CN217386637U - Drive circuit, light emitting diode drive chip, display panel and electronic equipment - Google Patents
Drive circuit, light emitting diode drive chip, display panel and electronic equipment Download PDFInfo
- Publication number
- CN217386637U CN217386637U CN202220182827.9U CN202220182827U CN217386637U CN 217386637 U CN217386637 U CN 217386637U CN 202220182827 U CN202220182827 U CN 202220182827U CN 217386637 U CN217386637 U CN 217386637U
- Authority
- CN
- China
- Prior art keywords
- switch
- unit
- voltage
- charge storage
- storage unit
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Control Of Indicators Other Than Cathode Ray Tubes (AREA)
Abstract
The utility model relates to a drive circuit, emitting diode driver chip, display panel and electronic equipment, drive circuit are used for driving at least one pixel unit, including voltage reference unit, at least one voltage transformation unit, and voltage reference unit provides the same first reference voltage for each voltage transformation unit; the at least one voltage conversion unit obtains a second reference voltage and a first current according to the first reference voltage and respectively supplies the second reference voltage and the first current to the at least one pixel unit, the second reference voltage is used for driving the at least one pixel unit, and the first current is used for driving a load in the at least one pixel unit. The utility model discloses drive circuit can come at least one pixel unit of simultaneous drive through providing the reference voltage of the same size, can provide the electric current for at least one pixel unit simultaneously to drive the load in at least one pixel unit, when being provided with luminescent device in pixel unit, can guarantee luminescent device's display effect.
Description
Technical Field
The utility model relates to a show the field, especially relate to a drive circuit, emitting diode driver chip, display panel and electronic equipment.
Background
With the continuous development of science and technology, the living standard of people is continuously improved, and the display capability of electronic equipment is also improved accordingly. Some light emitting devices with display function, such as light emitting diodes, etc., are sensitive in their characteristics, so that if the current flowing through the light emitting devices is unstable during the application process, the operating state of the light emitting devices will change, which affects the display effect; when the current is too large, the circuit is also susceptible to irreversible damage. Accordingly, the electronic device is generally provided with a driving circuit to drive the light emitting device, so that a relatively stable current can flow in the light emitting device, and the light emitting device can be in a relatively stable operating state and is not damaged as much as possible.
However, when the driving circuit of the prior art drives the light emitting devices with multiple channels at the same time, the accuracy of the channel currents of different channels may be reduced, so that the display effect is not good. Also, the light emitting device is usually disposed in a pixel unit, and when the pixel unit is operated, a load other than the light emitting device may need to be driven to adjust the magnitude of the current provided to the light emitting device. The prior art generally sets a load in a pixel unit to automatically draw current supplied to a light emitting device to maintain operation, but this mechanism further reduces the display effect of the light emitting device.
SUMMERY OF THE UTILITY MODEL
In view of this, the utility model provides a drive circuit, emitting diode driver chip, display panel and electronic equipment, according to the utility model discloses a drive circuit can drive at least one pixel unit simultaneously through providing the same size reference voltage to guarantee the current precision of each pixel unit in at least one pixel unit, drive circuit can provide the electric current for at least one pixel unit simultaneously, in order to drive the load in at least one pixel unit, when being provided with light emitting device in the pixel unit, can guarantee light emitting device's display effect.
According to an embodiment of the present invention, there is provided a driving circuit for driving at least one pixel unit, the driving circuit including a voltage reference unit, at least one voltage conversion unit, the voltage reference unit being configured to provide the same first reference voltage for each voltage conversion unit; the at least one voltage conversion unit is used for obtaining a second reference voltage and a first current according to the first reference voltage and respectively supplying the second reference voltage and the first current to the at least one pixel unit, the second reference voltage is used for driving the at least one pixel unit, and the first current is used for driving a load in the at least one pixel unit; the power ground wire of the at least one pixel unit and the power ground wire of the voltage reference unit are respectively connected with the same power ground wire outside the driving circuit through connecting wires.
In a possible implementation manner, for any voltage conversion unit in the at least one voltage conversion unit, the voltage conversion unit includes a first charge storage unit, a second charge storage unit, a first switch group, a second switch group, and a current generation unit, and the first charge storage unit is connected to the voltage reference unit through the first switch group; the second charge storage unit is connected with the first charge storage unit through a second switch group and is connected with one pixel unit through the current generation unit.
In a possible implementation manner, the first switch group includes a first switch and a second switch, the second switch group includes a third switch and a fourth switch, a first end of the first switch is connected to the output end of the voltage reference unit, a second end of the first switch is connected to the first end of the first charge storage unit, a second end of the first charge storage unit is connected to the second end of the second switch, and a first end of the second switch is connected to the power ground of the voltage reference unit; a first terminal of the third switch is connected to a first terminal of the first charge storage unit, a second terminal of the third switch is connected to a first terminal of the second charge storage unit, a second terminal of the second charge storage unit is connected to a second terminal of the fourth switch, and a first terminal of the fourth switch is connected to a second terminal of the first charge storage unit; the first end of the second charge storage unit is also connected with the current generation unit, and the second end of the second charge storage unit is also connected with the power ground wire of the pixel unit.
