CN115116377A - Voltage correction circuit and display device - Google Patents

Abstract

The invention discloses a voltage correction circuit and a display device. The voltage correction circuit includes: a correction module and a driving module connected in series between the output terminal and the control terminal of the power supply circuit; wherein, the correction module comprises: an amplification unit, a multiple correction unit and a signal correction unit; the multiple correction unit is connected to the amplifying unit. between the input end and the output end; the multiple correction unit is used to adjust the magnification of the amplifying unit; the signal correction unit is electrically connected to the input end of the amplifying unit; the signal correction unit is used to adjust the first adjustment signal transmitted to the input end of the amplifying unit; The amplifying unit is electrically connected with the driving module; the amplifying unit generates a correction signal in response to the first adjustment signal and the amplification factor, so that the driving module controls the output voltage of the power supply circuit. The embodiments of the present invention can improve the precision of the output voltage of the power supply circuit, thereby improving the display effect of the display device.

Description

Voltage correction circuit and display device

technical field

The present invention relates to the field of display technology, in particular to a voltage correction circuit and a display device.

Background technique

In the existing display device, the output voltage range of the power supply circuit in the driver chip is relatively wide. Due to the limitation of the voltage reference or bandwidth in the power supply loop, the output voltage of the power supply circuit has deviations, especially when the output voltage reaches the output voltage range. When it is near the maximum or minimum value, the precision deviation of the output voltage is large, which is likely to cause problems such as abnormal display screen.

SUMMARY OF THE INVENTION

The present invention provides a voltage correction circuit and a display device, so as to improve the precision of the output voltage of the power supply circuit, thereby improving the display effect of the display device.

To achieve the above technical purpose, the embodiments of the present invention provide the following technical solutions:

A voltage correction circuit, comprising: a correction module and a driving module connected in series between an output terminal and a control terminal of a power supply circuit;

Wherein, the correction module includes: an amplification unit, a multiple correction unit and a signal correction unit;

The multiple correction unit is connected between the input end and the output end of the amplifying unit; the multiple correction unit is used to adjust the magnification of the amplifying unit;

The signal correcting unit is electrically connected to the input end of the amplifying unit; the signal correcting unit is used to adjust the first adjustment signal transmitted to the input end of the amplifying unit;

The amplifying unit is electrically connected to the driving module; the amplifying unit generates a correction signal in response to the first adjustment signal and the amplification factor, so that the driving module controls the output voltage of the power supply circuit.

Optionally, the correction module further includes: a control unit, which is respectively electrically connected to the output end of the power supply circuit, the multiple correction unit and the signal correction unit; the control unit is configured to The output voltage of the power supply circuit controls the multiple correction unit to adjust the amplification factor of the amplifying unit, and controls the signal correction unit to adjust the first adjustment signal according to the output voltage of the power supply circuit.

Optionally, the multiple correction unit has an adjustable impedance; the multiple correction unit is configured to adjust the amplification factor of the amplifying unit by adjusting its impedance;

The signal correction unit has an adjustable impedance; the signal correction unit is used to adjust the first adjustment signal transmitted to the input end of the amplifying unit by adjusting its impedance.

Optionally, the output voltage of the power supply circuit is a positive value; when the output voltage of the power supply circuit exceeds a first threshold voltage, the impedance of the multiple correction unit is adjusted;

When the output voltage of the power supply circuit is lower than the second threshold voltage, adjusting the impedance of the signal correction unit;

Wherein, the first threshold voltage is greater than the second threshold voltage.

Optionally, the multiple correction unit includes: a first potentiometer; a first end of the first potentiometer is electrically connected to an input end of the amplifying unit, and a sliding end of the first potentiometer is connected to the amplifying unit The output terminal of the unit is electrically connected;

Preferably, the multiple correction unit further comprises: a first resistor; the first resistor and the first potentiometer are connected in series between the input end and the output end of the amplifying unit.

Optionally, the signal correction unit includes: a second potentiometer and a second resistor; the first end of the second potentiometer is connected to the first reference signal, and the second end of the second potentiometer is grounded, so The sliding end of the second potentiometer is electrically connected to the first end of the second resistor, and the second end of the second resistor is electrically connected to the input end of the amplifying unit.

Optionally, the amplifying unit includes: a first amplifier and a third resistor;

The first input terminal of the first amplifier is used as the input terminal of the amplifying unit, the second input terminal of the first amplifier is electrically connected to the first terminal of the third resistor, and the second input terminal of the third resistor is electrically connected. The terminal is grounded, and the output terminal of the first amplifier is used as the output terminal of the amplifying unit.

