TWI695362B - Light-emitting control circuit - Google Patents

Abstract

A light-emitting control circuit that includes a first transistor, a capacitor, a control unit, a first and a second discharging units and a voltage providing unit is provided. The first transistor outputs a light-emitting control signal according to a control signal. The control unit outputs a control signal according to a light-emitting clock signal. The first discharging unit includes a first and a second discharging transistors coupled in series. The first and the second discharging transistors operate according to a discharging control signal and the light emitting clock signal such that the first and the second discharging transistors discharges the control unit and the first transistor when conducted and stops discharging when unconducted. The voltage providing unit provides an inhibiting voltage to inhibit the discharging of the first discharging unit when the light emitting clock signal forces the first and the second discharging unit to stop discharging.

Description

Luminous control circuit

The invention relates to a control circuit, and in particular to a light-emitting control circuit.

A plurality of pixel units in a pixel array of a general display include photodiodes, and the transistors in the driving path are controlled by the light emission control voltage to further drive the photodiodes. However, the light-emitting control circuit used to provide the light-emitting control voltage is likely to be unstable due to poor design, and the low-state and high-state of the light-emitting control voltage may not be stable enough to achieve a sufficiently low or sufficiently high voltage level.

It can be seen that the above existing methods obviously still have inconveniences and shortcomings and need to be improved. In order to solve the above-mentioned problems, the related fields must spare no effort to find a solution, but a suitable solution has not been developed for a long time.

The summary of the present invention aims to provide a simplified summary of the disclosure so that the reader can have a basic understanding of the disclosure. This summary of the invention is not a complete overview of the disclosure, and it is not intended to point out important/critical elements of embodiments of the invention or to define the scope of the invention.

An object of the present invention is to provide a lighting control circuit to improve the problems of the prior art.

To achieve the above object, one technical aspect of the present invention relates to a light emission control circuit, including: a first transistor, a capacitor, a control unit, a first discharge unit, a second discharge unit, and a voltage supply unit. The first transistor includes a first terminal, an input control terminal, and a second terminal, wherein the first terminal is coupled to the voltage source, the second terminal is coupled to the light-emitting control terminal, and is used to emit light according to the control voltage received by the input control terminal The control terminal outputs the lighting control voltage. The capacitor is coupled between the input control terminal and the second terminal. The control unit is coupled between the voltage source and the input control terminal, and is used to output a control voltage at the input control terminal according to the light-emitting clock signal. The first discharge unit is coupled between the input control terminal and the discharge terminal, and includes a first discharge transistor and a second discharge transistor connected in series to the first connection node. The second discharge unit is coupled between the second end of the first transistor and the discharge end, wherein the discharge end is used to receive the light-emission clock signal, and the first discharge unit and the second discharge unit are used according to the discharge control signal and the light-emission clock The signal operates to discharge the input control terminal and the second terminal of the first transistor when turned on, and to stop discharging when turned off. The voltage supply unit is coupled to the first connection node to provide a discharge suppression voltage to the first connection node when the light-emitting clock signal stops the first discharge unit and the second discharge unit from discharging, further suppressing the discharge of the first discharge unit .

To achieve the above object, another technical aspect of the present disclosure relates to a light emission control circuit, including: a first transistor, a capacitor, a second transistor, a first discharge transistor, and a second discharge transistor. The first transistor includes a first terminal, an input control terminal, and a second terminal, wherein the first terminal is coupled to the voltage source, and the second terminal is coupled to the light-emitting control terminal, and is used to control the voltage received by the input control terminal The light-emission control voltage is output on the light-emission control terminal. The capacitor is coupled between the input control terminal and the second terminal. The second transistor includes a third terminal, a control terminal and a fourth terminal, wherein the third terminal is coupled to the voltage source, the fourth terminal is coupled to the input control terminal, and is used to receive the light-emitting clock signal at the control terminal to The clock signal outputs the control voltage at the input control terminal. The first discharge transistor includes a fifth terminal, a first discharge control terminal, and a sixth terminal, wherein the fifth terminal is coupled to the input control terminal, and the sixth terminal is coupled to the discharge terminal. The second discharge transistor includes a seventh end, a second discharge control end, and an eighth end, wherein the seventh end is coupled to the second end of the first transistor, and the eighth end is coupled to the discharge end. The discharge terminal is used to receive the light-emitting clock signal, and the first discharge transistor and the second discharge transistor are used to receive the discharge control signal according to the first discharge control terminal and the second discharge control terminal according to the discharge control signal and the light-emitting clock The signal operates to discharge the input control terminal and the second terminal of the first transistor when turned on, and to stop discharging when turned off.

