Patent Application
20250224439
This application is a Paris Convention, which claims the benefit of priority of Chinese Patent Application No. 202410046742.1 filed on Jan. 10, 2024. The contents of the above application is all incorporated by reference as if fully set forth herein in its entirety.
The present disclosure relates to the field of display technology, and in particular to a common voltage loading analog circuit and a display device.
Common voltage is used to provide a stable reference voltage for liquid crystals in a LCD panel. However, due to the coupling between data signals, a coupling capacitance is formed between the data signal line and the common voltage, resulting in a coupling effect, which may cause horizontal crosstalk in the LCD panel. Currently, a common voltage reference, that is, an operational amplifier (OP), is usually used for negative feedback compensation to reduce time and amplitude of coupling, so that horizontal crosstalk is mitigated. However, the electrical performance of operational amplifiers produced by different manufacturers with a same specification may be different, resulting in a difference in compensation capability, and a difference in degree of improvement in crosstalk of the LCD panel, and therefore the display effect of the LCD panel, in which operational amplifiers produced by different manufacturers with a same specification are adopted, is different.
In conjunction with
Therefore, it is necessary to provide a common voltage loading analog circuit to address this defect.
Embodiments of the present disclosure provide a common voltage loading analog circuit and a display device, which can avoid attenuation of a sine wave signal output by a signal generator during transmission, and test compensation capability of operational amplifiers by simulating a common voltage coupled in a display panel so as to filter out operational amplifiers having inconsistent compensation capability. Thereby, the consistency of the display effect of the liquid crystal display panel, in which operational amplifiers produced by different manufacturers with a same specification are adopted, is improved.
An embodiment of the present disclosure provides a common voltage loading analog circuit configured for testing compensation capability of an operational amplifier to be tested. The common voltage loading analog circuit includes:
An embodiment of the present disclosure further provides a display device including the common voltage loading analog circuit as described above.
Beneficial effects of the embodiments of the present disclosure are as follows. The embodiments of the present disclosure provide a common voltage loading analog circuit and a display device, wherein the common voltage loading analog circuit is configured for testing compensation capability of operational amplifiers to be tested. The common voltage loading analog circuit includes a circuit unit to be tested, a load simulation circuit unit, and an auxiliary circuit unit. The load simulation circuit unit includes a signal generator, an amplifier circuit, and a resistance-capacitor series circuit. The signal generator is electrically connected to an input terminal of the amplifier circuit, and an output terminal of the amplifier circuit is electrically connected to an input terminal of the resistance-capacitor series circuit. A first output terminal of the resistance-capacitor series circuit is electrically connected to an input terminal of the circuit unit to be tested, and a second output terminal of the resistance-capacitor series circuit is electrically connected to an output terminal of the circuit unit to be tested. Through the resistance-capacitor series circuit, an AC component in the output voltage of the load simulation circuit unit can be completely filtered out to the input terminal of the circuit unit to be tested, and in combination with a DC component output from the auxiliary circuit unit to the input terminal of the circuit unit to be tested, the voltage at the input terminal of the circuit unit to be tested is consistent with the output voltage of the load simulation circuit unit, without attenuation. Therefore, the accuracy of measuring the compensation effect of the operational amplifiers to be tested is improved, the selection of operational amplifiers with consistent compensation capability is facilitated, and the horizontal crosstalk compensation effect of the liquid crystal display panel, in which operational amplifiers produced by different manufacturers with a same specification are adopted, is consistent. Thereby, the consistency of the display effect of the liquid crystal display panel, in which operational amplifiers produced by different manufacturers with a same specification are adopted, is improved.
The following description of the embodiments refers to the accompanying drawings to illustrate specific embodiments which the present disclosure may implement. The directional terms mentioned in the present disclosure, such as “upper”, “lower”, “front”, “back”, “left”, “right”, “inner”, “outer”, “side”, etc. only refer to the direction of the pictures in the drawings. Therefore, the directional terms used are intended to explain and understand the present disclosure, rather than to limit the present disclosure. In the figures, units with similar structures are represented by the same reference numbers.
The present disclosure will be further described below with reference to the accompanying drawings and specific embodiments of the invention.
