Drive Circuit, Chip, and Display Device

Abstract

The present invention discloses a driving circuit, a chip, and a display device. The driving circuit includes: a first driving unit configured to output a first driving signal for driving one of a first display unit or a second display unit, and a first power supply terminal of the first driving unit is connected to a first power supply voltage; a second driving unit configured to output a second driving signal for driving the other of the first display unit or the second display unit; a first power supply unit, an output terminal of the first power supply unit is coupled to a second power supply terminal of the first driving unit, the second power supply terminal of the first driving unit is coupled to a first power supply terminal of the second driving unit, the first power supply unit is configured to provide a first regulating current, a second power supply terminal of the second driving unit is connected to a second power supply voltage, and the first power supply voltage is greater than the second power supply voltage. Through the technical solution of the present invention, the power consumption of the driving circuit can be reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of circuits, and in particular, to a driving circuit, a chip, and a display device. Background Art

[0002] Driving circuits are widely used in products such as liquid crystal display screens. For example, a driving circuit can charge the liquid crystal capacitors in a liquid crystal display screen to required gray-scale voltages to adjust the brightness values of different pixel points, so that the liquid crystal display screen can display required images. The driving circuit includes a plurality of paired driving units, and the driving units need to work under specific operating voltages.

[0003] In the prior art, when the common electrode of a liquid crystal panel is grounded, to prevent the liquid crystal panel from flickering due to the DC deviation of the liquid crystal capacitors, the common practice is to set the positive and negative gray-scale voltages asymmetrically. To match the asymmetric gray-scale voltages, the above-mentioned paired driving units require asymmetric supply voltages.

[0004] However, the power consumption of the driving circuit in the prior art is too large. Summary of the Invention

[0005] The technical problem solved by the present invention is how to design the structure of a driving circuit to reduce the power consumption of the driving circuit.

[0006] To solve the above technical problem, the present invention provides a driving circuit, which includes: a first driving unit for outputting a first driving signal for driving one of a first display unit and a second display unit, and a first power supply terminal of the first driving unit is connected to a first power supply voltage; a second driving unit for outputting a second driving signal for driving the other of the first display unit and the second display unit; a first power supply unit, an output terminal of the first power supply unit is coupled to a second power supply terminal of the first driving unit, the second power supply terminal of the first driving unit is coupled to a first power supply terminal of the second driving unit, the first power supply unit is used to provide a first adjustment current, a second power supply terminal of the second driving unit is connected to a second power supply voltage, and the first power supply voltage is greater than the second power supply voltage.

[0007] Optionally, when the current value of the output current at the second power supply terminal of the first driving unit is less than a first target current, the current value of the first adjustment current is the difference between the first target current and the current value of the output current at the second power supply terminal of the first driving unit; when the current value of the output current at the second power supply terminal of the first driving unit is equal to the first target current, the first adjustment current is zero; the first target current is the current required at the first power supply terminal of the second driving unit when the second driving unit operates normally.

[0008] Optionally, when the current value of the output current of the second power supply terminal of the first driving unit is greater than the first target current, the first regulated current is negative, and a part of the output current of the second power supply terminal of the first driving unit flows into the first power supply unit, and the current value of the part of the current is the difference between the current value of the output current of the second power supply terminal of the first driving unit and the first target current.

[0009] Optionally, the first power supply unit is further configured to reduce the part of the current to zero.

[0010] Optionally, the first power supply unit is further configured to provide a third power supply voltage, where the third power supply voltage is less than or equal to the first target voltage of the second power supply terminal of the first driving unit, and the first target voltage is the maximum value of the power supply voltage required by the second power supply terminal of the first driving unit when the first driving unit is in an operating state; the third power supply voltage is greater than or equal to the second target voltage of the first power supply terminal of the second driving unit, and the second target voltage is the minimum value of the power supply voltage required by the first power supply terminal of the second driving unit when the second driving unit is in an operating state.

[0011] Optionally, the first power supply unit includes a low dropout linear regulator, the low dropout linear regulator includes a MOS transistor, the MOS transistor is configured to output the first regulated current and the third power supply voltage, and the on-resistance of the MOS transistor is configured as the resistance value corresponding to the third power supply voltage and the first regulated current.

[0012] Optionally, the driving circuit further includes: a first gamma voltage unit configured to provide a first gamma voltage, the first gamma voltage being used to generate the first driving signal, and a first power supply terminal of the first gamma voltage unit is connected to the first power supply voltage; a second gamma voltage unit configured to provide a second gamma voltage, the second gamma voltage being used to generate the second driving signal, and a second power supply terminal of the second gamma voltage unit is connected to the second power supply voltage; a second power supply unit, an output terminal of the second power supply unit is coupled to a second power supply terminal of the first gamma voltage unit, the second power supply terminal of the first gamma voltage unit is coupled to a first power supply terminal of the second gamma voltage unit, and the first power supply unit is configured to provide a second regulated current, where the current value of the second regulated current is the difference or zero between the second target current and the current value of the output current of the second power supply terminal of the first gamma voltage unit, and the second target current is configured as the current value of the current flowing into the first power supply terminal of the second gamma voltage unit.

