to six bit (B 1, B 2, B 3, B 4, B 5, B 6) GTG signal D INCorrectly decipher out desired decoded signal D 01～D 064
Please refer to Fig. 6.Fig. 6 is the synoptic diagram of an embodiment of explanation code translator 4211 of the present invention.As shown in Figure 5, code translator 4211 can be implemented by a plurality of or door (OR gate).So code translator 4211 just can be according to decoded signal D 01～D 064Correctly decipher out desired decoded signal D X1～D X37
Please refer to Fig. 7,8,9.Fig. 7,8,9 is for illustrating the synoptic diagram of importing the operation principles of gamma voltage conversion apparatus 400 of the present invention when a GTG signal.In Fig. 7,8,9, set the GTG signal D of input INBe [000100].In Fig. 7, can find out at GTG signal D INDuring for [000100], 411 decoded signals of deciphering out according to this of code translator only have decoded signal D 05Be logical one.So in gamma voltage change-over circuit 410, switch SW A5Can be switched on, and with resistance serial 412 pairing electric resistance partial pressure V 5Output is with as gamma voltage V GA, and this first input end that is sent to operational amplifier OP is with as input voltage V IN1In Fig. 8, can find out is only having decoded signal D 05Under the situation for logical one, 4211 decoded signals of deciphering out according to this of code translator only have decoded signal D X5Be logical one.Therefore adjust in the circuit 420 switch SW at gamma voltage B5Can be switched on, and just be (R resistance serial 4212 pairing resistance B1+ R B2+ R B3+ R B4+ R B5) with as variable resistor R VResistance.Therefore, in Fig. 9, if gamma curve selector switch SW GSelection is during with this output terminal of operational amplifier OP and this second input end short circuit, and gamma voltage conversion apparatus 400 then of the present invention just can be exported size and be V 5Gamma driving voltage V OUT, and size is V 5Gamma driving voltage V OUTWith numerical value be the GTG signal D of [000100] INMeet gamma curve gamma A; Otherwise, if gamma curve selector switch SW GWhen selecting not with this output terminal of operational amplifier OP and this second input end short circuit, the gamma driving voltage V that gamma voltage conversion apparatus 400 then of the present invention is exported OUTJust can calculate according to formula (1), (2) and (3):
V IN1＝V GA＝V 5；
V IN2＝V IN1；
V OUT＝(R X/R V)×V IN2＝[R X/(R B1+R B2+R B3+R B4+R B5)]×V 5；
And according to gamma driving voltage V that following formula calculated OUTWith numerical value be the GTG signal D of [001000] INMeet gamma curve gamma B.
In sum, utilize gamma voltage conversion apparatus provided by the present invention, can be used to setting according to the user, select different gamma curve, to drive different liquid crystal panels, and do not need all to design corresponding gamma voltage conversion apparatus for every kind of liquid crystal panel, so just can reduce production costs and provide the user bigger convenience.
The above only is preferred embodiment of the present invention, and all equalizations of being done according to the present patent application claim change and modify, and all should belong to covering scope of the present invention.

Claims (7)