In a possible implementation manner, the current generating unit includes a fifth switch, a sixth switch, a seventh switch, an amplifier, and a first capacitor, a first end of the fifth switch is connected to the first end of the second charge storage unit and the first input end of the amplifier, and a second end of the fifth switch is connected to the first end of the first capacitor and the first end of the seventh switch; a first end of the sixth switch is connected to the second end of the first capacitor and the second input end of the amplifier, and a second end of the sixth switch is connected to the second end of the seventh switch and the output end of the amplifier; the output end of the amplifier is also connected with the pixel unit.
In a possible implementation manner, the voltage conversion unit is further configured to receive a control signal, where the control signal causes the switches in the second switch group to be turned off when the switches in the first switch group are turned on, the fifth switch and the sixth switch in the current generation unit are turned on, and the seventh switch is turned off; when the control signal enables the switches in the first switch group to be turned off, the switches in the second switch group are turned on, the fifth switch and the sixth switch in the current generation unit are turned off, and the seventh switch is turned on.
In one possible implementation manner, one duty cycle of the driving circuit includes a first phase and a second phase, in the first phase, the first charge storage unit is charged by the first reference voltage, and the current generation unit does not generate current; in the second phase, the first charge storage unit discharges to the second charge storage unit, and the current generation unit generates the first current; wherein the control signal is at a different level during the first phase and the second phase.
In a possible implementation manner, in a first phase of one duty cycle of the driving circuit, under the control of the control signal, the first switch and the second switch are turned on, the third switch and the fourth switch are turned off, and the first reference voltage is output to the first charge storage unit to charge the first charge storage unit; the fifth switch and the sixth switch are turned on, the seventh switch is turned off, the second input end of the amplifier is connected with the output end of the amplifier and is connected with the first input end of the amplifier through the first capacitor, and the amplifier does not generate current; in a second phase of one working cycle of the driving circuit, under the control of the control signal, the first switch and the second switch are turned off, the third switch and the fourth switch are turned on, the first charge storage unit discharges to the second charge storage unit, and the second charge storage unit outputs a third reference voltage at a first end; the fifth switch and the sixth switch are turned off, the seventh switch is turned on, the third reference voltage is input to the first input end of the amplifier, and the second input end of the amplifier is connected to the output end of the amplifier through the first capacitor, so that the output end of the amplifier outputs the second reference voltage and the first current.
In one possible implementation manner, the driving circuit is applied to a light emitting diode driving chip.
According to the utility model discloses a further embodiment provides a light emitting diode driver chip, include above drive circuit to and control circuit, control circuit passes through the signal line and connects the voltage transformation unit, control circuit is used for output control signal.
According to another embodiment of the present invention, a display panel is provided, which includes the above light emitting diode driving chip.
In a possible implementation manner, the display panel is one of a liquid crystal display panel, a micro light emitting diode display panel, a mini light emitting diode display panel, a quantum dot light emitting diode display panel, and an organic light emitting diode display panel.
According to another embodiment of the present invention, there is provided an electronic apparatus including the display panel described above.
In one possible implementation, the electronic device includes a display, a smartphone, or a portable device.
According to the utility model discloses drive circuit, through set up the voltage conversion unit between voltage reference unit and each pixel cell, make the first reference voltage of voltage reference unit output not directly export the pixel cell, but export for the pixel cell after the voltage conversion unit transform for second reference voltage, the voltage drop that produces when making the connecting wire of pixel cell flow current can not influence the voltage value of second reference voltage, even make drive circuit can provide the same size reference voltage in order to be used for driving at least one pixel cell simultaneously, thereby improve the current precision of each pixel cell in at least one pixel cell. And the driving circuit also provides a first current for driving the load in at least one pixel unit, so that when the light emitting device is arranged in the pixel unit, at least one pixel unit does not need to draw current from the current provided for the light emitting device to drive the load, and the precision of the current flowing through the light emitting device in the pixel unit can be further improved. In this way, the display effect of the light emitting device can be ensured.
Other features and aspects of the present invention will become apparent from the following detailed description of exemplary embodiments, which proceeds with reference to the accompanying drawings.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate exemplary embodiments, features, and aspects of the present invention and, together with the description, serve to explain the principles of the invention.
Fig. 1 shows a schematic structure of a prior art driving circuit.
Fig. 2 illustrates an exemplary application scenario according to an embodiment of the present invention.
Fig. 3 shows an exemplary structural schematic diagram of a driving circuit according to an embodiment of the present invention.
Fig. 4 shows an exemplary structure diagram of the voltage conversion unit 30 according to an embodiment of the present invention.
Fig. 5 shows an exemplary structure diagram of the voltage converting unit 30 according to an embodiment of the present invention.
Fig. 6 is a schematic diagram of an equivalent circuit structure of the voltage converting unit in the first stage according to an embodiment of the present invention.
Fig. 7 is a schematic diagram illustrating an equivalent circuit structure of the voltage converting unit in the second stage according to an embodiment of the present invention.
Detailed Description
Various exemplary embodiments, features and aspects of the present invention will be described in detail below with reference to the accompanying drawings. In the drawings, like reference numbers can indicate functionally identical or similar elements. While the various aspects of the embodiments are presented in drawings, the drawings are not necessarily drawn to scale unless specifically indicated.