[0013] Optionally, the driving circuit further includes: a first digital-to-analog conversion unit, the first digital-to-analog conversion unit is coupled between the first driving unit and the first gamma voltage unit, the first digital-to-analog conversion unit is configured to convert the first gamma voltage into a first control signal corresponding to a first target gray value, the first control signal is used to generate the first driving signal, and a first power supply terminal of the first digital-to-analog conversion unit is connected to the first power supply voltage; a second digital-to-analog conversion unit, the second digital-to-analog conversion unit is coupled between the second driving unit and the second gamma voltage unit, and is configured to convert the second gamma voltage into a second control signal corresponding to a second target gray value, the second control signal is used to generate the second driving signal, and a second power supply terminal of the second digital-to-analog conversion unit is connected to the second power supply voltage; a third power supply unit, an output terminal of the third power supply unit is coupled to a second power supply terminal of the first digital-to-analog conversion unit, the second power supply terminal of the first digital-to-analog conversion unit is coupled to a first power supply terminal of the second digital-to-analog conversion unit, and the third power supply unit is configured to provide a third adjustment current, wherein a current value of the third adjustment current is a difference or zero between a third target current and a current value of an output current of the second power supply terminal of the first digital-to-analog conversion unit, and the third target current is configured to be a current value of a current flowing into the first power supply terminal of the second digital-to-analog conversion unit.

[0014] Optionally, the first driving unit includes a first operational amplifier, a positive input terminal of the first operational amplifier is connected to the first control signal, and a negative input terminal of the first operational amplifier is coupled to an output terminal of the first operational amplifier; the second driving unit includes a second operational amplifier, a positive input terminal of the second operational amplifier is connected to the second control signal, and a negative input terminal of the second operational amplifier is coupled to an output terminal of the second operational amplifier.

[0015] Optionally, the driving circuit further includes a switching unit, a first input terminal of the switching unit is connected to the first driving signal, a second input terminal of the switching unit is connected to the second driving signal, and the switching unit is configured to input the first driving signal into the first display unit and input the second driving signal into the second display unit, or input the first driving signal into the second display unit and input the second driving signal into the first display unit.

[0016] Optionally, the first display unit and the second display unit include liquid crystal capacitors.

[0017] The present invention also discloses a chip including the driving circuit.

[0018] The present invention also discloses a display device including a plurality of display units and the driving circuit.

[0019] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0020] The present invention provides a driving circuit, which includes a first driving unit, a second driving unit, and a first power supply unit. The first driving unit is configured to output a first driving signal for driving one of a first display unit or a second display unit, and a first power supply terminal of the first driving unit is connected to a first power supply voltage. The second driving unit is configured to output a second driving signal for driving the other one of the first display unit or the second display unit in the display unit. An output terminal of the first power supply unit is coupled to a second power supply terminal of the first driving unit, and the second power supply terminal of the first driving unit is coupled to a first power supply terminal of the second driving unit. The first power supply unit is configured to provide a first regulation current, a second power supply terminal of the second driving unit is connected to a second power supply voltage, and the first power supply voltage is greater than the second power supply voltage. By coupling the output terminal of the first power supply unit to the second power supply terminal of the first driving unit and coupling the second power supply terminal of the first driving unit to the first power supply terminal of the second driving unit, the technical solution of the present invention can reuse the output current of the second power supply terminal of the first driving unit and transmit the output current of the second power supply terminal of the first driving unit to the first power supply terminal of the second driving unit, compared with only providing the working current required for the first power supply terminal of the second driving unit by the first power supply unit, thereby reducing the first regulation current that the first power supply unit needs to provide, further greatly reducing the power consumption of the first power supply unit and reducing the power consumption of the driving circuit.

[0021] Further, when the current value of the output current of the second power supply terminal of the first driving unit is greater than a first target current, a part of the output current of the second power supply terminal flows into the first power supply unit, and the first power supply unit can reduce the part of the current to zero. The present invention can set the output current of the second power supply terminal of the first driving unit and the first target current so that the output current of the second power supply terminal of the first driving unit is greater than or equal to the first target current, thereby enabling the first power supply current not to provide the first regulation current and further reducing the power consumption of the driving circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a schematic structural diagram of a driving circuit in the prior art;

[0023] Figure 2 is a schematic structural diagram of a driving circuit provided by an embodiment of the present invention;

[0024] Figure 3 is a specific schematic structural diagram of a driving circuit provided by an embodiment of the present invention;

[0025] Figure 4 is a specific schematic structural diagram of a first power supply unit provided by an embodiment of the present invention;

[0026] Figure 5 It is a schematic structural diagram of another driving circuit provided by an embodiment of the present invention;

[0027] Figure 6 It is a schematic structural diagram of a driving circuit in a specific application scenario provided by an embodiment of the present invention;

[0028] Figure 7 It is a timing diagram of a driving circuit provided by an embodiment of the present invention. Detailed implementation manners

[0029] As described in the background art, when adjusting the power supply voltage in the prior art, the provided power supply voltage is usually adjusted according to the deviation voltage of the driving unit so that the power supply voltage range meets the working requirements of the driving unit. However, the power consumption of the driving circuit in the prior art is too large.

[0030] The present invention provides a driving circuit, which includes a first driving unit, a second driving unit and a first power supply unit. The first driving unit is configured to output a first driving signal for driving one of a first display unit or a second display unit, and a first power supply terminal of the first driving unit is connected to a first power supply voltage; the second driving unit is configured to output a second driving signal for driving the other of the first display unit or the second display unit in the display unit; an output terminal of the first power supply unit is coupled to a second power supply terminal of the first driving unit, the second power supply terminal of the first driving unit is coupled to a first power supply terminal of the second driving unit, the first power supply unit is configured to provide a first regulation current, a second power supply terminal of the second driving unit is connected to a second power supply voltage, and the first power supply voltage is greater than the second power supply voltage. The technical solution of the present invention couples the output terminal of the first power supply unit to the second power supply terminal of the first driving unit, and couples the second power supply terminal of the first driving unit to the first power supply terminal of the second driving unit. Compared with only providing the working current required for the first power supply terminal of the second driving unit by the first power supply unit, the present invention can reuse the output current of the second power supply terminal of the first driving unit, transmit the output current of the second power supply terminal of the first driving unit to the first power supply terminal of the second driving unit, thereby reducing the first regulation current that the first power supply unit needs to provide, and further greatly reducing the power consumption of the first power supply unit and reducing the power consumption of the driving circuit.