Optionally, the correction module further includes: a voltage dividing unit; the voltage correction circuit further includes: a sampling module;

The sampling module is electrically connected to the output end of the power supply circuit; the sampling module is used to collect the output voltage of the power supply circuit, and generate a sampling signal according to the output voltage;

The voltage dividing unit is respectively electrically connected to the input end of the amplifying unit and the sampling module; the voltage dividing unit is configured to generate a second adjustment signal according to the sampling signal; the amplifying unit responds to the first generating a correction signal after adjusting the signal, the amplification factor and the second adjusting signal;

Preferably, the voltage dividing unit includes: a fourth resistor; a first end of the fourth resistor is electrically connected to the sampling module, and a second end of the fourth resistor is electrically connected to the input end of the amplifying unit ;

Preferably, the sampling module includes: a fifth resistor and a sixth resistor; the first end of the fifth resistor is electrically connected to the output end of the power supply circuit; the second end of the fifth resistor is electrically connected to the output end of the power supply circuit; The first end of the six resistors is electrically connected and used as the output end of the sampling module; the second end of the sixth resistor is grounded;

Preferably, the sampling module further includes: an error amplifier; a first input end of the error amplifier is electrically connected to the second end of the fifth resistor, and a second end of the error amplifier is connected to a second reference signal, The output end of the error amplifier is used as the output end of the sampling module;

Preferably, the sampling module further comprises: a voltage follower; the input end of the voltage follower is electrically connected to the output end of the error amplifier, and the output end of the voltage follower serves as the output end of the sampling module.

Optionally, the driving module includes: a comparator; the power supply circuit includes: a power switching device;

The first input end of the comparator is electrically connected to the output end of the calibration module, the second input end of the comparator is connected to a triangular wave signal, and the output end of the comparator is connected to the control end of the power switch device electrical connection;

The control terminal of the power switch device is used as the control terminal of the power supply circuit, and the power switch device is used for controlling the output of the power supply circuit according to the signal of the control terminal.

Correspondingly, an embodiment of the present invention also provides a display device including a power supply circuit and a voltage correction circuit as provided in any embodiment of the present invention.

In the voltage correction circuit provided by the embodiment of the present invention, a correction module and a driving module are provided; the correction module includes an amplification unit, a multiple correction unit and a signal correction unit. Among them, the multiple correction unit adjusts the correction signal output by the correction module by adjusting the amplification factor of the amplifying unit. The multiple correction unit has strong adjustment ability and is more suitable for the output voltage of the power supply circuit with a large amplitude and/or output voltage. In the case of a large difference from its theoretical value, a relatively obvious adjustment effect can be provided to the correction signal through a small adjustment amount, so that the correction module can respond quickly according to the change of the output voltage. The signal correction unit adjusts the correction signal by adjusting the magnitude of the first adjustment signal. Compared with the multiple correction unit, the signal correction unit can realize finer adjustment of the correction signal, and the signal correction unit is more suitable for the output voltage with a smaller amplitude. And/or the output voltage has a small difference from its theoretical value, so as to realize the fine adjustment of the correction signal, avoid the overshoot of the correction signal caused by the large adjustment ability of the multiple correction unit, and ensure the stability of the adjustment. In the embodiment of the present invention, the correcting unit to be operated can be selected according to the output condition of the power supply circuit, or the function ratio of the two correcting units can be adjusted, so as to take into account the speed and accuracy of the output voltage adjustment of the power supply circuit. Therefore, compared with the prior art, the embodiments of the present invention can improve the accuracy of the output voltage of the power supply circuit, stabilize the power supply signal transmitted to the display device, and thereby improve the display effect of the display device.

It should be understood that the content described in this section is not intended to identify key or critical features of the embodiments of the invention, nor is it intended to limit the scope of the invention. Other features of the present invention will become readily understood from the following description.

Description of drawings

In order to illustrate the technical solutions in the embodiments of the present invention more clearly, the following briefly introduces the accompanying drawings used in the description of the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained from these drawings without creative effort.

1 is a schematic structural diagram of a voltage correction circuit provided by an embodiment of the present invention;

2 is a schematic structural diagram of another voltage correction circuit provided by an embodiment of the present invention;

3 is a schematic structural diagram of another voltage correction circuit provided by an embodiment of the present invention;

4 is a schematic structural diagram of another voltage correction circuit provided by an embodiment of the present invention;

FIG. 5 is a schematic structural diagram of another voltage correction circuit provided by an embodiment of the present invention.

Detailed ways

In order to make those skilled in the art better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only Embodiments are part of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

It should be noted that the terms "first", "second" and the like in the description and claims of the present invention and the above drawings are used to distinguish similar objects, and are not necessarily used to describe a specific sequence or sequence. It is to be understood that the data so used may be interchanged under appropriate circumstances such that the embodiments of the invention described herein can be practiced in sequences other than those illustrated or described herein. Furthermore, the terms "comprising" and "having", and any variations thereof, are intended to cover non-exclusive inclusion.

As described in the background art, in the existing display device, the output voltage of the power supply circuit in the driving chip has deviations. Taking the reference voltage signal for initializing the gate of the driving transistor and/or the anode of the light-emitting device in the pixel circuit as an example, its value is usually a negative value. In order to verify the output deviation of the power supply circuit, the inventors compared and calculated the deviation between the measured value and the theoretical value of the reference voltage signal in its entire output voltage range (eg -7.5-0V). The test results show that the measured value of the reference voltage signal has a certain deviation from the theoretical value in the entire output range, and the deviation is larger when the output voltage is near 0V and near -7.5V. Specifically, when the corresponding theoretical value exceeds -2.5V and is lower than -7.1V, the deviation between the measured value and the theoretical value of the output voltage of the power supply circuit exceeds 1%; and when the corresponding theoretical value is between -7.1 and -2.5V , the deviation between the measured value and the theoretical value of the output voltage of the power supply circuit is between 0.7% and 1%.