The word "exemplary" is used exclusively herein to mean "serving as an example, embodiment, or illustration. Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments.
Furthermore, in the following detailed description, numerous specific details are set forth in order to provide a better understanding of the present invention. It will be understood by those skilled in the art that the present invention may be practiced without some of these specific details. In some instances, methods, means, elements and circuits that are well known to those skilled in the art have not been described in detail so as not to obscure the present invention.
Fig. 1 shows a schematic structure of a prior art driving circuit.
As shown in fig. 1, the related art driving circuit includes a voltage reference unit capable of generating a reference voltage having a voltage value Vref. The voltage reference unit is connected to a plurality of pixel units, and each pixel unit is provided with a light emitting device such as a Light Emitting Diode (LED), and the plurality of pixel units can be regarded as a plurality of display channels (CH1, CH2 … … CHX). When the prior art driving circuit is applied to a light emitting diode driving chip, several tens of channels are generally integrated. The anodes of the voltage reference units are respectively connected with the input ends (a1-ax) of the display channels, namely, the plurality of display channels (CH1, CH2 … … CHX) share the reference voltage Vref. The output ends (b1-bx) of the display channels are connected with corresponding power ground wires (pgnd1-pgndx), wherein each or a plurality of display channels are connected with the same power ground wire GND through independent wire bonding (bondwire). And the power ground wire is connected with the power ground wire of the cathode of the voltage reference unit through a routing.
The power ground wire is used as a common reference ground wire of zero potential of the drive circuit, and the power ground wire is used as a common reference ground wire of zero potential of the power supply. The driving circuit itself has a high voltage, and if the ground line resistance to ground is relatively high, a significant voltage drop occurs to generate large interference. Therefore, a power ground is generally provided for the drive circuit, separately from the power ground.
When the driving circuit structure is as shown in fig. 1, the voltage difference between the input end and the output end of each display channel enables current to flow through the display channel, and the current flows out of the display channel and then flows to the power ground through the routing. Since the wire bonding has a certain resistance, a voltage drop will occur on the wire bonding. Since the channels do not use the same wire bond, the voltage drop on each wire bond may be different, resulting in different power ground voltages (pgnd1-pgndx) for each display channel. Further, since each display channel is directly connected to the voltage reference unit, the voltage value of the actual reference voltage at the input terminal of each display channel will be different, thereby reducing the precision of the reference voltage and the precision of the current of each channel.
In addition, the reference voltage may not be directly supplied to the light emitting device after being input to each pixel unit, and for example, the reference voltage may be converted by a voltage conversion circuit (e.g., a digital-to-analog converter DAC) and then supplied to the light emitting device, so that the magnitude of the current flowing through the light emitting device may be adjusted. When such a pixel unit operates, a voltage conversion circuit or the like may be a load to be driven. In the prior art, the load generally automatically draws current supplied to the light emitting device to maintain operation, but this mechanism may further reduce the accuracy of current flowing through the light emitting device, i.e. further reduce the display effect of the light emitting device.
In view of this, the utility model provides a drive circuit, emitting diode driver chip, display panel and electronic equipment, according to the utility model discloses a drive circuit can drive at least one pixel unit simultaneously through providing the same size reference voltage to guarantee the current precision of each pixel unit in at least one pixel unit, drive circuit can provide the electric current for at least one pixel unit simultaneously, in order to drive the load in at least one pixel unit, when being provided with light emitting device in the pixel unit, can guarantee light emitting device's display effect.
Fig. 2 illustrates an exemplary application scenario according to an embodiment of the present invention.
As shown in fig. 2, in an application scenario, the driving circuit in the embodiment of the present invention can be used to drive at least one pixel unit 10 on the OLED display panel, wherein the at least one pixel unit 10 is respectively connected to the driving circuit, the driving circuit generates a reference voltage and a load current and provides the reference voltage and the load current to the at least one pixel unit 10, the reference voltage makes a current flow through the light emitting device in the at least one pixel unit 10 to drive the light emitting device in the pixel unit 10 to emit light, and the load current drives the load in the driving pixel unit 10.
Each pixel unit can be used as a display channel, and at least one display channel is provided with reference voltage and current by one voltage reference unit and at least one voltage conversion unit in the driving circuit. The power ground (PGND1-PGNDx) of each channel or each of several channels is connected to the power ground GND by a separate connecting wire (e.g., a wire bond). When a current flows through the light emitting device in the display channel, the current flowing through the light emitting device also flows into the connection line, causing a voltage drop on the connection line.
Fig. 3 shows an exemplary structural schematic diagram of a driving circuit according to an embodiment of the present invention. As shown in fig. 3, the present invention provides a driving circuit for driving at least one pixel unit 10, the driving circuit includes a voltage reference unit 20, at least one voltage conversion unit 30,
the voltage reference unit 20 is used for providing the same first reference voltage V1 for each voltage transformation unit 30;
the at least one voltage conversion unit 30 is configured to obtain a second reference voltage V2 and a first current I1 according to the first reference voltage V1 and respectively provide the second reference voltage V2 and the first current I1 to at least one pixel unit 10, wherein the second reference voltage V2 is configured to drive the at least one pixel unit 10, and the first current I1 is configured to drive a load in the at least one pixel unit 10;
the power ground line PGND (PGND1-PGNDx) of the at least one pixel cell 10 and the power ground line GND of the voltage reference cell 20 are respectively connected to the same power ground line GND outside the driving circuit through a connection line.