[0031] Further, when the current value of the output current of the second power supply terminal of the first driving unit is greater than the first target current, a part of the output current of the second power supply terminal flows into the first power supply unit, and the first power supply unit can reduce the part of the current to zero. The present invention can set the output current of the second power supply terminal of the first driving unit and the first target current so that the output current of the second power supply terminal of the first driving unit is greater than or equal to the first target current, so that the first power supply current does not need to provide the first adjustment current, further reducing the power consumption of the driving circuit.

[0032] Figure 1 It is a partial structural schematic diagram of a driving circuit in the prior art.

[0033] As Figure 1 shown, taking the driving circuit in the prior art as an example, the driving circuit includes a pair of driving units. The pair of driving units respectively include an operational amplifier AMP_0 that outputs a positive voltage and an operational amplifier AMP_1 that outputs a negative voltage. To ensure the normal operation of the operational amplifier, the supply voltage range of the operational amplifier should be greater than or equal to its output voltage range.

[0034] For example, in a certain application scenario, the gray-scale voltage difference required by the liquid crystal panel is 4V. Then, the minimum supply voltage difference required by the operational amplifier AMP_0 is 4V. The first power supply terminal of the operational amplifier AMP_0 can be connected to a 4V supply voltage, and the second power supply terminal of the operational amplifier AMP_0 is grounded. Similarly, the minimum supply voltage difference required by the operational amplifier AMP_1 is 4V. The first power supply terminal of the operational amplifier AMP_1 is grounded, and the second power supply terminal of the operational amplifier AMP_1 is connected to a -4V supply voltage. However, in this case, the liquid crystal panel will have a flicker phenomenon due to the DC offset. Usually, the positive and negative gray-scale voltages need to be shifted upward as a whole to compensate for the DC offset. If shifted upward by 1V as a whole, the positive gray-scale voltage is 1V - 5V at this time, and the negative gray-scale voltage is -3V - 1V.

[0035] In order to enable the operational amplifier AMP_0 to normally output a gray-scale voltage of 1V - 5V, usually the first power supply terminal of the operational amplifier AMP_0 is connected to a 5V supply voltage, and the second power supply terminal of the operational amplifier AMP_0 is grounded to eliminate the influence of the offset voltage (since providing a 1V supply voltage at the second power supply terminal of the operational amplifier AMP_0 will require an additional power supply unit and cause additional power consumption, usually the second power supply terminal of the operational amplifier AMP_0 is grounded, which can also meet the working requirements of the operational amplifier AMP_0).

[0036] Similarly, in order to enable the operational amplifier AMP_1 to work properly, usually the first power supply terminal of the operational amplifier AMP_1 is connected to a power supply voltage of 1V (a low-dropout linear regulator can be added to the drive circuit to provide this power supply voltage), and the second power supply terminal of the operational amplifier AMP_0 is connected to a power supply voltage of -3V.

[0037] Since the first power supply terminal of the operational amplifier AMP_1 is connected to the 1V power supply voltage provided by the low-dropout linear regulator, the working current required by the first power supply terminal of the operational amplifier AMP_1 is provided by the low-dropout linear regulator, and the number of such operational amplifiers in the drive circuit is quite large, resulting in a significant increase in the power consumption of the drive circuit.

[0038] To make the above objects, features, and advantages of the present invention more obvious and understandable, the following describes the specific embodiments of the present invention in detail with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

[0039] An embodiment of the present invention provides a drive circuit. Refer to Figure 2 , and the following describes the drive circuit provided by the embodiment of the present invention.

[0040] Figure 2 is a schematic structural diagram of the drive circuit. Figure 2 The shown drive circuit includes:

[0041] A first drive unit 10 for outputting a first drive signal, the first drive signal being used to drive one of the first display unit or the second display unit, and the first power supply terminal A1 of the first drive unit 10 is connected to a first power supply voltage;

[0042] A second drive unit 20 for outputting a second drive signal, the second drive signal being used to drive the other of the first display unit or the second display unit;

[0043] A first power supply unit 30, the output terminal of the first power supply unit 30 is coupled to the second power supply terminal A2 of the first drive unit 10, the second power supply terminal A2 of the first drive unit 10 is coupled to the first power supply terminal B1 of the second drive unit 20, the first power supply unit 30 is used to provide a first adjustment current, and the second power supply terminal B2 of the second drive unit 20 is connected to a second power supply voltage.

[0044] In the specific implementation, the first power supply voltage is greater than the second power supply voltage, and the current is transmitted from the first drive unit 10 to the second drive unit 20.

[0045] In this embodiment, the first display unit and the second display unit may be liquid crystal capacitors in a liquid crystal display screen.

[0046] In other embodiments, the first display unit and the second display unit may also be organic light-emitting diodes in an OLED (Organic Light-Emitting Diode) display screen. The first display unit and the second display unit can be selected according to actual situations, and the present application does not limit this.

[0047] The first driving signal is a positive voltage, and the second driving signal is a negative voltage. Or, the first driving signal is a negative voltage, and the second driving signal is a positive voltage.