In addition, taking the pixel circuit in the display device composed of P-type transistors as an example, the voltage range of the high-level signal used to turn off the P-type transistor is usually 5-15V, the typical value is about 7V, and it may reach 10V in application, or even 12V. In the output voltage range of the high-level signal, the voltage deviation near the upper and lower limits of the voltage is large, and the voltage deviation in the middle part is small.

The above research shows that there is a deviation in the output voltage of the power supply circuit in the driver chip, especially when the output voltage is close to the upper and lower limit edges of the output voltage range, the deviation is particularly obvious, which will affect the display effect of the display device.

In order to solve the above problem, an embodiment of the present invention provides a voltage correction circuit, so as to realize the feedback adjustment of the output voltage of the power supply circuit. FIG. 1 is a schematic structural diagram of a voltage correction circuit provided by an embodiment of the present invention. Referring to FIG. 1 , the voltage correction circuit 100 includes: a correction module 20 and a driving module 30 connected in series between the output terminal and the control terminal of the power supply circuit 200 . The correction module 20 is used for generating a correction signal; the driving module 30 is used for controlling the output voltage Vo of the power supply circuit 200 according to the correction signal.

Specifically, the correction module 20 includes: an amplification unit 210 , a multiple correction unit 231 and a signal correction unit 232 . The multiplying correction unit 231 is connected between the input end and the output end of the amplifying unit 210 ; the multiplying correction unit 231 is used to adjust the multiplying factor of the amplifying unit 210 . The signal correcting unit 232 is electrically connected to the input terminal of the amplifying unit 210 ; the signal correcting unit 232 is used to adjust the first adjustment signal transmitted to the input terminal of the amplifying unit 210 . The amplifying unit 210 is electrically connected to the driving module 30 ; the amplifying unit 210 generates a correction signal in response to the first adjustment signal and the amplification factor, so that the driving module 30 controls the output voltage Vo of the power supply circuit 200 .

The output end of the amplifying unit 210 is used as the output end of the correction module 20 . The amplifying unit 210 is used for outputting a correction signal, and the output of the amplifying unit 210 is controlled by both the multiple correction unit 231 and the signal correction unit 232 . Specifically, for the adjustment of the magnification of the amplifying unit 210, a smaller adjustment amount can have a greater impact on the correction signal; for the adjustment of the input signal of the amplifying unit 210, a larger adjustment amount is required to have a greater effect on the correction signal Impact. Therefore, when the difference between the actual output voltage and the theoretical value is small, the signal correction unit 232 can adjust the first adjustment signal connected to the input end of the amplifying unit 210 to perform voltage correction; when the difference between the actual output voltage and the theoretical value is relatively large When , the voltage correction can be performed by adjusting the magnification of the amplifying unit 210 by the magnification correction unit 321 to balance the adjustment methods of the output voltage Vo in various deviation states, so that a small adjustment amount can be passed in each state. To achieve the required adjustment effect, and try to avoid the voltage overshoot caused by the adjustment of the magnification, so that the output voltage can achieve a linear change as much as possible.

In the voltage correction circuit 100 provided by the embodiment of the present invention, a correction module 20 and a driving module 30 are provided; the correction module 20 includes an amplification unit 210 , a multiple correction unit 231 and a signal correction unit 232 . The multiple correction unit 231 adjusts the correction signal output by the correction module 20 by adjusting the amplification factor of the amplifying unit 210. The multiple correction unit 231 has a strong adjustment ability, and is more suitable for the output voltage Vo of the power supply circuit 200. When the output voltage Vo differs greatly from its theoretical value, a smaller adjustment amount can be used to provide the correction signal with a more obvious adjustment effect, so that the correction module 20 can quickly respond to changes in the output voltage Vo. The signal correction unit 232 adjusts the correction signal by adjusting the magnitude of the first adjustment signal. Compared with the multiple correction unit 231, the signal correction unit 232 can realize more fine adjustment of the correction signal, and the signal correction unit 232 is more suitable for the output voltage Vo. When the amplitude is small, and/or the difference between the output voltage Vo and its theoretical value is small, fine adjustment of the correction signal can be achieved, avoiding overshoot of the correction signal caused by the large adjustment capability of the multiple correction unit 231, and ensuring the stability of the adjustment. In this embodiment of the present invention, the calibration unit to be operated may be selected according to the output condition of the power supply circuit 200 or the function ratio of the two calibration units may be adjusted, so as to take into account the speed and accuracy of the adjustment of the output voltage of the power supply circuit. Therefore, compared with the prior art, the embodiments of the present invention can improve the accuracy of the output voltage of the power supply circuit, stabilize the power supply signal transmitted to the display device, and thereby improve the display effect of the display device.