Therefore, according to the technical content of the present invention, the embodiments of the present invention provide a light-emission control circuit to improve the stability of the light-emission control voltage in the high state and the low state, so that the light-emission control voltage can reach a sufficiently high level in the high state Level, and reach a sufficiently low level in the low state.

After referring to the embodiments below, those with ordinary knowledge in the technical field to which the present invention belongs can easily understand the basic spirit of the present invention and other inventive objectives, as well as the technical means and implementation aspects adopted by the present invention.

100‧‧‧Lighting control circuit

110‧‧‧Control unit

120‧‧‧ First discharge unit

130‧‧‧Second discharge unit

140‧‧‧ Voltage supply unit

180‧‧‧Pixel unit

190‧‧‧shift register

400‧‧‧Lighting control circuit

430‧‧‧Second discharge unit

500‧‧‧Lighting control circuit

540‧‧‧ Voltage supply unit

600‧‧‧Lighting control circuit

C‧‧‧Capacitance

D‧‧‧The first end

ECK‧‧‧luminous clock signal

EM‧‧‧Lighting control voltage

G‧‧‧Input control terminal

H, H+‧‧‧High state

L‧‧‧low state

N1‧‧‧ First connection node

N2‧‧‧Second connection node

P1‧‧‧ First time interval

P2‧‧‧Second time interval

P3‧‧‧ Third time interval

P4‧‧‧ Fourth time interval

P5‧‧‧ fifth time interval

Q‧‧‧Discharge control signal

S‧‧‧The second end

T1‧‧‧ First transistor

T2‧‧‧second transistor

T3‧‧‧third transistor

TD1‧‧‧The first discharge transistor

TD2‧‧‧Second discharge transistor

TD3‧‧‧The third discharge transistor

TD4‧‧‧The fourth discharge transistor

TDI1‧‧‧First discharge transistor

TDI2‧‧‧Second discharge transistor

VC‧‧‧Control voltage

VGH‧‧‧Voltage source

VI‧‧‧Discharge suppression voltage

In order to make the above and other objects, features, advantages and embodiments of the present invention more obvious and understandable, the drawings are described as follows:

FIG. 1 is a schematic diagram of a lighting control circuit according to an embodiment of the invention.

FIG. 2 is a schematic diagram of a control waveform according to an embodiment of the present invention.

FIGS. 3A-3E are schematic diagrams illustrating the operation of the lighting control circuit according to the embodiment shown in FIG. 1 of the present invention.

FIG. 4 is a schematic diagram of a lighting control circuit according to an embodiment of the invention.

FIG. 5 is a schematic diagram of a lighting control circuit according to an embodiment of the invention.

FIG. 6 is a schematic diagram of a lighting control circuit according to an embodiment of the invention.

According to the usual working methods, various features and elements in the drawings are not drawn to scale. The drawing method is to present the specific features and elements related to the present invention in an optimal manner. In addition, between different drawings, the same or similar element symbols are used to refer to similar elements/components.

In order to make the description of this disclosure more detailed and complete, the following provides an illustrative description of the implementation form and specific embodiments of the present invention; however, this is not the only form for implementing or using specific embodiments of the present invention. The embodiments cover the features of multiple specific embodiments, as well as the method steps and their sequence for constructing and operating these specific embodiments. However, other specific embodiments can also be used to achieve the same or equal functions and sequence of steps.

Unless otherwise defined in this specification, the science and technology used here The meaning of the vocabulary is the same as the meaning understood and used by those with ordinary knowledge in the technical field to which the present invention belongs. In addition, without conflicting with the context, the singular noun used in this specification covers the plural form of the noun; and the plural noun used also covers the singular form of the noun.

In addition, as used herein, "coupling" may refer to two or more elements making direct physical or electrical contact with each other, or indirectly making physical or electrical contact with each other, or may refer to two or more elements interoperating Or action.

FIG. 1 is a schematic diagram of a light emission control circuit 100 according to an embodiment of the invention. As shown, the light emission control circuit 100 includes a first transistor T1, a capacitor C, a control unit 110, a first discharge unit 120, a second discharge unit 130, and a voltage supply unit 140. The first transistor T1 includes a first terminal D, an input control terminal G, and a second terminal S.