[0048] If the voltage input to the liquid crystal capacitor is a fixed voltage value, then over time, the liquid crystal capacitor will become polarized and gradually lose its optical properties. It is necessary to set up paired driving circuits to balance and cancel the voltage input to the liquid crystal capacitor to avoid damage to the deflection characteristics of the liquid crystal capacitor. Specifically, a positive voltage and a negative voltage are alternately input into the liquid crystal capacitor to ensure the characteristics of the liquid crystal capacitor.

[0049] In a non-limiting embodiment, the first power supply unit 30 is further configured to provide a third power supply voltage. To ensure the normal operation of the first driving unit 10 and the second driving unit 20, the voltage difference between the first power supply voltage and the third power supply voltage meets the operating conditions of the first driving unit 10, and the first power supply voltage is greater than the operating voltage required by the first power supply terminal of the first driving unit 10; the voltage difference between the third power supply voltage and the second power supply voltage meets the operating conditions of the second driving unit 20, and the third power supply voltage is greater than or equal to the operating voltage required by the first power supply terminal B1 of the second driving unit 20.

[0050] Specifically, the third power supply voltage may be less than or equal to the first target voltage of the second power supply terminal A2 of the first driving unit 10, where the first target voltage is the maximum value of the power supply voltage required by the second power supply terminal A2 of the first driving unit 10 when the first driving unit 10 is in an operating state; and the third power supply voltage is greater than or equal to the second target voltage of the first power supply terminal B1 of the second driving unit 20, where the second target voltage is the minimum value of the power supply voltage required by the first power supply terminal B1 of the second driving unit 20 when the second driving unit 20 is in an operating state. For example, if the power supply voltage required by the first power supply terminal of the first driving unit 10 is 5V and the power supply voltage required by the second power supply terminal A2 of the first driving unit 10 is 2V, the third power supply voltage can be set to 1V.

[0051] It should be noted that the voltage values of the first power supply voltage, the second power supply voltage, and the third power supply voltage can be selected according to actual situations, and the present application does not limit this.

[0052] Now, in combination with Figure 3 a detailed description of the drive circuit provided by the embodiments of the present invention will be given.

[0053] Figure 3 FIG. is a schematic structural diagram of a specific drive circuit provided by the embodiments of the present invention.

[0054] As Figure 3 shown, the first drive unit includes a first operational amplifier AMP1. The non-inverting input terminal of the first operational amplifier AMP1 is connected to a first control signal Ctrl1, and the inverting input terminal of the first operational amplifier AMP1 is coupled to the output terminal of the first operational amplifier AMP1.

[0055] The second drive unit includes a second operational amplifier AMP2. The non-inverting input terminal of the second operational amplifier AMP2 is connected to a second control signal Ctrl2, and the inverting input terminal of the second operational amplifier AMP2 is coupled to the output terminal of the second operational amplifier AMP2.

[0056] In the specific implementation manner, the output current of the second power supply terminal A2 of the first operational amplifier AMP1 is I_PSD; the current value of the current required by the first power supply terminal B1 of the second operational amplifier AMP2 when the second operational amplifier AMP2 is operating normally is a first target current, denoted as I_NSD; the first adjustment current provided by the first power supply unit 30 is Iout.

[0057] According to Kirchhoff's law, it can be known that the current input to the first power supply terminal B1 of the second operational amplifier AMP2 is a fixed value, and the following formula can be used to represent this relationship:

[0058] I_NSD = I_PSD + Iout (1)

[0059] According to formula (1), when I_PSD is less than I_NSD, the first power supply unit 30 needs to provide a first adjustment current Iout, and the current value of the first adjustment current Iout is the difference between the first target current I_NSD and the output current I_PSD of the second power supply terminal A2 of the first drive unit.

[0060] When I_PSD is equal to I_NSD, the first power supply unit 30 does not need to provide a first adjustment current Iout, and the current value of the first adjustment current Iout is zero.

[0061] When I_PSD is greater than I_NSD, the first power supply unit 30 does not need to provide the first regulated current Iout, and the current value of the first regulated current Iout is negative. That is, part of the output current of the second power supply terminal A2 of the first operational amplifier AMP1 will flow into the first power supply unit 30 to use the first power supply unit 30 to reduce part of the current to zero. Specifically, the current value of part of the current is the difference between the current value of the output current I_PSD of the second power supply terminal A2 of the first operational amplifier AMP1 and the first target current I_NSD. Among them, the negative current value of the first regulated current Iout indicates that the direction of the current is from the second power supply terminal A2 of the first operational amplifier AMP1 to the first power supply unit 30; correspondingly, the positive current value of the first regulated current Iout indicates that the direction of the current is from the first power supply unit 30 to the second power supply terminal A2 of the first operational amplifier AMP1.

[0062] The total power consumption of the first driving unit 10, the second driving unit 20, and the first power supply unit 30 can be expressed by the following formula:

[0063] P = V1×I_PSD + V2×I_NSD + V3×Iout (2)

[0064] Where P is the total power consumption, V1 is the first power supply voltage, V2 is the second power supply voltage, and V3 is the third power supply voltage.

[0065] According to Equation (2), when I_PSD is less than I_NSD, compared with only the first power supply unit 30 providing the first regulated current Iout with a current value of the first target current I_NSD, in the present invention, the second power supply terminal A2 of the first operational amplifier AMP1 can also provide the current I_PSD to the first power supply terminal B1 of the second operational amplifier AMP2. The first regulated current Iout provided by the first power supply unit 30 can be reduced, thereby reducing the total power consumption.

[0066] Furthermore, when I_PSD is equal to I_NSD or I_PSD is greater than I_NSD, the first power supply unit 30 only needs to provide the first regulated current Iout with a current value of zero, which can further reduce the total power consumption.