Embodiments of the present disclosure provide a common voltage loading analog circuit, which can avoid the attenuation of the sine wave signal output by the signal generator during the transmission process, and test compensation capability of operational amplifiers by simulating a common voltage coupled in a display panel so as to filter out operational amplifiers having inconsistent compensation capability. Thereby, the consistency of the display effect of the liquid crystal display panel, in which operational amplifiers produced by different manufacturers with a same specification are adopted, is improved.
Referring to
It is to be noted that the common voltage loading analog circuit provided by the embodiments of the present disclosure is configured for testing the compensation effect of the operational amplifier to be tested U3. The common voltage loading analog circuit itself does not include the operational amplifier to be tested U3. In practical applications, the operational amplifier to be tested U3 can be any type of operational amplifier, and the operational amplifier to be tested U3 is electrically connected to the circuit unit to be tested 1, the load simulation circuit unit 2, and the auxiliary circuit unit 3 using the connection method shown in
The load simulation circuit unit 2 is configured for simulating a coupled common voltage. The load simulation circuit unit 2 includes a signal generator XFG1, an amplifier circuit and a resistance-capacitor series circuit. The signal generator XFG1 is electrically connected to an input terminal of the amplifier circuit, and an output terminal of the amplifier circuit is electrically connected to an input terminal of the resistance-capacitor series circuit. A first output terminal of the resistance-capacitor series circuit is electrically connected to an input terminal of the circuit unit to be tested 1, and a second output terminal of the resistance-capacitor series circuit is electrically connected to an output terminal of the circuit unit to be tested 1.
The auxiliary circuit unit 3 is configured for providing a positive input voltage to a positive input terminal of the operational amplifier to be tested U3. An output terminal of the auxiliary circuit unit 3 is electrically connected to the positive input terminal of the operational amplifier to be tested U3. The output terminal of the auxiliary circuit unit 3 is also electrically connected to the input terminal of the circuit unit to be tested 1.
In this embodiment, a sine wave generated by the signal generator XFG1 is provided to the amplifier circuit to simulate a coupled in-plane common voltage by changing an input frequency or amplitude of the signal generator XFG1. Through the resistance-capacitor series circuit, an AC component in the output voltage of the load simulation circuit unit 2 can be completely filtered out to the input terminal of the circuit unit to be tested 1, and in combination with a DC component output from the auxiliary circuit unit 3 to the input terminal of the circuit unit to be tested 1, the voltage at the input terminal of the circuit unit to be tested 1 is consistent with the output voltage of the load simulation circuit unit 2, without attenuation. Therefore, the accuracy of measuring the compensation effect of the operational amplifiers to be tested U3 is improved, the selection of operational amplifiers with consistent compensation capability is facilitated, and the horizontal crosstalk compensation effect of the liquid crystal display panel, in which operational amplifiers produced by different manufacturers with a same specification are adopted, is consistent. Thereby, the consistency of the display effect of the liquid crystal display panel, in which operational amplifiers produced by different manufacturers with a same specification are adopted, is improved.
In some embodiments, the amplifier circuit includes a first operational amplifier U1, a first resistance R1 and a second resistance R2. A positive input terminal of the first operational amplifier U1 is electrically connected to a positive terminal of the signal generator XFG1. A first terminal of the first resistance R1 is electrically connected to a first terminal of the second resistance R2 and an inversed input terminal of the first operational amplifier U1. A second terminal of the first resistance R1 and a common terminal of the signal generator XFG1 are both grounded. A second terminal of the second resistance R2 and an output terminal of the first operational amplifier U1 are both electrically connected to the input terminal of the resistance-capacitor series circuit.
In one embodiment, the resistance-capacitor series circuit includes a first capacitor C1, a second capacitor C2, a third capacitor C3, a fourth capacitor C4, a third resistance R3, a fourth resistance R4, and a fifth resistance R5. First terminals of the first capacitor C1, of the second capacitor C2, of the third capacitor C3, and of the fourth capacitor C4 are all electrically connected to the output terminal of the first operational amplifier U1. A second terminal of the first capacitor C1 is connected with the third resistance R3, the fourth resistance R4, and the fifth resistance R5 sequentially in series. The second terminal of the second capacitor C2 along with the third resistance R3 and the fourth resistance R4 are electrically connected to the output terminal of the circuit unit to be tested 1. A second terminal of the third capacitor C3 is electrically connected to a series common point between the fourth resistance R4 and the fifth resistance R5, and a second terminal of the fourth capacitor C4 along with the fifth resistance R5 are electrically connected to the input terminal of the circuit unit to be tested 1.