In terms of connection, the first terminal D of the first transistor T1 is coupled to the voltage source VGH, the second terminal S is coupled to the light-emitting control terminal for outputting the light-emitting control voltage EM, and the input control terminal G is used for receiving control Voltage VC. The capacitor C is coupled between the input control terminal G and the second terminal S to provide the effect of coupling the voltage of the input control terminal G to the second terminal S.

The control unit 110 is coupled between the voltage source VGH and the input control terminal G, and can receive the light emitting clock signal ECK. In this embodiment, the control unit 110 includes a second transistor T2. The second transistor T2 includes a first terminal, a control terminal, and a second terminal. The first terminal of the second transistor T2 is coupled to the voltage source VGH. The control terminal of the second transistor T2 is used to receive the light-emitting clock signal ECK. The second terminal of the second transistor T2 is coupled to the input control terminal G.

The first discharge unit 120 is coupled between the input control terminal G and the discharge terminal for receiving the light-emitting clock signal ECK, and includes a first discharge transistor TD1 and a second discharge transistor TD2 connected in series to the first connection node N1 .

The first discharge transistor TD1 includes a first end, a control end, and a second end. The first end of the first discharge transistor TD1 is coupled to the input control terminal G, and the control end of the first discharge transistor TD1 is used to receive discharge control In the signal Q, the second end of the first discharge transistor TD1 is coupled to the first connection node N1.

The second discharge transistor TD2 includes a first end, a control end and a second end. The first end of the second discharge transistor TD2 is coupled to the first connection node N1, and the control end of the second discharge transistor TD2 is used to receive the discharge In the control signal Q, the second terminal of the second discharge transistor TD2 is coupled to the discharge terminal.

The second discharge unit 130 is coupled between the second terminal S of the first transistor T1 and the discharge terminal. In this embodiment, the second discharge unit 130 includes a third discharge transistor TD3. The third discharge transistor TD3 includes a first end, a control end, and a second end. The first end of the third discharge transistor TD3 is coupled to the second end S, and the control end of the third discharge transistor TD3 is used to receive discharge control In the signal Q, the second terminal of the third discharge transistor TD3 is coupled to the discharge terminal.

The voltage supply unit 140 is coupled to the first connection node N1. The voltage supply unit 140 is used to provide a discharge suppression voltage VI to the first connection node N1 to further suppress the discharge of the first discharge unit 120. In this embodiment, the voltage supply unit 140 includes a third transistor T3. The third transistor T3 includes a first terminal, a control terminal, and a second terminal. The first terminal of the third transistor T3 is coupled to the voltage source VGH, and the control terminal of the third transistor T3 is coupled to the light-emitting control terminal to receive light emission. For the control voltage EM, the second terminal of the third transistor T3 is coupled to the first connection node N1.

In one embodiment, the light emission control circuit 100 can be applied to a display panel (not shown). The light emission control terminal can be coupled to a row of pixel units 180 in the pixel array of the display panel to output a light emission control voltage EM to control the light emission of the photodiodes of the row of pixel units 180, and the discharge control signal Q is controlled by the corresponding The displacement register 190 driving the column of pixel units 180 is generated.

In order to make the operation mode of the light emission control circuit 100 of the embodiment of the present invention easy to understand, please refer to FIGS. 2 and 3A-3E together. FIG. 2 is a schematic diagram of a control waveform according to an embodiment of the present invention. 3A-3E are schematic diagrams illustrating the operation of the light-emitting control circuit 100 according to the embodiment shown in FIG. 1 of the present invention.

As shown in FIG. 2, a scan time corresponding to the column of pixel units 180 described above includes a first time interval P1, a second time interval P2, a third time interval P3, a fourth time interval P4, and a fifth Time interval P5. The following will use Figure 2 and Figures 3A-3E to explain in detail the operation and status of each signal and component in each time interval.

As shown in FIG. 3A, in the first time interval P1, the light-emission clock signal ECK is in the low state L and the discharge control signal Q is in the high state H with the first level.

At this time, the second transistor T2 included in the control unit 110 will be turned off due to the light-emitting clock signal ECK in the low state L (the symbol X indicates the off state in FIG. 3A). The first discharge transistor TD1 and the second discharge transistor TD2 of the first discharge unit 120 will be turned on due to the high state H of the discharge control signal Q and the low state L of the light emitting clock signal ECK to discharge the input control terminal G, The input control terminal G receives the control voltage VC of the low state L.

The first transistor T1 will be turned off because the input control terminal G receives the control voltage VC of the low state L (the symbol X indicates the off state in FIG. 3A). At this time, the third discharge transistor TD3 of the second discharge unit 130 turns on due to the high state H of the discharge control signal Q to discharge the second terminal S, so that the light emission control voltage EM is output to the low state L.