[0067] I_PSD and I_NSD can be configured when designing the driving circuit. According to the foregoing analysis, if I_PSD is configured to be the same as I_NSD, Iout can be made zero to achieve the best power-saving effect. To avoid I_PSD being less than I_NSD due to fluctuations in I_PSD during the actual operation of the driving circuit, I_PSD can be configured to be greater than I_NSD, thereby ensuring that Iout is zero.

[0068] It should be noted that I_PSD and I_NSD can be selected according to actual situations, and the present application does not limit this.

[0069] In a non - restrictive embodiment, the driving circuit further includes a switch unit 40. The first input terminal of the switch unit 40 is connected to the first driving signal drive1, and the second input terminal of the switch unit 40 is connected to the second driving signal drive2. The switch unit 40 is configured to input the first driving signal drive1 to the first display unit and input the second driving signal drive2 to the second display unit, or input the first driving signal drive1 to the second display unit and input the second driving signal drive2 to the first display unit.

[0070] In a specific implementation, the switch unit 40 can be a double - pole double - throw switch. The first input terminal of the double - pole double - throw switch is connected to the first driving signal drive1, the second input terminal of the double - pole double - throw switch is connected to the second driving signal drive2, the first output terminal of the double - pole double - throw switch is coupled to the first display unit, and the second output terminal of the double - pole double - throw switch is coupled to the second display unit.

[0071] In a non - restrictive embodiment, the first power supply unit 30 may include a low - dropout linear regulator (LDO, Low Dropout Regulator). The low - dropout linear regulator includes a MOS transistor, and the MOS transistor is used to output a first regulated current Iout and a third power supply voltage. The on - resistance of the MOS transistor can be configured as the resistance value corresponding to the third power supply voltage and the first regulated current Iout.

[0072] Specifically, the specific structure of the low - dropout linear regulator can be as Figure 4 shown.

[0073] Figure 4 It is a schematic diagram of the specific structure of a first power supply unit 30 provided by an embodiment of the present invention.

[0074] In this embodiment, the first power supply unit 30 can be a class - AB low - dropout linear regulator.

[0075] The first power supply unit 30 includes an operational amplifier AMP20, an operational amplifier AMP21, an NMOS transistor MN1, and an NMOS transistor MN2.

[0076] The non-inverting input terminal of operational amplifier AMP20 and the non-inverting input terminal of operational amplifier AMP21 are connected to a reference voltage Vref. The gate of NMOS transistor MN1 is coupled to the output terminal of operational amplifier AMP20. The drain of NMOS transistor MN1 is connected to an input voltage Vin (the input voltage Vin can be a power supply voltage). The source of NMOS transistor MN1 is coupled to the inverting input terminal of operational amplifier AMP20. The source of NMOS transistor MN1 is the output terminal of the first power supply unit 30, which can output a third supply voltage Vout.

[0077] The gate of NMOS transistor MN2 is coupled to the output terminal of operational amplifier AMP21. The drain of NMOS transistor MN2 is coupled to the source of NMOS transistor MN1. The source of NMOS transistor MN2 is grounded.

[0078] It should be noted that on the premise of being able to output the first regulated current, the third supply voltage Vout, and being able to reduce part of the current to zero, the structure of the first power supply unit 30 can also be selected according to the actual situation, and the present application does not limit this.

[0079] When I_PSD is less than I_NSD, the source of NMOS transistor MN2 outputs the first regulated current. The current value of the first regulated current is the difference between the first target current and the current value of the output current of the second power supply terminal A2 of the first driving unit, ensuring that the current flowing into the first power supply terminal B1 of the second driving unit reaches the first target current.

[0080] When I_PSD is greater than I_NSD, the first regulated current output by the source of NMOS transistor MN2 is zero, and part of the output current of the second power supply terminal A2 of the first driving unit will flow into the first power supply unit 30, and part of the current is reduced to zero through the source of NMOS transistor NM2.

[0081] Figure 5 It is a schematic diagram of the specific structure of another driving circuit provided by an embodiment of the present invention.

[0082] In a non-limiting embodiment, the driving circuit further includes a first gamma voltage unit 501, a second gamma voltage unit 502, and a second power supply unit 503, as well as a first digital-to-analog conversion unit 601, a second digital-to-analog conversion unit 602, and a third power supply unit 603.

[0083] The first gamma voltage unit 501 is used to provide a first gamma voltage. The first gamma voltage is used to generate a first driving signal drive1. The first power supply terminal C1 of the first gamma voltage unit 501 is connected to a first supply voltage;

[0084] The second gamma voltage unit 502 is used to provide a second gamma voltage, and the second gamma voltage is used to generate a second driving signal drive2. The second power supply terminal D2 of the second gamma voltage unit is connected to a second power supply voltage.

[0085] A second power supply unit 503, the output terminal of the second power supply unit 503 is coupled to the second power supply terminal C2 of the first gamma voltage unit 501. The second power supply terminal C2 of the first gamma voltage unit 501 is coupled to the first power supply terminal D1 of the second gamma voltage unit 502. The second power supply unit 503 is used to provide a second regulation current. The current value of the second regulation current is the difference between the second target current and the current value of the output current of the second power supply terminal C2 of the first gamma voltage unit 501 or zero. The second target current is configured as the current value of the current flowing into the first power supply terminal D1 of the second gamma voltage unit 502.