In some embodiments, the auxiliary circuit unit 3 includes a second operational amplifier U2 and a seventh resistance R7. A positive input terminal of the second operational amplifier U2 is input with a DC high-voltage signal. An inversed input terminal and an output terminal of the second operational amplifier U2 are electrically connected to a first terminal of the seventh resistance R7, and a second terminal of the seventh resistance R7 is electrically connected to the positive input terminal of the operational amplifier to be tested U3.
Negative power terminals of both the first operational amplifier U1 and the second operational amplifier U2 are connected to a DC low-voltage signal. A maximum value of the DC low-voltage signal is greater than a maximum value of an input voltage of the operational amplifier to be tested U3. A minimum value of the DC low-voltage signal is smaller than the minimum value of an input voltage of the operational amplifier to be tested U3. An input voltage of the operational amplifier to be tested U3 is the difference between a positive input voltage and an inversed input voltage of the operational amplifier to be tested U3. That means, the ranges of the DC voltage signals of both the first operational amplifier U1 and the second operational amplifier U2 are greater than the range of the input voltage of the operational amplifier to be tested U3.
In one embodiment, the first operational amplifier U1, the second operational amplifier U2, and the operational amplifier to be tested U3 are of a same model. The models of the first operational amplifier U1, of the second operational amplifier U2, and of the operational amplifier to be tested U3 are all OPA604AP. In practical applications, the models of the first operational amplifier U1, of the second operational amplifier U2, and of the operational amplifier to be tested U3 can be selected according to actual needs, rather than being limited to the above models.
In some embodiments, the common voltage loading analog circuit further includes a fifth capacitor C5. A first terminal of the fifth capacitor C5 and the second terminal of the seventh resistance R7 are electrically connected to the positive input terminal of the operational amplifier to be tested U3. A second terminal of the fifth capacitor C5 is grounded.
In some embodiments, the common voltage loading analog circuit further includes a sixth resistance R6. A first terminal of the sixth resistance R6 is electrically connected to the input terminal of the circuit unit to be tested 1. A second terminal of the sixth resistance R6 is electrically connected to the positive input terminal of the operational amplifier to be tested U3.
In some embodiments, the circuit unit to be tested 1 includes an eighth resistance R8, a ninth resistance R9, a tenth resistance R10, and a sixth capacitor C6. A first terminal of the eighth resistance R8 is electrically connected to both a first terminal of the tenth resistance R10 and the output terminal of the operational amplifier to be tested U3. A second terminal of the eighth resistance R8 is electrically connected to the second output terminal of the resistance-capacitor series circuit. The second output terminal of the resistance-capacitor series circuit is a series common point between the third resistance R3 and the fourth resistance R4. That means, the second terminal of the eighth resistance R8 is electrically connected to the series common point between the third resistance R3 and the fourth resistance R4. A first terminal of the ninth resistance R9 is electrically connected to a second terminal of the tenth resistance R10 and an inversed input terminal of the operational amplifier to be tested U3. A second terminal of the ninth resistance R9 is electrically connected to a first terminal of the sixth capacitor C6. A second terminal of the sixth capacitor C6 is electrically connected to the first output terminal of the resistance-capacitor series circuit. The first output terminal of the resistance-capacitor series circuit is a series common point between the sixth resistance R6 and the fifth resistance R5. That means, the second terminal of the sixth capacitor C6 is electrically connected to the series common point between the sixth resistance R6 and the fifth resistance R5.