The control terminal of the third transistor T3 included in the voltage supply unit 140 will be turned off due to the light emission control voltage EM of the low state L (indicated by the symbol X in FIG. 3A to indicate the off state), so no voltage will be provided to the first connection Node N1. The first connection node N1 will be pulled to the low state L due to the discharge of the second discharge transistor TD2.

As shown in FIG. 3B, in the second time interval P2, the light-emission clock signal ECK is in a high state H and the discharge control signal Q is in a high state H+ having a second level greater than the first level.

At this time, the second transistor T2 included in the control unit 110 will be turned on due to the light-emitting clock signal ECK of the high state H. In an embodiment, the voltage of the voltage source VGH is in the high state H, so the on-control unit 110 will charge the input control terminal G according to the voltage of the voltage source VGH, and the control voltage VC will be in the high state H accordingly. Although the first discharge transistor TD1 and the second discharge transistor TD2 of the first discharge unit 120 receive the discharge control signal Q of the high state H+, the light emitting clock signal ECK is at the high state H, and the input control terminal G is also The high state H will make the voltage of the first terminal of the first discharge transistor TD1 (coupled to the input control terminal G) and the second terminal of the second discharge transistor TD2 (receive the light-emitting clock signal ECK) approximately the same and stop Discharge.

The first transistor T1 will receive a high state H because the input control terminal G The control voltage VC is turned on, and the light emitting control terminal coupled to the second terminal S is charged according to the voltage of the voltage source VGH, so that the light emitting control voltage EM becomes a high state H. Similar to the first discharge unit 120, the third discharge transistor TD3 of the second discharge unit 130 will be turned on due to the high state H+ of the discharge control signal Q, however, since the light emitting clock signal ECK is at the high state H, and the second terminal S also In the high state H, the voltages of the first terminal (coupled to the second terminal S) and the second terminal (receiving the light-emitting clock signal ECK) of the third discharge transistor TD3 will be approximately the same, and the discharge will stop.

Further, the control terminal of the third transistor T3 included in the voltage supply unit 140 will be turned on due to the light emission control voltage EM of the high state H, so the first connection node N1 will be charged to provide discharge suppression according to the voltage of the voltage source VGH The voltage VI reaches the first connection node N1. Since the voltage of the voltage source VGH is at the level of the high state H, the discharge suppression voltage VI will also raise the first connection node N1 to the high state H. The voltages of the first and second terminals of the first discharge transistor TD1 and the second discharge transistor TD2 of the first discharge unit 120 will therefore be approximately the same, achieving the effect of further suppressing discharge.

As shown in FIG. 3C, in the third time interval P3, the light-emission clock signal ECK is in the low state L and the discharge control signal Q is in the high state H with the first level.

At this time, the second transistor T2 included in the control unit 110 will be turned off due to the light-emitting clock signal ECK of the low state L (indicated by the symbol X in FIG. 3C to indicate the off state). The first discharge transistor TD1 and the second discharge transistor TD2 of the first discharge unit 120 will be turned on due to the high state H of the discharge control signal Q and the low state L of the light emitting clock signal ECK to discharge the input control terminal G, The input control terminal G receives the control voltage VC of the low state L.

The first transistor T1 will be turned off because the input control terminal G receives the control voltage VC of the low state L (indicated by the symbol X in FIG. 3C to indicate the off state). At this time, the third discharge transistor TD3 of the second discharge unit 130 turns on due to the high state H of the discharge control signal Q to discharge the second terminal S, so that the light emission control voltage EM outputs the low state L.

The control terminal of the third transistor T3 included in the voltage supply unit 140 will be turned off due to the light emission control voltage EM of the low state L (indicated by the symbol X in FIG. 3C to indicate the off state), so no voltage will be provided to the first connection Node N1. The first connection node N1 will be pulled to the low state L due to the discharge of the second discharge transistor TD2.

As shown in FIG. 3D, in the fourth time interval P4, the light-emission clock signal ECK is in the low state L and the discharge control signal Q is in the low state L.

At this time, the second transistor T2 included in the control unit 110 will be turned off due to the light-emitting clock signal ECK in the low state L (the symbol X indicates the off state in the 3D diagram). The first discharge transistor TD1 and the second discharge transistor TD2 of the first discharge unit 120 are turned off due to the low state L of the discharge control signal Q and the low state L of the light-emission clock signal ECK (indicated by symbol X in FIG. 3D) Off state) to stop discharging the input control terminal G. However, since the input control terminal G is already in the low state L in the third time interval P3, the control voltage VC received by the input control terminal G is still in the low state L.