1. a gamma voltage conversion apparatus is used for according to a GTG signal, produces a corresponding gamma driving voltage, and this GTG signal and this gamma driving voltage meet one first gamma curve or one second gamma curve, and this gamma voltage conversion apparatus comprises:
One gamma voltage change-over circuit is used for producing one first gamma voltage according to this GTG signal, and this GTG signal and this first gamma voltage meet this first gamma curve;
One operational amplifier comprises:
One first input end is coupled to this gamma voltage change-over circuit, is used for receiving this first gamma voltage;
One second input end; And
One output terminal, this operational amplifier is according to this first input end of this operational amplifier and this second input end of this operational amplifier, export this first gamma voltage or one second gamma voltage with as this gamma driving voltage, this GTG signal and this second gamma voltage meet this second gamma curve; And
One gamma voltage is adjusted circuit, be coupled between this output terminal of this second input end of this operational amplifier and this operational amplifier, be used for selecting signal according to this a GTG signal and a gamma curve, control this operational amplifier and export this first gamma voltage or this second gamma voltage with as this gamma driving voltage
Wherein, this gamma voltage adjustment circuit comprises:
One first resistance has one first resistance, is coupled between this output terminal of this second input end of this operational amplifier and this operational amplifier;
One second switch is coupled between this output terminal of this second input end of this operational amplifier and this operational amplifier, is used for selecting signal according to this gamma curve, this second input end of this operational amplifier is coupled to this output terminal of this operational amplifier; And
One variable resistance circuit is coupled between this second input end and a ground end of this operational amplifier, is used for producing one second resistance according to this GTG signal;
Wherein the relation of this second gamma voltage and this first gamma voltage can be expressed from the next:
V G2=(1+R 1/ R 2) * V G1, V wherein G2Represent this second gamma voltage, V G1Represent this first gamma voltage, R 1Represent this first resistance, R 2Represent this second resistance.
2. gamma voltage conversion apparatus according to claim 1 is characterized in that, this gamma voltage change-over circuit comprises:
One first code translator is used for receiving this GTG signal to produce a plurality of first decoded signals according to this;
One first resistance serial is coupled between a reference voltage source and the ground end, comprises the resistance of a plurality of series connection, and each resistance of this first resistance serial has a predetermined resistance, and the electric resistance partial pressure of a correspondence is provided according to this reference voltage source;
A plurality of first switches, each first switch comprises:
One first end is coupled to a resistance corresponding in this first resistance serial, is used for receiving this electric resistance partial pressure of the corresponding correspondence that this resistance provided;
One second end is coupled to this first input end of this operational amplifier; And
One control end, be coupled to this first code translator, be used for receiving in these a plurality of first decoded signals one first corresponding decoded signal, this first switch couples this first switch according to this first decoded signal that is received this first end to this second end of this first switch to transmit this corresponding electric resistance partial pressure this first input end to this operational amplifier;
Wherein these a plurality of first switches this electric resistance partial pressure that is sent to this operational amplifier is promptly as this first gamma voltage.
3. gamma voltage conversion apparatus according to claim 2 is characterized in that, this first code translator can be implemented with door by a plurality of.
4. gamma voltage conversion apparatus according to claim 3 is characterized in that, a plurality of input ends with door in this first code translator are used for receiving this GTG signal; An output terminal with door in a plurality of and door in this first code translator is used for exporting one first corresponding decoded signal.
5. gamma voltage conversion apparatus according to claim 1 is characterized in that, this variable resistance circuit comprises:
One second resistance serial is coupled to this second input end of this operational amplifier, comprises the resistance of a plurality of series connection, and each resistance of this second resistance serial has a predetermined resistance;
One second code translator is coupled to this first code translator, is used for receiving these a plurality of first decoded signals to produce a plurality of second decoded signals;
A plurality of the 3rd switches, each the 3rd switch comprises:
One first end is coupled to a resistance corresponding in this second resistance serial;
One second end couples this ground end; And
One control end, be coupled to this second code translator, be used for receiving one second corresponding in these a plurality of second decoded signals decoded signal, the 3rd switch couples this first end to this second end of the 3rd switch of the 3rd switch and holds so that this corresponding in this second resistance serial resistance is coupled to this ground according to this second decoded signal that is received;
Wherein in these a plurality of the 3rd switches is coupled to this ground end with this corresponding in this second resistance serial resistance, and this second resistance serial is located at this summation that is coupled to the resistance of the preceding resistance of this resistance of holding on this ground and is this second resistance.
6. gamma voltage conversion apparatus according to claim 5 is characterized in that, this second code translator can be implemented by a plurality of or door.
7. gamma voltage conversion apparatus according to claim 6 is characterized in that, the input end a plurality of or door of this in this second code translator is coupled to the correspondence of this first code translator and the output terminal of door; In this second code translator this output terminal a plurality of or door is used for exporting one second corresponding decoded signal.
CN2008101757812A 2008-11-10 2008-11-10 Gamma voltage conversion apparatus Active CN101393730B (en)

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CN103021365B (en) * 2012-12-14 2015-01-21 京东方科技集团股份有限公司 Device and method for adjusting gamma curve and liquid crystal display device
KR102018125B1 (en) 2012-12-27 2019-09-04 엘지디스플레이 주식회사 Device of generating gamma voltage and a display device
CN103218968B (en) * 2013-04-27 2016-04-06 合肥京东方光电科技有限公司 Gamma resistance adjusting gear, driving circuit and display device
CN103366667B (en) * 2013-07-01 2016-03-30 北京京东方光电科技有限公司 Gamma voltage generation circuit and control method
CN104021771B (en) * 2014-06-17 2017-02-15 深圳市华星光电技术有限公司 Programmable gamma correction buffer circuit chip and method for generating gamma voltage
CN106384579B (en) * 2016-08-31 2019-03-12 深圳市华星光电技术有限公司 Gamma reference voltage generation circuit, liquid crystal display panel
CN106548760B (en) * 2017-01-16 2019-06-07 京东方科技集团股份有限公司 A kind of gamma voltage generation circuit and control method, source electrode driver
CN109787635A (en) 2019-01-10 2019-05-21 京东方科技集团股份有限公司 D/A converting circuit and its digital-analog convertion method, display device

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