According to the utility model discloses drive circuit, through set up the voltage conversion unit between voltage reference unit and each pixel cell, make the first reference voltage of voltage reference unit output not directly export the pixel cell, but export for the pixel cell after the voltage conversion unit transform for second reference voltage, the voltage drop that produces when making the connecting wire of pixel cell flow current can not influence the voltage value of second reference voltage, even make drive circuit can provide the same size reference voltage in order to be used for driving at least one pixel cell simultaneously, thereby improve the current precision of each pixel cell in at least one pixel cell. And the driving circuit also provides a first current for driving the load in at least one pixel unit, so that when the light emitting device is arranged in the pixel unit, at least one pixel unit does not need to draw current from the current provided for the light emitting device to drive the load, and the precision of the current flowing through the light emitting device in the pixel unit can be further improved. In this way, the display effect of the light emitting device can be ensured.
Wherein the voltage reference unit 20 and the at least one pixel unit 10 may be implemented based on prior art, for example, reference may be made to the examples of the voltage reference unit and the pixel unit in the above and the related description of fig. 1. The first current I1 may be the load current in the related description of fig. 2. An exemplary structure of the voltage conversion unit 30 and its function in the embodiment of the present invention are described below.
Fig. 4 shows an exemplary structure diagram of the voltage converting unit 30 according to an embodiment of the present invention.
As shown in fig. 4, in one possible implementation, for any voltage converting unit of the at least one voltage converting unit 30, the voltage converting unit includes a first charge storing unit 301, a second charge storing unit 302, a first switch group 303, a second switch group 304 and a current generating unit 305,
the first charge storage unit 301 is connected with the voltage reference unit 20 through a first switch group 303;
the second charge storage unit 302 is connected to the first charge storage unit 301 through a second switch group 304, and is connected to one pixel unit 10 through the current generation unit 305.
The first charge storage unit 301 and the second charge storage unit 302 may respectively include at least one capacitor, or other devices capable of storing charges when charging and releasing charges when discharging, and fig. 4 exemplifies that the first charge storage unit 301 and the second charge storage unit 302 respectively include one capacitor. The utility model discloses do not do the restriction to the concrete structure of first charge storage unit, second charge storage unit.
In the driving circuit of the embodiment of the present invention, all the voltage converting units 30 can be connected to the same voltage reference unit 20, and each voltage converting unit 30 can be connected to one pixel unit 10 respectively. Referring to fig. 4, GND to which the first switch group 303 is connected may be a power ground of the voltage reference unit 20, and PGND to which the second switch group 304 is connected may be a power ground of the pixel unit 10 shown in fig. 4.
Fig. 5 shows an exemplary structure diagram of the voltage converting unit 30 according to an embodiment of the present invention.
As shown in fig. 5, in one possible implementation, the first switch group 303 includes a first switch S1 and a second switch S2, the second switch group 304 includes a third switch S3 and a fourth switch S4,
a first terminal S11 of the first switch S1 is connected to the output terminal of the voltage reference unit 20, a second terminal S12 of the first switch S1 is connected to the first terminal c11 of the first charge storage unit 301, a second terminal c12 of the first charge storage unit 301 is connected to the second terminal S22 of the second switch S2, and a first terminal S21 of the second switch S2 is connected to the power ground GND of the voltage reference unit 20;
the first end S31 of the third switch S3 is connected to the first end c11 of the first charge storage unit 301, the second end S32 of the third switch S3 is connected to the first end c21 of the second charge storage unit 302, the second end c22 of the second charge storage unit 302 is connected to the second end S42 of the fourth switch S4, and the first end S41 of the fourth switch S4 is connected to the second end c12 of the first charge storage unit 301;
the first terminal c21 of the second charge storage unit 302 is further connected to the current generating unit 305, and the second terminal c22 of the second charge storage unit 302 is further connected to the power ground PGND of the pixel unit 10.
As shown in fig. 5, in one possible implementation, the current generating unit 305 includes a fifth switch S5, a sixth switch S6, a seventh switch S7, an amplifier a1, and a first capacitor C1,
a first end S51 of the fifth switch S5 is connected to the first end C21 of the second charge storage unit 302 and the first input a1 of the amplifier a1, and a second end S52 of the fifth switch S5 is connected to the first end C31 of the first capacitor C1 and the first end S71 of the seventh switch S7;
a first end S61 of the sixth switch S6 is connected to the second end C32 of the first capacitor C1 and the second input end a2 of the amplifier a1, and a second end S62 of the sixth switch S6 is connected to the second end S72 of the seventh switch S7 and the output end A3 of the amplifier a 1;
the output terminal a3 of the amplifier a1 is also connected to the one pixel cell 10.
The above shows an exemplary structure of a drive circuit according to an embodiment of the present invention. An exemplary operation of the driving circuit according to an embodiment of the present invention is described below with reference to fig. 4 and 5.