The first transistor T1 will be turned off because the input control terminal G receives the control voltage VC of the low state L (the symbol X indicates the off state in the 3D diagram). However, since the second terminal S is already in the low state L in the third time interval P3, the light emission control voltage EM of the low state L will continue to be output at the light emission control terminal. At this time, the first The third discharge transistor TD3 of the second discharge unit 130 turns off the low state L due to the discharge control signal Q (indicated by X in the 3D diagram) to stop discharging the second terminal S.

The control terminal of the third transistor T3 included in the voltage supply unit 140 will be turned off due to the light-emission control voltage EM of the low state L (indicated by the symbol X in the 3D diagram to indicate the off state), so no voltage will be provided to the first connection Node N1.

As shown in FIG. 3E, in the fifth time interval P5, the light-emission clock signal ECK is in a high state H and the discharge control signal Q is in a low state L.

At this time, the second transistor T2 included in the control unit 110 will be turned on due to the light-emitting clock signal ECK of the high state H to charge the input control terminal G according to the voltage of the voltage source VGH. Although the light emitting clock signal ECK is in the high state H, the first discharge transistor TD1 and the second discharge transistor TD2 of the first discharge unit 120 will be turned off due to the low state L of the discharge control signal Q (marked in FIG. 3E X represents the off state) to stop discharging the input control terminal G. Therefore, in one embodiment, the control voltage VC will be a high state H+ having a second level greater than the first level due to continuous charging.

The first transistor T1 will be turned on because the input control terminal G receives the control voltage VC of the high state H+, and charges the light emitting control terminal coupled to the second terminal S according to the voltage of the voltage source VGH, so that the light emitting control voltage EM becomes High state H. At this time, the third discharge transistor TD3 of the second discharge unit 130 turns off the low state L due to the discharge control signal Q (indicated by the symbol X in FIG. 3E to indicate the off state) to stop discharging the second terminal S. At this time, the control voltage VC and the light emission control voltage EM are both in a high state, and both the first discharge unit 120 and the second discharge unit 130 have stopped discharging. Therefore, even after the fifth time interval P5, the control unit 110 After receiving the light-emitting clock signal ECK in the low state L, it is turned off, and the control voltage VC and the light-emission control voltage EM can also be maintained at the high-level level continuously.

The control terminal of the third transistor T3 included in the voltage supply unit 140 will be turned on due to the light emission control voltage EM of the high state H, so the first connection node N1 will be charged according to the voltage of the voltage source VGH to provide the discharge suppression voltage VI to The first connection node N1.

Therefore, after the operations of the first time interval P1 to the fifth time interval P5 are performed, the light emission control circuit 100 can output the waveform shown in FIG. 2 to reflect the photoelectricity of the corresponding pixel unit. The light emission of the polar body is driven and controlled. It should be noted that the waveform shown in FIG. 2 is only an example, and in other embodiments, other waveforms may be used for driving.

In some technologies, the input control terminal of the first transistor T1 is coupled to the first terminal in a diode connection manner, so that the input control terminal is directly controlled by the voltage source VGH to maintain the normally open state. When it is desired to output the low-state control voltage VC, the input control terminal of the first transistor T1 may not be closed smoothly due to insufficient discharge capacity of the first discharge unit 120, which further prevents the light emission control voltage EM from reaching a sufficiently low level Bit.

Therefore, the light-emitting control circuit 100 of the present invention can set the control unit 110 to turn off the control unit 110 through the light-emission clock signal ECK when the control voltage VC is to be maintained at a low state, ensuring that the low state of the control voltage VC is not affected Influence of voltage source VGH. Such a configuration can further ensure that the first transistor T1 is turned off, and the level of the light emission control voltage EM can be maintained in a sufficiently low state.

On the other hand, when the control voltage VC is to be maintained at a high state, the voltage The providing unit 140 can provide a discharge suppression voltage VI to the first connection node N1 when the light-emitting clock signal ECK causes the first discharge unit 120 to stop discharging, to further suppress the discharge of the first discharge unit 120 and ensure that the high state of the control voltage VC is not Being affected by the first discharge unit 120, the level of the light emission control voltage EM can be maintained at a sufficiently high state.