[0086] In the prior art, the first power supply terminal of one gamma voltage unit in a pair of gamma voltage units is connected to a first power supply voltage, and the second power supply terminal is grounded; the first power supply terminal of the other gamma voltage unit in the pair of gamma voltage units is connected to a third power supply voltage, and the second power supply terminal is connected to a second power supply voltage. The power supply unit needs to separately provide the current required for the first power supply terminal of the other gamma voltage unit. In this application, the output terminal of the second power supply unit 503 is coupled to the second power supply terminal C2 of the first gamma voltage unit 501, and the first power supply terminal D1 of the second gamma voltage unit 502 is coupled to the second power supply terminal C2 of the first gamma voltage unit 501. The current output from the second power supply terminal C2 of the first gamma voltage unit 501 can be input to the first power supply terminal D1 of the second gamma voltage unit 502, so that the output current provided by the second power supply unit 503 is greatly reduced, thereby reducing the power consumption of the driving circuit.

[0087] The first digital-to-analog conversion unit 601 is coupled between the first driving unit 10 and the first gamma voltage unit 501. The first digital-to-analog conversion unit 601 is used to convert the first gamma voltage into a first control signal corresponding to a first target gray value. The first control signal is used to generate a first driving signal drive1. The first power supply terminal E1 of the first digital-to-analog conversion unit 601 is connected to a first power supply voltage.

[0088] The second digital-to-analog conversion unit 602 is coupled between the second driving unit 20 and the second gamma voltage unit 502. The second digital-to-analog conversion unit 602 is used to convert the second gamma voltage into a second control signal corresponding to a second target gray value. The second control signal is used to generate a second driving signal drive2. The second power supply terminal F2 of the second digital-to-analog conversion unit 602 is connected to a second power supply voltage.

[0089] The output terminal of the third power supply unit 603 is coupled to the second power supply terminal E2 of the first digital-to-analog conversion unit 601. The second power supply terminal E2 of the first digital-to-analog conversion unit 601 is coupled to the first power supply terminal of the second digital-to-analog conversion unit 602. The third power supply unit 603 is configured to provide a third adjustment current. The current value of the third adjustment current is the difference between the third target current and the current value of the output current of the second power supply terminal E2 of the first digital-to-analog conversion unit 601, or zero. The third target current is configured as the current value of the current flowing into the first power supply terminal of the second digital-to-analog conversion unit 602.

[0090] In the prior art, the first power supply terminal of one digital-to-analog conversion unit in a pair of digital-to-analog conversion units is connected to a first power supply voltage, and the second power supply terminal is grounded; the first power supply terminal of the other digital-to-analog conversion unit in the pair of digital-to-analog conversion units is connected to a third power supply voltage, and the second power supply terminal is connected to a second power supply voltage. The power supply unit needs to separately provide the current required for the first power supply terminal of the other digital-to-analog conversion unit. In this application, the output terminal of the third power supply unit 603 is coupled to the second power supply terminal E2 of the first digital-to-analog conversion unit 601, and the first power supply terminal of the second digital-to-analog conversion unit 602 is coupled to the second power supply terminal E2 of the first digital-to-analog conversion unit 601. The current output from the second power supply terminal E2 of the first digital-to-analog conversion unit 601 can be input to the first power supply terminal of the second digital-to-analog conversion unit 602, so that the output current provided by the third power supply unit 603 is greatly reduced, thereby reducing the power consumption of the drive circuit.

[0091] It should be noted that the specific circuit structures of the first gamma voltage unit 501 and the second gamma voltage unit 502 can refer to the circuit structures of the gamma voltage units in the existing drive circuits; the specific circuit structures of the first digital-to-analog conversion unit 601 and the second digital-to-analog conversion unit 602 can refer to the circuit structures of the digital-to-analog converters in the existing drive circuits; the specific circuit structures of the second power supply unit 503 and the third power supply unit 603 can refer to Figure 4 the circuit structure of the first power supply unit 30 in

[0092] By improving the connection relationships of the first gamma voltage unit 501, the second gamma voltage unit 502, and the second power supply unit 503 in the drive circuit, and the connection relationships of the first digital-to-analog conversion unit 601, the second digital-to-analog conversion unit 602, and the third power supply unit 603, the power consumption of the drive circuit can be further saved, and the power consumption of the drive circuit can be greatly reduced. The power-saving principles of the above units can be referred to Figure 2 and Figure 3 the relevant descriptions in

[0093] It should be noted that in this embodiment, two or three of the first power supply unit 30, the second power supply unit 503, or the third power supply unit 603 can be combined. For example, the second power supply unit 503 and the third power supply unit 603 can share a power supply unit; or, the first power supply unit 30, the second power supply unit 503, and the third power supply unit 603 can share a power supply unit.

[0094] Figure 6 It is a schematic structural diagram of a driving circuit in a specific application scenario provided by an embodiment of the present invention.

[0095] In a specific application scenario, the driving circuit further includes a switch SW1, a switch SW2, and a switch SW3. The first end of the switch SW1 is connected to a power supply voltage, and the second end of the switch SW1 is coupled to the output end of the operational amplifier AMP1; the first output end of the switch SW2 is coupled to the output end of the operational amplifier AMP1, the second output end of the switch SW2 is coupled to the output end of the operational amplifier AMP2, and the input end of the switch SW2 is coupled to the output end of the first power supply unit 30; the first end of the switch SW3 is coupled to the output end of the operational amplifier AMP2, and the second end of the switch SW3 is grounded. In order to meet the requirements of certain application scenarios, the first display unit and the second display unit can be pre-charged with a voltage.