On the basis of the foregoing embodiments, optionally, the multiple correction unit 231 and the signal correction unit 232 both have adjustable impedances. The manner in which the two correction units realize adjustment and correction is as follows: the magnification correction unit 231 adjusts the magnification of the amplifying unit 210 by adjusting its own impedance. The signal correction unit 232 adjusts the first adjustment signal transmitted to the input terminal of the amplifying unit 210 by adjusting its own impedance.

FIG. 2 is a schematic structural diagram of another voltage correction circuit provided by an embodiment of the present invention. Referring to FIG. 2, on the basis of the above-mentioned embodiments, optionally, the correction module 20 further includes: a control unit 240, which is respectively electrically connected to the output end of the power supply circuit 200, the multiple correction unit 231 and the signal correction unit 232; The unit 240 is configured to control the multiplier correction unit 231 to adjust the amplification factor of the amplifying unit 210 according to the output voltage Vo of the power supply circuit 200 , and to adjust the first adjustment signal to the signal correction unit 232 according to the output voltage Vo of the power supply circuit 200 . Specifically, the control unit 240 adjusts the impedances of the multiple correction unit 231 and the signal correction unit 232 respectively according to the output voltage Vo. In this embodiment, setting the control unit 240 to directly adjust the impedance of the multiple correction unit 231 and the signal correction unit 232 according to the output signal Vo is equivalent to providing the control unit 240-multiple correction unit 231-amplification unit 210, and the control unit 240-signal The two correction branches of the correction unit 232 and the amplifying unit 210 for feedback adjustment of the correction signal according to the output signal Vo provide conditions for the real-time adjustment of the two correction units during the operation of the power supply circuit 200 .

Continuing to refer to FIG. 2 , on the basis of the foregoing embodiments, optionally, the calibration module 20 further includes a voltage dividing unit 220 ; the voltage calibration circuit 100 further includes the sampling module 10 . The sampling module 10 is electrically connected to the output end of the power supply circuit 200; the sampling module 10 is used for collecting the output voltage Vo of the power supply circuit 200, and generating a sampling signal according to the output voltage Vo. The voltage dividing unit 220 is respectively electrically connected to the input end of the amplifying unit 210 and the sampling module 10; the voltage dividing unit 210 is used for generating a second adjustment signal according to the sampling signal; the amplifying unit 210 is responsive to the first adjustment signal, the amplification factor and the second adjustment A correction signal is generated after the signal.

Setting in this way is equivalent to adding another correction branch to the voltage correction circuit 100 , that is, the feedback adjustment branch formed by the sampling module 10 - the voltage dividing unit 220 - the amplifying unit 210 is similar to the function of the first adjustment signal. The second adjustment signal output by the voltage dividing unit 220 also acts on the input end of the amplifying unit 210, so as to control the output of the amplifying unit 210 and realize a relatively fine adjustment of the correction signal. The correction branch cooperates with the correction branch formed by the above two correction units, so that the first adjustment signal, the amplification factor and the second adjustment signal act on the amplifying unit 210 at the same time, so as to realize the adjustment of the correction signal and increase the power supply correction. Flexibility and reliability of circuit 100 adjustment. The adjustment amount of the relevant parameters in the amplifying unit 210 by the voltage dividing unit 220 and the two correcting units can be adjusted according to the difference between the actual output voltage and the theoretical value, thereby realizing the precision adjustment of the output voltage Vo within the full voltage output range. Moreover, even if a certain correction branch fails, other correction branches can still perform feedback adjustment on the output voltage Vo, which can effectively ensure the reliability of the power supply correction circuit 100 .

Exemplarily, the voltage dividing unit 220 is an impedance unit, which can convert the sampling signal output by the sampling module 10 into a current signal and transmit it to the amplifying unit 210, and the second adjustment signal transmitted by the voltage dividing unit 220 to the input end of the amplifying unit 210 is denoted as I1. . In addition, the signal correction unit 232 can access the reference voltage signal, and through its impedance adjustment, the reference voltage signal can be converted into a current signal for transmission to the amplifying unit 210 , and the signal correction unit 232 can be transmitted to the first adjustment signal mark at the input end of the amplifying unit 210 . for I2. The impedance of the multiplier correction unit 231 is denoted as R01. Then, the current flowing through the multiple correction unit 231 is actually the sum of the second adjustment signal and the first adjustment signal, and the correction signal (denoted as Vc) output by the amplifying unit 210 is: Vc=R01*(I1+I2). It can be seen from this that when the impedance of the voltage dividing unit 220 is fixed, if the amplitude of the output voltage Vo is large, and/or the output voltage Vo is significantly different from its theoretical value, the impedance of the adjustment multiplier correction unit 231 can be adjusted and corrected. The signal Vc enables the correction module 20 to quickly respond to the change of the output voltage Vo, and achieve a more obvious adjustment effect of the correction signal Vc through a small impedance adjustment amount; if the amplitude of the output voltage Vo is small, and/or the output voltage Vo The difference from its theoretical value is small, and the correction signal Vc can be adjusted by adjusting the impedance of the signal correction unit 232 to achieve fine adjustment of the correction signal Vc and avoid overshoot of the correction signal Vc caused by the impedance change of the multiple correction unit 231 . In addition, the voltage dividing unit 220 can also be set as an impedance unit with adjustable impedance. In this way, by adjusting the impedance of the voltage dividing unit 220, the participation degree (adjustment ratio) of the adjustment branch where the voltage dividing unit 220 is located in the adjustment process can be adjusted. , to improve the flexibility of the adjustment process. The impedance adjustment of the voltage dividing unit 220 may also be implemented based on the output voltage Vo.