In the above embodiment, the second discharge unit 130 includes only one discharge transistor. However, in other embodiments, the second discharge unit 130 may also be provided with two discharge transistors connected in series according to the form of the first discharge unit 120, and a mechanism for suppressing discharge is provided at the connection point between the discharge transistors.

FIG. 4 is a schematic diagram of a light emission control circuit 400 according to an embodiment of the invention. The light emission control circuit 400 is similar to the light emission control circuit 100 shown in FIG. 1, and includes the first transistor T1, the capacitor C, the control unit 110, the first discharge unit 120, and the voltage supply unit 140, so the same components are no longer performed. Repeat. Compared with the previous embodiment, the light emission control circuit 400 of this embodiment includes a second discharge unit 430, and the second discharge unit 430 includes a third discharge transistor TD3 and a fourth discharge connected in series at the second connection node N2 Transistor TD4.

The third discharge transistor TD3 includes a first end, a control end, and a second end. The first end of the third discharge transistor TD3 is coupled to the second end S, and the control end of the third discharge transistor TD3 is used to receive discharge control In the signal Q, the second end of the third discharge transistor TD3 is coupled to the second connection node N2.

The fourth discharge transistor TD4 includes a first end, a control end, and a second end. The first end of the fourth discharge transistor TD4 is coupled to the second connection node N2, and the control end of the fourth discharge transistor TD4 is used to receive the discharge Control signal Q, fourth The second terminal of the discharge transistor TD4 is coupled to the discharge terminal.

Further, in this embodiment, the second end of the third transistor T3 included in the voltage supply unit 140 is coupled to the first connection node N1 and the second connection node N2.

Therefore, the above-mentioned voltage supply unit 140 provides a discharge suppression voltage VI to the first connection node N1 to suppress the discharge of the first discharge unit 120, and can also be applied to the second discharge unit 430. In more detail, the voltage supply unit 140 can provide the discharge suppression voltage VI to the second connection node N2, to ensure that the high state of the light emission control voltage EM is not affected by the second discharge unit 430, and further to the level of the light emission control voltage EM Can be maintained in a sufficiently high state.

FIG. 5 is a schematic diagram of a light emission control circuit 500 according to an embodiment of the invention. The light emission control circuit 500 is similar to the light emission control circuit 100 shown in FIG. 1, and includes the first transistor T1, the capacitor C, the control unit 110, the first discharge unit 120, and the second discharge unit 130, so they are no longer the same components. Repeat. Compared with the previous embodiment, the light emission control circuit 500 of this embodiment includes a voltage supply unit 540.

The voltage supply unit 540 is coupled to the first connection node N1. The voltage supply unit 540 is used to provide a discharge suppression voltage VI to the first connection node N1 to further suppress the discharge of the first discharge unit 120. In this embodiment, the voltage supply unit 540 includes a third transistor T3. The third transistor T3 includes a first end, a control end, and a second end. The third transistor T3 includes a first terminal, a control terminal, and a second terminal. The first terminal of the third transistor T3 is coupled to the lighting control terminal for charging to receive the lighting control voltage EM, and the control terminal of the third transistor T3 receives In the light-emitting clock signal ECK, the second end of the third transistor T3 is coupled to the first connection node N1.

When the light-emission control circuit 500 operates in the second time interval P2 shown in FIG. 2 for example, the control terminal of the third transistor T3 included in the voltage supply unit 540 will be turned on due to the light-emission signal ECK of the high state H, so The first connection node N1 is charged according to the high state H of the light emission control voltage EM, and a discharge suppression voltage VI can also be provided to the first connection node N1 to achieve the effect of suppressing discharge.

In yet another embodiment, the first end of the third transistor T3 included in the voltage supply unit 540 can also be coupled to the voltage source VGH, which can also be turned on according to the light emitting clock signal ECK of the high state H, instead The first connection node N1 is charged according to the voltage source VGH, and a discharge suppression voltage VI is provided to the first connection node N1 to achieve the effect of suppressing discharge.

It should be noted that the foregoing uses the voltage supply unit 140 as an example to provide different implementations of the voltage supply unit 140. In other embodiments, the structures of the control unit 110, the first discharge unit 120, and the second discharge unit 130 are not limited to the structures shown in FIG. In other embodiments, these units may also achieve the same effect through other structures.

FIG. 6 is a schematic diagram of a light emission control circuit 600 according to an embodiment of the invention. The light emission control circuit 600 is similar to the light emission control circuit 100 shown in FIG. 1 and includes the first transistor T1, the capacitor C, and the control unit 110, so the same elements will not be described in detail. Compared with the previous embodiment, the light emission control circuit 600 of this embodiment includes a first discharge transistor TDI1 and a second discharge transistor TDI2.