In one embodiment, as shown in
The resistance values of the first resistance R1 and the second resistance R2 are both 1 kΩ. The resistance values of the third resistance R3, the fourth resistance R4, the fifth resistance R5, the sixth resistance R6, the seventh resistance R7 and the eighth resistance R8 are all 10Ω. The resistance value of the ninth resistance R9 is 1 kΩ. The resistance value of the tenth resistance R10 is 2 kΩ. The capacitances of the first capacitor C1, the second capacitor C2, the third capacitor C3, the fourth capacitor C4 and the fifth capacitor C5 are all 10 nF, and the capacitance of the sixth capacitor C6 is 0.1 μF. In practical applications, the resistance values of each resistance and the capacitance of each capacitor can be set according to actual needs, rather than being limited to the numerical values in the above embodiments.
By the resistance-capacitor series circuit, the AC component in the signal output by the output terminal of the first operational amplifier U1 can be completely filtered out to the first node C shown in
As shown in
By adjusting the ratio of the first resistance R1 to the second resistance R2, the frequency and amplitude of the input voltage of the load simulation circuit unit 2 can be adjusted, thereby changing the frequency and amplitude of the output voltage of the load simulation circuit unit 2, and thereby changing the frequency and amplitude of the inversed input voltage of the operational amplifier to be tested U3. Since the positive input voltage of the operational amplifier to be tested U3 remains unchanged, the difference of the positive input voltage (Vin+) and the inversed input voltage (Vin−) of the operational amplifier to be tested increases. Due to the principle of negative feedback amplification, the output voltage of the circuit unit to be tested 1 varies inversely with the difference between the positive input voltage (Vin+) and the negative input voltage (Vin−), and thus, the output current of the circuit unit to be tested 1 is changed.
For example, the output voltage amplitude of the load simulation circuit unit 2 increases. In order to maintain the stability of the output voltage of the circuit unit to be tested 1, it is necessary to reduce the output voltage of the circuit unit to be tested 1. At this time, the current will increase, while the output current of the circuit unit to be tested 1 can be controlled by reducing the voltage amplitude of the load simulation circuit unit 2.
The compensation capability of the operational amplifier to be tested U3 can be judged by testing the amplitude of the output current at the output terminal of the circuit unit to be tested 1 (i.e., the third node E) and the “timeliness” of compensation.
In addition to the common voltage loading analog circuit provided in the above embodiments of the present disclosure, another embodiment of the present disclosure provides a display device, which includes the common voltage loading analog circuit provided in any of the above embodiments.
Beneficial effects of the embodiments of the present disclosure are as follows. The embodiments of the present disclosure provide a common voltage loading analog circuit, the common voltage loading analog circuit is configured for testing compensation capability of operational amplifiers to be tested. The common voltage loading analog circuit includes a circuit unit to be tested, a load simulation circuit unit, and an auxiliary circuit unit. The load simulation circuit unit includes a signal generator, an amplifier circuit, and a resistance-capacitor series circuit. The signal generator is electrically connected to an input terminal of the amplifier circuit, and an output terminal of the amplifier circuit is electrically connected to an input terminal of the resistance-capacitor series circuit. A first output terminal of the resistance-capacitor series circuit is electrically connected to an input terminal of the circuit unit to be tested, and a second output terminal of the resistance-capacitor series circuit is electrically connected to an output terminal of the circuit unit to be tested. Through the resistance-capacitor series circuit, an AC component in the output voltage of the load simulation circuit unit can be completely filtered out to the input terminal of the circuit unit to be tested, and in combination with a DC component output from the auxiliary circuit unit to the input terminal of the circuit unit to be tested, the voltage at the input terminal of the circuit unit to be tested is consistent with the output voltage of the load simulation circuit unit, without attenuation. Therefore, the accuracy of measuring the compensation effect of the operational amplifiers to be tested is improved, the selection of operational amplifiers with consistent compensation capability is facilitated, and the horizontal crosstalk compensation effect of the liquid crystal display panel, in which operational amplifiers produced by different manufacturers with a same specification are adopted, is consistent. Thereby, the consistency of the display effect of the liquid crystal display panel, in which operational amplifiers produced by different manufacturers with a same specification are adopted, is improved.
In summary, although the present disclosure has been stated as above with preferred embodiments, the above preferred embodiments are not intended to limit the present disclosure. A person skilled in the art may make various modifications and refinements without departing from the spirit and scope of the present disclosure, and therefore the scope of protection of the present disclosure shall be based on the scope defined by the claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202410046742.1 | Jan 2024 | CN | national |