On the basis of the above embodiments, based on the output characteristics of the power supply circuit 200 and the adjustment characteristics of the correction module 20, optionally, the application modes of the voltage correction circuit 100 include but are not limited to the following:

In an embodiment, optionally, before the power supply circuit 200 is put into use, when the output voltage Vo corresponds to both ends of the theoretical output voltage range, at least one correction unit in the adjustment factor correction unit 231 and the signal correction unit 232 is firstly adjusted When the deviation of the output voltage Vo from the theoretical value in the entire output voltage range is within the allowable range, the adjustment is stopped, and the operating impedance of the multiple correction unit 231 and the signal correction unit 232 is determined. During the subsequent use of the power supply circuit 200 , the impedances of the multiple correction unit 231 and the signal correction unit 232 are kept unchanged as the above-mentioned operating impedance, and feedback adjustment is performed only through the correction branch where the voltage dividing unit 220 is located. In this way, the multiple correction unit 231 and the signal correction unit 232 only need to work before the power supply circuit 200 is put into use, and there is no need to repeat the adjustment during the use of the power supply circuit 200, which can simplify the control logic of the power supply circuit 200 and reduce the power supply. The operating power consumption of the circuit 200 .

In another embodiment, optionally, during the operation of the power supply circuit 200, the correction branch where the voltage dividing unit 220 is located may be controlled to work, and at least one of the multiple correction unit 231 and the signal correction unit 232 may be controlled to correct The correction branch where the unit is located works, so as to realize at least two feedback adjustments to the output voltage Vo, and improve the correction accuracy and the response speed of the correction circuit.

In yet another embodiment, optionally, when the output voltage Vo corresponds to the upper and lower limits of the theoretical output voltage range, multiple feedback adjustments in which all correction branches work can be used; and when the output voltage Vo corresponds to the theoretical output In the middle part of the voltage range, only the correction branch where the voltage dividing unit 220 is located is used for adjustment. In this way, it is equivalent to adopting multiple adjustments when the deviation between the output voltage Vo and the theoretical value is large, and using a correction branch to adjust when the deviation between the output voltage Vo and the theoretical value is small, so that the adjustment process conforms to the deviation of the output voltage Vo and the theoretical value. law.

To sum up, the voltage correction circuit 100 can optimize the first adjustment signal transmitted to the amplifying unit 210 and the amplification factor of the amplifying unit 210 on the basis of realizing the feedback adjustment of the output voltage Vo, so as to effectively increase the output voltage to the maximum value and the accuracy near the minimum value, so that the deviation of the output voltage Vo from the theoretical value in the full voltage range tends to be consistent, improving the accuracy and linearity of the output voltage Vo, and avoiding the problem of large voltage errors at both ends.

On the basis of the above embodiments, optionally, taking the output voltage Vo of the power supply circuit 200 as a positive value as an example; when the multiple correction unit 231 and the signal correction unit 232 are enabled, when the output voltage Vo exceeds the first threshold voltage , the control unit 240 adjusts the impedance of the multiplier correction unit 231 to adjust the magnification of the amplifying unit 210 so that the output voltage Vo reaches the theoretical value as soon as possible. When the output voltage Vo is lower than the second threshold voltage, the control unit 240 adjusts the impedance of the signal correction unit 232 to adjust the first adjustment signal transmitted to the input terminal of the amplifying unit 210 to avoid correction voltage overshoot caused by multiple adjustment. Wherein, the first threshold voltage is greater than the second threshold voltage.

The above-mentioned embodiments have been described by taking the example that the output voltage Vo is always a positive value, but this is not intended to limit the present invention. In other embodiments, if part or all of the theoretical output voltage range of the output voltage Vo is a negative voltage value, the adjustment and correction can be selected according to the relationship between the absolute value of the output voltage and the first threshold voltage and the second threshold voltage Signal correction unit.

Taking the activation of the multiple correction unit 231 and the signal correction unit 232 before the power supply circuit 200 is put into use as an example, specifically, the output voltage Vo is still used as a positive voltage for description. When the output voltage Vo corresponds to the upper limit of the theoretical output voltage, By adjusting the impedance of the multiple correction unit 231 so that the deviation between the current output voltage and the upper limit of the theoretical output voltage is within the allowable range, the impedance of the multiple correction unit 231 is fixed at the current impedance, and the output voltage Vo under the current impedance is tested within the full voltage range. Whether the deviation is within the allowable range; if the accuracy of the output voltage Vo near the theoretical voltage lower limit still does not meet the requirements, the output voltage Vo can be adjusted to a position corresponding to the theoretical output voltage lower limit, and the impedance of the signal correction unit 232 is adjusted to make The deviation between the current output voltage and the theoretical lower limit of the output voltage is within the allowable range, the impedance of the signal correction unit 232 is fixed at the current impedance, and it is tested whether the deviation of the output voltage Vo in the full voltage range under the current impedance is within the allowable range. Repeat the adjustment for many times until the deviation of the output voltage Vo in the entire voltage range is within the allowable range, then the operating impedances of the multiple correction unit 231 and the signal correction unit 232 can be determined.