[0096] The signals EQ1 and EQ2 are control signals of the driving circuit. Among them, when the signal EQ1 is at a high potential, the operational amplifier AMP1 and the operational amplifier AMP2 stop working, the switch SW2 is turned on, and the switches SW1 and SW3 are turned off; when the signal EQ1 is at a low potential, the switch SW2 is turned off, and the switches SW1 and SW3 are turned off.

[0097] When the signal EQ2 is at a high potential, the operational amplifier AMP1 and the operational amplifier AMP2 stop working, the switches SW1 and SW3 are turned on, and the switch SW2 is turned off; when the signal EQ2 is at a low potential, the operational amplifier AMP1 and the operational amplifier AMP2 start working, and the switches SW1, SW2, and SW3 are turned off.

[0098] Now in combination with Figure 6 and Figure 7 it is described. Figure 7 It is a timing diagram of a driving circuit provided by an embodiment of the present invention when it is applied to a normally black panel to display a black screen.

[0099] In the time period from t0 to t1, the signal eq1 is at a high potential and the signal eq2 is at a low potential. The switch sw2 is turned on, and the switches sw1 and sw3 are turned off. The first power supply unit 30 outputs the third power supply voltage Vout, and the operational amplifiers AMP1 and AMP2 stop working. The signals S1 and S2 input to the first display unit and the second display unit are provided by the first power supply unit 30. At this time, the voltage values of the signals S1 and S2 are the same as that of the third power supply voltage Vout.

[0100] In the time period from t1 to t2, the signal eq1 is at a low potential and the signal eq2 is at a high potential. The switches sw1 and sw3 are turned on, the switch sw2 is turned off, and the operational amplifiers AMP1 and AMP2 stop working. The signal S1 is pre-charged to the power supply voltage VDD, and the signal S2 is pre-charged to the ground potential.

[0101] In the time period from t2 to t3, the signal eq1 is at a low potential and the signal eq2 is at a low potential. The switches sw1, sw2 and sw3 are turned off, and the operational amplifiers AMP1 and AMP2 start working. The signals output by the operational amplifiers AMP1 and AMP2 serve as the signal sources of the signals S1 and S2 respectively.

[0102] In the specific implementation, the conversion rates of AMP1 and AMP2 can be configured to be the same, that is, the rising and falling waveforms of the signal S1 are symmetric with the falling and rising waveforms of the signal S2, which can reduce the first adjustment current that the first power supply unit 30 needs to provide, thereby reducing the power consumption of the first power supply unit 30 (the saved current is shown by the dotted line of the first adjustment current Iout in the time period from t2 to t3).

[0103] In the time period from t3 to t4, the signal eq1 is at a low potential and the signal eq2 is at a high potential. The switches sw1 and sw3 are turned on, the switch sw2 is turned off, and the operational amplifiers AMP1 and AMP2 stop working. The signal S1 is pre-charged to the power supply voltage VDD, and the signal S2 is pre-charged to the ground potential.

[0104] In the time period from t4 to t5, the signal eq1 is at a high potential and the signal eq2 is at a low potential. The switch sw2 is turned on, and the switches sw1 and sw3 are turned off. The first power supply unit 30 outputs the third power supply voltage Vout, and the operational amplifiers AMP1 and AMP2 stop working. The signals S1 and S2 input to the first display unit and the second display unit are provided by the first power supply unit. At this time, the voltage values of the signals S1 and S2 are the same as that of the third power supply voltage Vout. The first power supply unit 30 outputs the first adjustment current Iout.

[0105] In the time period from t5 to t6, the signal eq1 is at a low potential and the signal eq2 is at a high potential. The switch sw1 and the switch sw3 are turned on, the switch sw2 is turned off, and the operational amplifiers AMP1 and AMP2 stop working. The signal S1 is pre-charged to the power supply voltage VDD, and the signal S2 is pre-charged to the ground potential.

[0106] In the time period from t6 to t7, the signal eq1 is at a low potential and the signal eq2 is at a low potential. The switch sw1, the switch sw2, and the switch sw3 are turned off, and the operational amplifiers AMP1 and AMP2 start working. The signals output by the operational amplifiers AMP1 and AMP2 serve as the signal sources for the signal S1 and the signal S2. At this time, the first regulation current that the first power supply unit 30 needs to provide can be reduced, thereby reducing the power consumption of the first power supply unit 30.

[0107] An embodiment of the present invention also discloses a chip, and the chip includes a driving circuit.

[0108] An embodiment of the present invention also discloses a display device, and the display device includes a plurality of display units. Each display unit includes a first display unit and a second display unit, and a driving circuit.

[0109] Each driving circuit can be connected to a display unit in a one-to-one correspondence, or each driving circuit can be connected to a plurality of display units.

[0110] In the embodiments of the present application, "a plurality of" means two or more.

[0111] In the embodiments of the present application, the first, second, etc. descriptions are only for schematic and distinguishing the described objects, without an order, and do not represent a special limitation on the number of devices in the embodiments of the present application, and cannot constitute any limitation to the embodiments of the present application.

[0112] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place, or they may be distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0113] In addition, in each embodiment of the present invention, the functional units can be integrated in a processing unit, or each unit can be physically included separately, or two or more units can be integrated in one unit. The above integrated units can be implemented in the form of hardware, or in the form of hardware plus software functional units.

[0114] The integrated unit implemented in the form of software functional units can be stored in a computer-readable storage medium. The above software functional units are stored in a storage medium and include several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute some steps of the methods described in various embodiments of the present invention.

[0115] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be subject to the scope defined by the claims.