In a possible implementation manner, the voltage converting unit 30 is further configured to receive a control signal, where the control signal causes the switches in the second switch group 304 to be turned off when the switches in the first switch group 303 are turned on, the fifth switch S5 and the sixth switch S6 in the current generating unit 305 are turned on, and the seventh switch S7 is turned off;
when the control signal turns off the switches in the first switch group 303, the switches in the second switch group 304 are turned on, the fifth switch S5 and the sixth switch S6 in the current generating unit 305 are turned off, and the seventh switch S7 is turned on.
For example, the switches in the first switch group 303, the second switch group 304 and the current generating unit 305 may be provided as switches in the form of fets, and the voltage converting unit 30 may be configured to realize the effects of turning off the switch in the second switch group 304, turning on the fifth switch S5 and the sixth switch S6 and turning off the seventh switch S7 when the switches in the first switch group 303 are controlled to be turned on by the control signal, and turning on the fifth switch S5 and the sixth switch S6 and turning on the seventh switch S7 when the switches in the first switch group 303 are controlled to be turned off by setting the types of fets in the first switch group 303, the second switch group 304 and the current generating unit 305 in cooperation with setting the level of the control signal. It should be understood by those skilled in the art that the switches in the first switch group 303, the second switch group 304 and the current generating unit 305 may be configured as other types of switches, and the invention is not limited thereto.
The realization mode of controlling the on and off of the switches in the switch group and the current generation unit by outputting the control signals to the switch group and the current generation unit is flexible, and the use complexity of the driving circuit can be reduced while the current precision of each pixel unit is ensured.
In one possible implementation, one working cycle of the driving circuit comprises a first phase and a second phase,
in the first phase, the first charge storage unit 301 is charged by the first reference voltage V1, and the current generation unit 305 generates no current;
in the second phase, the first charge storage unit 301 discharges to the second charge storage unit 302, and the current generation unit 305 generates the first current I1;
wherein the control signal is at a different level during the first phase and the second phase.
For example, it may be arranged that the voltage converting unit 30 receives only one kind of control signal, e.g. the first control signal, so that the first control signal has two levels, e.g. a first level and a second level. And the switches in the first switch group 303 may be set to be turned on when receiving the first control signal of the first level and turned off when receiving the first control signal of the second level, and the switches in the second switch group 304 may be set to be turned off when receiving the first control signal of the first level and turned on when receiving the first control signal of the second level. The fifth switch S5 and the sixth switch S6 in the setting current generating unit 305 are turned on when receiving the first control signal of the first level and turned off when receiving the first control signal of the second level, and the seventh switch S7 is turned off when receiving the first control signal of the second level and turned on when receiving the first control signal of the first level. In this case, by setting the control signals to have different levels in the first stage and the second stage, for example, setting the first control signal to be the first level in the first stage and the first control signal to be the second level in the second stage, the effects of turning off the switches in the first switch group 303, turning on the fifth switch S5 and the sixth switch S6 in the current generating unit 305, and turning off the seventh switch S7 in the second switch group are achieved, and the effects of turning on the switches in the second switch group 304, turning off the fifth switch S5 and the sixth switch S6 in the current generating unit 305, and turning on the seventh switch S7 in the first switch group 303 are achieved.
It will be appreciated by those skilled in the art that the control signals may be arranged in a plurality of ways, for example, the voltage converting unit 30 may be arranged to receive a first control signal and a second control signal with two different levels, the first control signal being used to control the switches of the first switch group 303 and the fifth switch S5 and the sixth switch S6 of the current generating unit 305, and the second control signal being used to control the switches of the second switch group 304 and the seventh switch S7 of the current generating unit 305, or the voltage converting unit 30 may be arranged to receive more control signals, each of which respectively controls one switch of the voltage converting unit 30. As long as can realize that drive circuit accomplishes the output of first electric current I1 and the charging and discharging of first reference voltage V1 according to control signal, and make charging and discharging not go on simultaneously can, the embodiment of the utility model provides a do not do the restriction to control signal's setting mode.
Charging and discharging are completed stage by stage, so that charging and discharging cannot be carried out simultaneously, namely the voltage reference unit is not directly conducted to the pixel unit but indirectly conducted through the first switch group and the second switch group, and therefore the situation that when current provided for the light-emitting device flows through connecting lines, different connecting lines generate different voltage drops, so that different power ground voltage values of the pixel units influence voltage values of second reference voltages received by the pixel units is avoided.
Exemplary operation of the elements of the driving circuit in the first and second phases of the present invention will be described. Fig. 6 and 7 are schematic diagrams illustrating equivalent circuit structures of the voltage conversion unit in the first stage and the second stage, respectively, according to an embodiment of the present invention.