The above embodiments exemplify the functional units and modules of the voltage correction circuit. The following describes specific structures that each functional unit and module may have, but does not limit the present invention.

FIG. 3 is a schematic structural diagram of another voltage correction circuit provided by an embodiment of the present invention. Referring to FIG. 3 , in an embodiment, optionally, the amplifying unit 210 includes: a first amplifier OP1 and a third resistor R3 ; the first input terminal (inverting input terminal) of the first amplifier OP1 is used as the Input terminal, the second input terminal (forward input terminal) of the first amplifier OP1 is electrically connected to the first terminal of the third resistor R3, the second terminal of the third resistor R3 is grounded, and the output terminal of the first amplifier OP1 is used as an amplifying unit 210 output.

Continuing to refer to FIG. 3 , on the basis of the foregoing embodiments, optionally, the voltage dividing unit 220 includes: a fourth resistor R4; a first end of the fourth resistor R4 is electrically connected to the sampling module 10; The two terminals are electrically connected to the input terminal of the amplifying unit 210 , that is, electrically connected to the first input terminal of the first amplifier OP1 . In this way, the sampling signal (voltage signal) generated after the sampling module 10 collects the output voltage Vo can be converted into the second adjustment signal (current signal) after passing through the fourth resistor R4.

Continuing to refer to FIG. 3 , on the basis of the foregoing embodiments, optionally, the multiple correction unit 231 includes: a first potentiometer W1; the first end of the first potentiometer W1 is electrically connected to the input end of the amplifying unit 210, and the first The sliding end of a potentiometer W1 is electrically connected to the output end of the amplifying unit 210 . Exemplarily, the first potentiometer W1 may be a digital potentiometer, which is connected to the correction circuit as a variable resistor. The control unit can control the number of resistors connected between the first end of the first potentiometer W1 and the sliding end by controlling the on-off of each analog switch inside the first potentiometer W1, thereby controlling the first potentiometer W1 to be connected to the amplifying unit 210. The impedance between the input terminal and the output terminal realizes the impedance adjustment of the multiple correction unit 231 .

Further, the multiple correction unit 231 may further include: a first resistor R1 ; the first resistor R1 and the first potentiometer W1 are connected in series between the input end and the output end of the amplifying unit 210 .

Continuing to refer to FIG. 3 , on the basis of the foregoing embodiments, optionally, the signal correction unit 232 includes: a second potentiometer W2 and a second resistor R2; the first end of the second potentiometer W2 is connected to the first reference signal Vref1, the second end of the second potentiometer W2 is grounded, the sliding end of the second potentiometer W1 is electrically connected to the first end of the second resistor R2, and the second end of the second resistor R2 is electrically connected to the input end of the amplifying unit 210 . Exemplarily, the second potentiometer W2 may be a digital potentiometer, which is connected to the correction circuit as a voltage dividing module. The control unit can control the number of resistors connected between the first end and the sliding end of the second potentiometer W2 by controlling the on-off of each analog switch in the second potentiometer W2, so as to realize the impedance adjustment of the multiple correction unit 231. In this way, the voltage value output by the sliding end of the second potentiometer W2 can be controlled, that is, the reference voltage value transmitted to the second resistor R2 can be controlled. to the input of the amplifying unit 210 .

FIG. 4 is a schematic structural diagram of another voltage correction circuit provided by an embodiment of the present invention. Referring to FIG. 4, in an embodiment, optionally, the sampling module 10 includes: a fifth resistor R5 and a sixth resistor R6, which constitute Resistor divider sampling circuit. The first end of the fifth resistor R5 is electrically connected to the output end of the power supply circuit 200; the second end of the fifth resistor R5 is electrically connected to the first end of the sixth resistor R6, and serves as the output end of the sampling module 10; the sixth resistor The second terminal of R6 is grounded.

Further, the sampling module 10 may further include: an error amplifier EA; the first input end (inverting input end) of the error amplifier EA is electrically connected to the second end of the fifth resistor R5, and the second end (forward direction) of the error amplifier EA is electrically connected The input terminal) is connected to the second reference signal Vref2, and the output terminal of the error amplifier EA is used as the output terminal of the sampling module 10. The value of the second reference signal Vref2 may be the theoretical value corresponding to the current output voltage Vo. By introducing the error amplifier EA, the deviation between the current output voltage Vo and the theoretical value can be obtained and amplified, so that the correction module 20 can obtain the deviation according to the current output voltage Vo. The amplified offset value generates a correction signal.