Claims

1. A driving circuit, characterized in that, it includes: A first driving unit for outputting a first driving signal, the first driving signal being used to drive one of a first display unit or a second display unit, and a first power supply terminal of the first driving unit is connected to a first power supply voltage; A second driving unit for outputting a second driving signal, the second driving signal being used to drive the other of the first display unit or the second display unit; A first power supply unit, an output terminal of the first power supply unit is coupled to a second power supply terminal of the first driving unit, the second power supply terminal of the first driving unit is coupled to a first power supply terminal of the second driving unit, the first power supply unit is used to provide a first regulating current, and the second power supply terminal of the second driving unit is connected to a second power supply voltage, and the first power supply voltage is greater than the second power supply voltage.

2. The driving circuit according to claim 1, characterized in that, when a current value of an output current of the second power supply terminal of the first driving unit is less than a first target current, a current value of the first regulating current is a difference between the first target current and the current value of the output current of the second power supply terminal of the first driving unit; when the current value of the output current of the second power supply terminal of the first driving unit is equal to the first target current, the first regulating current is zero; the first target current is a current required by the first power supply terminal of the second driving unit when the second driving unit operates normally.

3. The driving circuit according to claim 1, characterized in that, when the current value of the output current of the second power supply terminal of the first driving unit is greater than the first target current, the first regulating current is negative, and a part of the output current of the second power supply terminal of the first driving unit flows into the first power supply unit, and a current value of the part of the current is a difference between the current value of the output current of the second power supply terminal of the first driving unit and the first target current.

4. The driving circuit according to claim 3, characterized in that, the first power supply unit is further used to reduce the part of the current to zero.

5. The driving circuit according to claim 1, characterized in that, the first power supply unit is further used to provide a third power supply voltage, the third power supply voltage is less than or equal to a first target voltage of the second power supply terminal of the first driving unit, the first target voltage is a maximum value of a power supply voltage required by the second power supply terminal of the first driving unit when the first driving unit is in an operating state; the third power supply voltage is greater than or equal to a second target voltage of the first power supply terminal of the second driving unit, the second target voltage is a minimum value of a power supply voltage required by the first power supply terminal of the second driving unit when the second driving unit is in an operating state.

6. The driving circuit according to claim 5, characterized in that, The first power supply unit includes a low dropout linear regulator, the low dropout linear regulator includes a MOS transistor, the MOS transistor is configured to output the first regulated current and the third supply voltage, and the on-resistance of the MOS transistor is configured to be a resistance value corresponding to the third supply voltage and the first regulated current.

7. The driving circuit according to claim 1, wherein, it further includes: a first gamma voltage unit configured to provide a first gamma voltage for generating the first driving signal, and a first power supply terminal of the first gamma voltage unit is connected to the first supply voltage; a second gamma voltage unit configured to provide a second gamma voltage for generating the second driving signal, and a second power supply terminal of the second gamma voltage unit is connected to the second supply voltage; a second power supply unit, an output terminal of the second power supply unit is coupled to the second power supply terminal of the first gamma voltage unit, the second power supply terminal of the first gamma voltage unit is coupled to the first power supply terminal of the second gamma voltage unit, and the first power supply unit is configured to provide a second regulated current, wherein a current value of the second regulated current is a difference between a second target current and a current value of an output current of the second power supply terminal of the first gamma voltage unit or zero, and the second target current is configured to be a current value of a current flowing into the first power supply terminal of the second gamma voltage unit.

8. The driving circuit according to claim 7, wherein, it further includes: a first digital-to-analog conversion unit coupled between the first driving unit and the first gamma voltage unit, the first digital-to-analog conversion unit is configured to convert the first gamma voltage into a first control signal corresponding to a first target gray value for generating the first driving signal, and a first power supply terminal of the first digital-to-analog conversion unit is connected to the first supply voltage; a second digital-to-analog conversion unit coupled between the second driving unit and the second gamma voltage unit, configured to convert the second gamma voltage into a second control signal corresponding to a second target gray value for generating the second driving signal, and a second power supply terminal of the second digital-to-analog conversion unit is connected to the second supply voltage; a third power supply unit, an output terminal of the third power supply unit is coupled to the second power supply terminal of the first digital-to-analog conversion unit, the second power supply terminal of the first digital-to-analog conversion unit is coupled to the first power supply terminal of the second digital-to-analog conversion unit, and the third power supply unit is configured to provide a third regulated current, wherein a current value of the third regulated current is a difference between a third target current and a current value of an output current of the second power supply terminal of the first digital-to-analog conversion unit or zero, and the third target current is configured to be a current value of a current flowing into the first power supply terminal of the second digital-to-analog conversion unit.

9. The driving circuit according to claim 8, wherein, The first driving unit includes a first operational amplifier. The positive input terminal of the first operational amplifier receives the first control signal, and the negative input terminal of the first operational amplifier is coupled to the output terminal of the first operational amplifier. The second driving unit includes a second operational amplifier. The positive input terminal of the second operational amplifier receives the second control signal, and the negative input terminal of the second operational amplifier is coupled to the output terminal of the second operational amplifier.

10. The driving circuit according to claim 1, wherein, it further includes: a switching unit. The first input terminal of the switching unit receives the first driving signal, and the second input terminal of the switching unit receives the second driving signal. The switching unit is configured to input the first driving signal to the first display unit and input the second driving signal to the second display unit, or input the first driving signal to the second display unit and input the second driving signal to the first display unit.

11. The driving circuit according to claim 1, wherein, the first display unit and the second display unit include liquid crystal capacitors.

12. A chip, wherein, it includes the driving circuit according to any one of claims 1 to 11.

13. A display device, wherein, it includes a plurality of display units. Each display unit includes a first display unit and a second display unit, and the driving circuit according to any one of claims 1 to 11.

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