As shown in fig. 6 and 7, in a first phase of one duty cycle of the driving circuit, under the control of the control signal, the first switch S1 and the second switch S2 are turned on, the third switch S3 and the fourth switch S4 are turned off, and the first reference voltage V1 is output to the first charge storage unit 301 to charge the first charge storage unit 301; the fifth switch S5 and the sixth switch S6 are turned on, the seventh switch S7 is turned off, the second input a2 of the amplifier a1 is connected to the output A3 of the amplifier a1 and is connected to the first input a1 of the amplifier a1 through the first capacitor C1, so that the amplifier a1 does not generate current;
in a second phase of one duty cycle of the driving circuit, under the control of the control signal, the first switch S1 and the second switch S2 are turned off, the third switch S3 and the fourth switch S4 are turned on, the first charge storage unit 301 discharges to the second charge storage unit 302, and the second charge storage unit 302 outputs a third reference voltage V3 at a first terminal c 21; the fifth switch S5 and the sixth switch S6 are turned off, the seventh switch S7 is turned on, the third reference voltage V3 is input to the first input terminal a1 of the amplifier a1, the second input terminal a2 of the amplifier a1 is connected to the output terminal A3 of the amplifier a1 through the first capacitor C1, and the output terminal A3 of the amplifier a1 outputs the second reference voltage V2 and the first current I1.
For example, in the first stage, the first switch S1 and the second switch S2 are turned on, the third switch S3 and the fourth switch S4 are turned off, the fifth switch S5 and the sixth switch S6 are turned on, and the seventh switch S7 is turned off, so that the driving circuit is equivalent to the circuit diagram shown in fig. 6. In this case, the voltage difference across the first charge storage unit 301 is equal to the first reference voltage V1, and the first reference voltage V1 can be regarded as being stored in the first charge storage unit 301 in the form of a charge, i.e. the voltage reference unit 20 outputs the first reference voltage V1 to charge the first charge storage unit 301. The voltage difference across the second charge storing unit 302 is equal to the original output voltage of the first terminal of the second charge storing unit 302 before entering the first phase, and the original output voltage can also be regarded as being stored in the second charge storing unit 302 in the form of charge, i.e. the second charge storing unit 302 stores the original output voltage of the first terminal of the second charge storing unit 302 before entering the first phase. The second input terminal a2 of the amplifier is connected to the output terminal A3 of the amplifier a1, so that the voltages of the second input terminal a2 and the output terminal A3 are equal, and the output terminal A3 is also connected to the first input terminal a1 through the first capacitor C1, so that no current is generated by the amplifier a 1.
In the second stage, the first switch S1 and the second switch S2 are turned off, the third switch S3 and the fourth switch S4 are turned on, the fifth switch S5 and the sixth switch S6 are turned off, the seventh switch S7 is turned on, and the driving circuit is equivalent to the circuit diagram shown in fig. 7. In this case, the voltage difference across the first charge storage unit 301 in the first phase is superimposed with the voltage difference across the second charge storage unit 302 in the first phase, which can be seen as the first charge storage unit 301 releasing the first reference voltage V1 stored in charge form to the second charge storage unit 302, i.e. the first charge storage unit 301 discharging to the second charge storage unit 302, so that the second charge storage unit 302 outputs the third reference voltage V3. The third reference voltage V3 is output to the first input terminal of the amplifier a1, the second input terminal a2 of the amplifier a1 is connected to the output terminal A3 of the amplifier a1 through the first capacitor C1, and the voltages of the second input terminal a2 and the output terminal A3 are unequal, so that the amplifier a1 generates the second reference voltage V2 and the first current I1 according to the third reference voltage V3 and outputs the second reference voltage V2 and the first current I1 through the output terminal A3.
As can be seen from the equivalent circuit diagrams of the first stage and the second stage, the voltage reference unit 20 does not form a path with the pixel unit 10 in the first stage and the second stage, and therefore, the accuracy of the voltage value of the first reference voltage V1 output by the voltage reference unit is not affected no matter how much voltage drop exists on the connection line of the power ground line and the power ground line of the pixel unit, and further, the accuracy of the voltage value of the second reference voltage V2 output by the voltage conversion unit is not affected. In this way, the accuracy of the second reference voltage is improved, and therefore when the second reference voltage is output to the pixel unit, the accuracy of the current flowing through the light emitting device in the pixel unit is also improved. Meanwhile, the current generated by the driving circuit is also output to the pixel unit, so that the load in the pixel unit can be driven, and the current precision of the light-emitting device flowing in the pixel unit is further improved.
It should be understood by those skilled in the art that the structure of each voltage conversion unit in at least one voltage conversion unit 30 may be the example of fig. 3, and may also include more devices, as long as each voltage conversion unit can connect to the same voltage reference unit and connect to the power ground through an independent connection line, so that the voltage reference unit and the pixel unit do not directly form a path, and the voltage output by the voltage reference unit can be stably output to the pixel unit through the voltage conversion unit and can provide the effect that the current drives the load in the pixel unit, which is not limited by the embodiment of the present invention.
It should be noted that each unit in the embodiments of the present invention may be implemented by a hardware circuit.
In one possible implementation manner, the driving circuit is applied to a light emitting diode driving chip.
The LED driving chip may include a constant current LED driving chip, such as an LED Driver 8603. The utility model discloses when drive circuit used LED Driver8603 on, at least one display channel that at least one pixel element supported as LED Driver8603 can make the current precision of each display channel not receive the influence of connecting wire voltage drop basically.
The embodiment of the utility model provides a still provide a light emitting diode driver chip, including above drive circuit to and control circuit, control circuit passes through the signal line and connects the voltage transformation unit, control circuit is used for exporting control signal.