The first discharge transistor TDI1 includes a first end, a control end, and a second end. The first end of the first discharge transistor TDI1 is coupled to the input of the first transistor T1 Into the control terminal G, the control terminal of the first discharge transistor TDI1 is used to receive the discharge control signal Q, and the second terminal of the first discharge transistor TDI1 is coupled to the discharge terminal.

The second discharge transistor TDI2 includes a first end, a control end, and a second end. The first end of the second discharge transistor TDI2 is coupled to the second end S of the first transistor T1, and the control of the second discharge transistor TDI2 The terminal is used to receive the discharge control signal Q, and the second terminal of the second discharge transistor TDI2 is coupled to the discharge terminal.

Therefore, compared to the light emission control circuit 100 of FIG. 1, the light emission control circuit 600 does not include a voltage supply unit, so it is only provided between the input control terminal G and the second terminal S to the discharge terminal of the first transistor T1 A transistor is discharged. Therefore, in this embodiment, such a configuration method will only have the mechanism that the control unit 110 maintains the stability of the control voltage VC when it is in a low state, so that the light emission control voltage EM can be maintained at a sufficiently low level.

It can be known from the above embodiments of the present invention that the application of the present invention has the following advantages. The embodiment of the present invention improves the stability of the light emission control voltage EM in the high state and the low state by providing a light emission control circuit 100, so that the light emission control voltage EM can reach a sufficiently high level in the high state and Reach a sufficiently low level.

Although the above embodiments disclose specific examples of the present invention, they are not intended to limit the present invention. Those with ordinary knowledge in the technical field to which the present invention belongs, without departing from the principle and spirit of the present invention, should Various changes and modifications can be made to it, so the scope of protection of the present invention shall be defined by the scope of the accompanying patent application.

100‧‧‧Lighting control circuit

110‧‧‧Control unit

120‧‧‧ First discharge unit

130‧‧‧Second discharge unit

140‧‧‧ Voltage supply unit

180‧‧‧Pixel unit

190‧‧‧shift register

C‧‧‧Capacitance

D‧‧‧The first end

ECK‧‧‧luminous clock signal

EM‧‧‧Lighting control voltage

G‧‧‧Input control terminal

N1‧‧‧ First connection node

Q‧‧‧Discharge control signal

S‧‧‧The second end

T1‧‧‧ First transistor

T2‧‧‧second transistor

T3‧‧‧third transistor

TD1‧‧‧The first discharge transistor

TD2‧‧‧Second discharge transistor

TD3‧‧‧The third discharge transistor

VC‧‧‧Control voltage

VGH‧‧‧Voltage source

VI‧‧‧Discharge suppression voltage

Claims (11)