Further, the sampling module 10 further includes: a voltage follower 110 ; the input end of the voltage follower 110 is electrically connected to the output end of the error amplifier EA, and the output end of the voltage follower 110 serves as the output end of the sampling module 10 . The voltage follower 110 can be used as a buffer isolation device between the sampling module 10 and the calibration module 20 to ensure that the operations between the modules do not interfere with each other, and to improve the adjustment accuracy of the voltage calibration circuit. Specifically, the voltage follower 110 may include a second amplifier OP2 and a seventh resistor R7. The second input terminal (forward input terminal) of the second amplifier OP2 is electrically connected to the output terminal of the error amplifier EA, the output terminal of the second amplifier OP2 is electrically connected to the first terminal of the fourth resistor R4, and the seventh resistor R7 is connected to the Between the first input terminal (inverting input terminal) and the output terminal of the second amplifier OP2.

Based on the structure shown in Figure 4, the calculation formula of the correction signal Vc can be obtained:

Vc=-(W1+R1)[k(Vref2-Vfb)/R4+Vref1'/R2];

Among them, k(Vref2-Vfb)/R4 represents the second adjustment signal, k is the amplification factor of the error amplifier EA, Vfb is the feedback voltage output by the second end of the fifth resistor R5; Vref1'/R2 represents the first adjustment signal, Vref1' is the reference voltage transmitted to the second resistor R2 via the second potentiometer W2, its value is related to the characteristics of the second potentiometer W2 itself, the resistance between the first end and the wiper end of the second potentiometer W2, and the first The value of the reference signal Vref1 is related, ie Vref1'=f(Vref1, W2).

FIG. 5 is a schematic structural diagram of another voltage correction circuit provided by an embodiment of the present invention. Referring to FIG. 5, in an embodiment, optionally, the driving module 30 includes: a comparator CMP; the first input terminal (forward input terminal) of the comparator CMP is electrically connected to the output terminal of the calibration module 20, and the comparator The second input terminal (inverting input terminal) of the CMP is connected to the triangular wave signal Vramp, and the output terminal of the comparator CMP is electrically connected to the control terminal of the power supply circuit 200 . The driving module 30 can generate a PWM signal under the control of the correction signal and the triangular wave signal Vramp to control the operation of the power supply circuit 200 .

The power supply circuit 200 may include: a power switching device M1. The control terminal of the power switching device M1 serves as the control terminal of the power supply circuit 200 , and the power switching device M1 is used to control the output of the power supply circuit 200 according to the signal of the control terminal.

Exemplarily, the power supply circuit 200 further includes a power supply E, and the on-off of the power switching device M1 can determine whether the voltage of the power supply E can be transmitted to the output end of the power supply circuit 200 . Then, the driving process of the driving module 30 may be: when the correction signal is greater than the triangular wave signal Vramp, the comparator CMP outputs a high level, and controls the power switch device M1 to conduct, so that the voltage of the power supply E is transmitted to the output end of the power supply circuit 200 When the correction signal is less than the triangular wave signal Vramp, the comparator CMP outputs a low level, and controls the power switch device M1 to turn off, so that the voltage of the power supply E stops transmitting to the output end of the power supply circuit 200 . Accordingly, the voltage correction circuit can adjust the correction signal according to the output voltage Vo, and control the output signal of the comparator CMP according to the correction signal, so as to realize the feedback adjustment of the output voltage Vo.

Exemplarily, the power supply circuit 200 may have any topology including power switching devices, such as an LDO circuit, a Buck circuit, a Boost circuit, or a Buck-boost circuit, etc. The specific structure of the power supply circuit 200 is not limited herein. The output terminal of the driving module 30 can be connected to the control terminal of any power switch device in the power supply circuit 200 to realize the control of the output state of the power supply circuit 200 . The power switching device may be, for example, a MOS transistor, an IGBT, or a thyristor.

The embodiment of the present invention also provides a display device, which includes a power supply circuit and the voltage correction circuit provided by any embodiment of the present invention, and has corresponding beneficial effects. The display device may be any product or component with a display function, such as a mobile phone, a tablet computer, a TV, or a monitor. The power supply circuit may be a circuit structure including a power switching device, such as an LDO circuit, a Buck circuit, a Boost circuit, or a Buck-boost circuit. Exemplarily, a power supply circuit and a voltage correction circuit may be integrated in the driver chip in the display device; or, a power supply circuit may be provided in the driver chip, and the voltage correction circuit may be provided in other control chips. The specific structure may be set according to actual requirements. There are no restrictions. In addition, the driving chip is also used to provide data signals to the pixel circuit in the display device, so as to drive the light-emitting device in the pixel circuit to emit light.