When the voltage conversion unit is arranged to receive only one control signal, the driving circuit and the control circuit are connected through only one signal line, and wiring complexity of the light-emitting diode driving chip can be reduced.
The embodiment of the utility model provides a still provide a display panel, including above emitting diode driver chip.
The display panel may also be a large-screen display panel, for example, a large-sized LED display screen disposed indoors or outdoors, or a combined display screen with a larger display capability obtained by combining a plurality of display panels.
In a possible implementation manner, the display panel may include a liquid crystal display panel, a Micro Light Emitting Diode (Micro led) display panel, a Mini led display panel, a Quantum dot Light Emitting Diode (QLED) display panel, or an Organic Light-Emitting Diode (OLED) display panel.
The embodiment of the utility model provides a still provide an electronic equipment, including above display panel.
In one possible implementation, the electronic device comprises a display, a smartphone, or a portable device.
The circuit of the embodiment of the present invention can be various electronic devices with display function, which are also called User Equipment (UE), Mobile Station (MS), Mobile Terminal (MT), etc., and is a device providing voice and/or data connectivity for users, for example, a handheld device with wireless connection function, a vehicle-mounted device, etc. Currently, some examples of terminals are: a mobile phone (mobile phone), a tablet computer, a notebook computer, a palm top computer, a Mobile Internet Device (MID), a wearable device, a Virtual Reality (VR) device, an Augmented Reality (AR) device, a wireless terminal in industrial control (industrial control), a wireless terminal in self-driving (self-driving), a wireless terminal in remote operation (remote medical supply), a wireless terminal in smart grid (smart grid), a wireless terminal in transportation safety (smart security), a wireless terminal in city (smart city), a wireless terminal in home (smart home), a wireless terminal in car networking, and the like.
The above description is only for the specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto, and any person skilled in the art can easily think of the changes or substitutions within the technical scope of the present invention, and all should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
Claims (13)
1. A driving circuit for driving at least one pixel cell, the driving circuit comprising a voltage reference unit, at least one voltage conversion unit,
the voltage reference unit is used for providing the same first reference voltage for each voltage conversion unit;
the at least one voltage conversion unit is used for obtaining a second reference voltage and a first current according to the first reference voltage and respectively supplying the second reference voltage and the first current to the at least one pixel unit, the second reference voltage is used for driving the at least one pixel unit, and the first current is used for driving a load in the at least one pixel unit;
the power ground wire of the at least one pixel unit and the power ground wire of the voltage reference unit are respectively connected with the same power ground wire outside the driving circuit through connecting wires.
2. The driving circuit according to claim 1, wherein for any of the at least one voltage converting unit, the voltage converting unit comprises a first charge storing unit, a second charge storing unit, a first switch group, a second switch group, and a current generating unit,
the first charge storage unit is connected with the voltage reference unit through a first switch group;
the second charge storage unit is connected with the first charge storage unit through a second switch group and is connected with one pixel unit through the current generation unit.
3. The drive circuit according to claim 2, wherein the first switch group includes a first switch and a second switch, the second switch group includes a third switch and a fourth switch,
the first end of the first switch is connected with the output end of the voltage reference unit, the second end of the first switch is connected with the first end of the first charge storage unit, the second end of the first charge storage unit is connected with the second end of the second switch, and the first end of the second switch is connected with the power supply ground wire of the voltage reference unit;
a first terminal of the third switch is connected to a first terminal of the first charge storage unit, a second terminal of the third switch is connected to a first terminal of the second charge storage unit, a second terminal of the second charge storage unit is connected to a second terminal of the fourth switch, and a first terminal of the fourth switch is connected to a second terminal of the first charge storage unit;
the first end of the second charge storage unit is also connected with the current generation unit, and the second end of the second charge storage unit is also connected with the power ground wire of the pixel unit.
4. The driving circuit according to claim 3, wherein the current generating unit includes a fifth switch, a sixth switch, a seventh switch, an amplifier, and a first capacitor,
a first end of the fifth switch is connected with a first end of the second charge storage unit and a first input end of the amplifier, and a second end of the fifth switch is connected with a first end of the first capacitor and a first end of the seventh switch;
a first end of the sixth switch is connected to the second end of the first capacitor and the second input end of the amplifier, and a second end of the sixth switch is connected to the second end of the seventh switch and the output end of the amplifier;
the output end of the amplifier is also connected with the pixel unit.
5. The driving circuit of claim 4, wherein the voltage converting unit is further configured to receive a control signal, the control signal causes the switches in the second switch group to be turned off when the switches in the first switch group are turned on, the fifth and sixth switches in the current generating unit are turned on, and the seventh switch is turned off;
when the control signal enables the switches in the first switch group to be turned off, the switches in the second switch group are turned on, the fifth switch and the sixth switch in the current generation unit are turned off, and the seventh switch is turned on.
6. The driving circuit of claim 5, wherein one duty cycle of the driving circuit comprises a first phase and a second phase,
in the first phase, the first charge storage unit is charged by the first reference voltage, and the current generation unit generates no current;
in the second phase, the first charge storage unit discharges to the second charge storage unit, and the current generation unit generates the first current;
wherein the control signal is different in level in the first phase and the second phase.