A lighting control circuit includes: a first transistor including a first terminal, an input control terminal and a second terminal, wherein the first terminal is coupled to a voltage source, and the second terminal is coupled to a light emitting The control terminal is used to output a light-emitting control voltage to the light-emitting control terminal according to a control voltage received by the input control terminal; a capacitor, coupled between the input control terminal and the second terminal; a control unit, coupled Between the voltage source and the input control terminal, for outputting the control voltage at the input control terminal according to a light-emitting clock signal; a first discharge unit, coupled between the input control terminal and the discharge terminal, and including A first discharge transistor and a second discharge transistor connected in series to a first connection node; a second discharge unit coupled between the second end and a discharge end of the first transistor, wherein the The discharge end is used to receive the light-emitting clock signal, and the first discharge unit and the second discharge unit are used to operate according to a discharge control signal and the light-emitting clock signal to respectively conduct the input control terminal and the first The second terminal of a transistor discharges and stops discharging when turned off; and a voltage supply unit, coupled to the first connection node, is used to enable the first discharge unit and the first When the two discharge cells stop discharging, a discharge suppression voltage is provided to the first connection node to further suppress the discharge of the first discharge cell. The light emission control circuit according to claim 1, wherein the second discharge unit includes a third discharge transistor. The light emission control circuit according to claim 1, wherein the second discharge unit includes a third discharge transistor and a fourth discharge transistor connected in series at a second connection node; wherein the voltage supply unit is further coupled to The second connection node to provide the discharge suppression voltage to the second connection node when the second discharge unit is turned off and the control unit is turned on to further suppress the discharge of the second discharge unit. The light emission control circuit according to claim 1, wherein the first discharge transistor includes: a first terminal coupled to the input control terminal; a control terminal for receiving the discharge control signal; and a second terminal , Coupled to the first connection node; wherein the discharge suppression voltage makes a voltage value of the second terminal of the first discharge transistor the same as another voltage value of the first terminal to suppress the first discharge transistor Discharge. The light emission control circuit according to claim 1, wherein the second discharge transistor includes: a first terminal coupled to the first connection node; a control terminal for receiving the discharge control signal; and a second End is coupled to the discharge end. The lighting control circuit according to claim 1, wherein the control The control unit includes: a second transistor, including: a first terminal coupled to the voltage source; a control terminal for receiving the light-emitting clock signal; and a second terminal coupled to the input control terminal . The light emission control circuit according to claim 1, wherein the voltage supply unit includes: a third transistor including: a first terminal coupled to the voltage source; and a control terminal coupled to the light emission control terminal Receiving the light emission control voltage; and a second terminal, coupled to the first connection node. The light emission control circuit according to claim 1, wherein the voltage providing unit includes: a third transistor including: a first terminal coupled to the light emission control terminal to receive the light emission control voltage; and a control terminal for To receive the light-emitting clock signal; and a second end, coupled to the first connection node. The light emission control circuit according to claim 1, wherein the light emission control terminal is coupled to a column of pixel cells in a pixel array, and the light emission control voltage is used to control the light emission of a photodiode of the pixel array, The discharge control The control signal is generated by a shift register corresponding to the pixel unit of the column. The light emission control circuit according to claim 8, wherein a scan time corresponding to the column of pixel units includes a first time interval, a second time interval, a third time interval, a fourth time interval, and a first Five time intervals; in the first time interval, the light-emitting clock signal is in a low state and the discharge control signal is in a high state with a first level, so that the control unit is turned off and the first discharge unit and The second discharge unit is turned on to discharge, further turning off the first transistor, so that the light-emitting control voltage outputs a low state; during the second time interval, the light-emitting clock signal is high and the discharge control signal is A high state having a second level greater than the first level to enable the control unit to turn on and stop the first discharge unit and the second discharge unit from discharging, further to make the control voltage high to cause the The first transistor is turned on so that the light emission control voltage outputs a high state, and the voltage supply unit provides the discharge suppression voltage to the first connection node to further suppress the discharge of the first discharge unit; during the third time interval, The light-emitting clock signal is in a low state and the discharge control signal is in a high state with the first level to turn off the control unit and turn on the first discharge unit and the second discharge unit for discharge, further enabling The first transistor is turned off, so that the light-emitting control voltage outputs a low state; in the fourth time interval, the light-emitting clock signal is low and the discharge control signal is low, so that the control unit is turned off and the The first discharge cell and the second discharge cell stop discharging, and further turn off the first transistor, so that the light emission control voltage outputs a low state: and During the fifth time interval, the light-emitting clock signal is in a high state and the discharge control signal is in a low state, so that the control unit is turned on and the first discharge unit and the second discharge unit are stopped from discharging, so that the first A transistor is turned on so that the light-emitting control voltage outputs a high state. A lighting control circuit includes: a first transistor including a first terminal, an input control terminal and a second terminal, wherein the first terminal is coupled to a voltage source, and the second terminal is coupled to a light emitting The control terminal is used to output a light-emitting control voltage to the light-emitting control terminal according to a control voltage received by the input control terminal; a capacitor coupled between the input control terminal and the second terminal; a second transistor, It includes a third terminal, a control terminal and a fourth terminal, wherein the third terminal is coupled to the voltage source, the fourth terminal is coupled to the input control terminal, and is used to receive a light-emitting clock at the control terminal A signal to output the control voltage at the input control terminal according to the light-emitting clock signal; a first discharge transistor includes a fifth terminal, a first discharge control terminal and a sixth terminal, wherein the fifth terminal is coupled Connected to the input control terminal, the sixth terminal is coupled to a discharge terminal; and a second discharge transistor including a seventh terminal, a second discharge control terminal and an eighth terminal, wherein the seventh terminal is coupled Connected to the second terminal of the first transistor, the eighth terminal is coupled to the discharge terminal; wherein the discharge terminal is used to receive the light-emitting clock signal, the first discharge transistor and the second discharge transistor Used to receive a discharge control signal according to the first discharge control terminal and the second discharge control terminal, according to the discharge control signal And the light-emitting clock signal operates to discharge the input control terminal and the second terminal of the first transistor when turned on, and to stop discharging when turned off.

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