The above-mentioned specific embodiments do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions may occur depending on design requirements and other factors. Any modifications, equivalent replacements and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims (10)

1. A voltage correction circuit, characterized in that, comprising: a correction module and a drive module connected in series between an output end and a control end of a power supply circuit; Wherein, the correction module includes: an amplification unit, a multiple correction unit and a signal correction unit; The multiple correction unit is connected between the input end and the output end of the amplifying unit; the multiple correction unit is used to adjust the magnification of the amplifying unit; The signal correcting unit is electrically connected to the input end of the amplifying unit; the signal correcting unit is used to adjust the first adjustment signal transmitted to the input end of the amplifying unit; The amplifying unit is electrically connected to the driving module; the amplifying unit generates a correction signal in response to the first adjustment signal and the amplification factor, so that the driving module controls the output voltage of the power supply circuit. 2 . The voltage correction circuit according to claim 1 , wherein the correction module further comprises: a control unit, which is electrically connected to the output end of the power supply circuit, the multiple correction unit and the signal correction unit respectively. 3 . connection; the control unit is configured to control the multiple correction unit to adjust the amplification factor of the amplifying unit according to the output voltage of the power supply circuit, and to control the signal correction unit to adjust the first amplification factor according to the output voltage of the power supply circuit A conditioning signal. 3 . The voltage correction circuit according to claim 1 , wherein the multiple correction unit has an adjustable impedance; the multiple correction unit is configured to adjust the amplification factor of the amplifying unit by adjusting its impedance; 3 . The signal correction unit has an adjustable impedance; the signal correction unit is used to adjust the first adjustment signal transmitted to the input end of the amplifying unit by adjusting its impedance. 4 . The voltage correction circuit according to claim 3 , wherein the output voltage of the power supply circuit is a positive value; when the output voltage of the power supply circuit exceeds a first threshold voltage, the voltage of the multiple correction unit is adjusted. 5 . impedance; When the output voltage of the power supply circuit is lower than the second threshold voltage, adjusting the impedance of the signal correction unit; Wherein, the first threshold voltage is greater than the second threshold voltage. 5. The voltage correction circuit according to claim 1 or 3, wherein the multiple correction unit comprises: a first potentiometer; the first end of the first potentiometer is electrically connected to the input end of the amplifying unit connected, the sliding end of the first potentiometer is electrically connected to the output end of the amplifying unit; Preferably, the multiple correction unit further comprises: a first resistor; the first resistor and the first potentiometer are connected in series between the input end and the output end of the amplifying unit. 6. The voltage correction circuit according to claim 1 or 3, wherein the signal correction unit comprises: a second potentiometer and a second resistor; the first end of the second potentiometer is connected to the first reference signal, the second end of the second potentiometer is grounded, the sliding end of the second potentiometer is electrically connected to the first end of the second resistor, and the second end of the second resistor is connected to the amplifying unit The input terminal is electrically connected. 7. The voltage correction circuit according to claim 1, wherein the amplifying unit comprises: a first amplifier and a third resistor; The first input terminal of the first amplifier is used as the input terminal of the amplifying unit, the second input terminal of the first amplifier is electrically connected to the first terminal of the third resistor, and the second input terminal of the third resistor is electrically connected. The terminal is grounded, and the output terminal of the first amplifier is used as the output terminal of the amplifying unit. 8. The voltage correction circuit according to claim 1, wherein the correction module further comprises: a voltage dividing unit; the voltage correction circuit further comprises: a sampling module; The sampling module is electrically connected to the output end of the power supply circuit; the sampling module is used to collect the output voltage of the power supply circuit, and generate a sampling signal according to the output voltage; The voltage dividing unit is respectively electrically connected to the input end of the amplifying unit and the sampling module; the voltage dividing unit is configured to generate a second adjustment signal according to the sampling signal; the amplifying unit responds to the first generating a correction signal after adjusting the signal, the amplification factor and the second adjusting signal; Preferably, the voltage dividing unit includes: a fourth resistor; a first end of the fourth resistor is electrically connected to the sampling module, and a second end of the fourth resistor is electrically connected to the input end of the amplifying unit ; Preferably, the sampling module includes: a fifth resistor and a sixth resistor; the first end of the fifth resistor is electrically connected to the output end of the power supply circuit; the second end of the fifth resistor is electrically connected to the output end of the power supply circuit; The first end of the six resistors is electrically connected and used as the output end of the sampling module; the second end of the sixth resistor is grounded; Preferably, the sampling module further includes: an error amplifier; a first input end of the error amplifier is electrically connected to the second end of the fifth resistor, and a second end of the error amplifier is connected to a second reference signal, The output end of the error amplifier is used as the output end of the sampling module; Preferably, the sampling module further comprises: a voltage follower; the input end of the voltage follower is electrically connected to the output end of the error amplifier, and the output end of the voltage follower serves as the output end of the sampling module. 9 . The voltage correction circuit according to claim 1 , wherein the driving module comprises: a comparator; the power supply circuit comprises: a power switching device; 10 . The first input end of the comparator is electrically connected to the output end of the calibration module, the second input end of the comparator is connected to the triangular wave signal, and the output end of the comparator is connected to the control end of the power switch device electrical connection; The control terminal of the power switch device is used as the control terminal of the power supply circuit, and the power switch device is used for controlling the output of the power supply circuit according to the signal of the control terminal. 10. A display device, characterized by comprising a power supply circuit and the voltage correction circuit according to any one of claims 1-9.

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