7. The driving circuit according to claim 6, wherein in a first phase of one duty cycle of the driving circuit, under the control of the control signal, the first switch and the second switch are turned on, the third switch and the fourth switch are turned off, the first reference voltage is output to the first charge storage unit, and the first charge storage unit is charged; the fifth switch and the sixth switch are turned on, the seventh switch is turned off, the second input end of the amplifier is connected with the output end of the amplifier and is connected with the first input end of the amplifier through the first capacitor, and the amplifier does not generate current;
in a second phase of one working cycle of the driving circuit, under the control of the control signal, the first switch and the second switch are turned off, the third switch and the fourth switch are turned on, the first charge storage unit discharges to the second charge storage unit, and the second charge storage unit outputs a third reference voltage at a first end; the fifth switch and the sixth switch are turned off, the seventh switch is turned on, the third reference voltage is input to the first input end of the amplifier, and the second input end of the amplifier is connected to the output end of the amplifier through the first capacitor, so that the output end of the amplifier outputs the second reference voltage and the first current.
8. The driving circuit according to any one of claims 1 to 7, wherein the driving circuit is applied to a light emitting diode driving chip.
9. A light emitting diode driving chip, comprising the driving circuit as claimed in any one of claims 1 to 8, and a control circuit, wherein the control circuit is connected to the voltage converting unit through a signal line, and the control circuit is configured to output a control signal.
10. A display panel characterized by comprising the light emitting diode driving chip according to claim 9.
11. The display panel of claim 10, wherein the display panel is one of a liquid crystal display panel, a micro light emitting diode display panel, a mini light emitting diode display panel, a quantum dot light emitting diode display panel, and an organic light emitting diode display panel.
12. An electronic device characterized in that it comprises a display panel as claimed in claim 10 or 11.
13. The electronic device of claim 12, wherein the electronic device comprises a display, a smartphone, or a portable device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202220182827.9U CN217386637U (en) | 2022-01-20 | 2022-01-20 | Drive circuit, light emitting diode drive chip, display panel and electronic equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202220182827.9U CN217386637U (en) | 2022-01-20 | 2022-01-20 | Drive circuit, light emitting diode drive chip, display panel and electronic equipment |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN217386637U true CN217386637U (en) | 2022-09-06 |
Family
ID=83098804
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202220182827.9U Active CN217386637U (en) | 2022-01-20 | 2022-01-20 | Drive circuit, light emitting diode drive chip, display panel and electronic equipment |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN217386637U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114429750A (en) * | 2022-01-20 | 2022-05-03 | 集璞(上海)科技有限公司 | Drive circuit, light emitting diode drive chip, display panel and electronic equipment |
-
2022
- 2022-01-20 CN CN202220182827.9U patent/CN217386637U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114429750A (en) * | 2022-01-20 | 2022-05-03 | 集璞(上海)科技有限公司 | Drive circuit, light emitting diode drive chip, display panel and electronic equipment |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN100397456C (en) | Driving circuit used for organic electroluminescent device | |
| US8411077B2 (en) | DC-DC converter and organic light emitting display device using the same | |
| US9123286B2 (en) | Power generator having a power selector and organic light emitting display device using the same | |
| US9535440B2 (en) | DC-DC converter and organic light emitting display device using the same | |
| US7528807B2 (en) | Power supply and driving method thereof and apparatus and method for driving electro-luminescence display device using the same | |
| KR101903703B1 (en) | DC-DC Converter and Organic Light Emitting Display including The Same | |
| TW527500B (en) | Voltage booster circuit, voltage boosting method, and electronic unit | |
| US20100253154A1 (en) | Switch circuit of dc/dc converter configured to conduct various modes for charging/discharging | |
| JP2007074797A (en) | Switching power supply and electronic device using the same | |
| US10461623B2 (en) | Voltage converter circuit, electronic device including the same and voltage conversion method | |
| US20130235017A1 (en) | Power supply unit and organic light emitting display including the same | |
| JP2007244078A (en) | Switching power supply, drive circuit therefor, and electronic equipment using them | |
| KR102395148B1 (en) | Dc-dc converter and display device having the same | |
| CN217386637U (en) | Drive circuit, light emitting diode drive chip, display panel and electronic equipment | |
| TW201731202A (en) | DC-DC converter and display apparatus having the same | |
| CN217239024U (en) | Drive circuit, light emitting diode drive chip, display panel and electronic equipment | |
| CN107623440A (en) | Voltage conversion circuit and power supply switch circuit | |
| KR20150026488A (en) | Dc-dc converter and organic light emitting display including the same | |
| US8379008B2 (en) | Organic light emitting display device and power supply unit for the same | |
| CN114360456A (en) | Drive circuit, light emitting diode drive chip, display panel and electronic equipment | |
| KR101633426B1 (en) | Power supplying apparatus of Organic Light Emitting Display | |
| US20090243989A1 (en) | Display apparatus | |
| US11587506B2 (en) | Pixel structure, driving method thereof and display device | |
| CN114429750A (en) | Drive circuit, light emitting diode drive chip, display panel and electronic equipment | |
| CN100471018C (en) | Dc-dc conveter and organiclight emitting display using the same |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |