Light sensor voltage stabilizing circuit, light sensor driving method, and display device

Abstract

This application discloses a photosensitive voltage regulator circuit, a photosensitive sensor driving method, and a display device. The photosensitive voltage regulator circuit includes a photosensitive sensor and a compensation module. The photosensitive sensor adopts a thin-film transistor structure. The receiving end of the compensation module is connected to the output end of the photosensitive sensor to receive the output signal of the photosensitive sensor. The output end of the compensation module is connected to the port of the photosensitive sensor to send a compensation signal to the port of the photosensitive sensor to increase the voltage of the output signal during the voltage rise phase. Through the above design, the output stability of the photosensitive sensor can be improved, and the dimming effect of the display screen can be improved.

Description

Technical Field

[0001] This application relates to the field of display technology, and in particular to a light sensor voltage regulator circuit, a light sensor driving method, and a display device. Background Technology

[0002] Liquid crystal displays (LCDs) and organic light-emitting diodes (OLEDs) are commonly used as screens in electronic devices such as mobile phones, televisions, and computers due to their advantages of being lightweight, thin, low-power, high-brightness, and high-quality image quality. These devices utilize multiple light sensors integrated into the LCD or OLED to detect the intensity of external light at different locations, adjusting the brightness of the displayed image based on changes in ambient light. For LCDs and OLEDs, light sensors can be implemented either through external photosensitive devices or by embedding thin-film transistors (TFTs) within the display panel. The latter approach, which reduces the bezel area of ​​the display panel and improves manufacturing efficiency, is becoming increasingly widespread in the display industry.

[0003] When the monitor is first turned on, or when the light sensor is affected by factors such as ambient temperature, the output of the light sensor may become unstable, affecting the dimming effect of the displayed image. Summary of the Invention

[0004] The purpose of this application is to provide a photosensitive voltage regulator circuit, a photosensitive driving method, and a display device to improve the output stability of the photosensitive sensor.

[0005] This application discloses a voltage regulator circuit for an optical sensor. The optical sensor voltage regulator circuit includes an optical sensor and a compensation module. The optical sensor adopts a thin-film transistor structure. The receiving end of the compensation module is connected to the output end of the optical sensor to receive the output signal of the optical sensor. The output end of the compensation module is connected to the port of the optical sensor to send a compensation signal to the port of the optical sensor to increase the voltage of the output signal during the voltage rise phase of the output signal.

[0006] Optionally, the port is the control terminal of the optical sensor. The compensation module includes a first compensation unit and a first control unit. The input terminal of the first compensation unit is connected to the output terminal of the optical sensor to receive the output signal of the optical sensor, and the output terminal of the first compensation unit sends a control signal. The input terminal of the first control unit is connected to the output terminal of the first compensation unit, and the output terminal of the first control unit is connected to the control terminal of the optical sensor. The first control unit receives the control signal and generates a first compensation signal. The control terminal of the optical sensor receives the first compensation signal and increases the voltage of the output signal during the voltage rise phase of the output signal.

[0007] Optionally, the first compensation unit includes a storage capacitor, a first transistor, a first MOSFET, a first resistor, a second resistor, and a third resistor; the base of the first transistor is connected to the output terminal of the photosensitive sensor, the collector of the first transistor is connected to the first power supply terminal through the first resistor, and the emitter of the first transistor is grounded; the first MOSFET is a P-type MOSFET, the control terminal of the first MOSFET is connected to the first power supply terminal through the first resistor, the input terminal of the first MOSFET is connected to the first power supply terminal through the second resistor, and the output terminal of the first MOSFET is grounded through the third resistor; one end of the storage capacitor is connected to the output terminal of the photosensitive sensor, and the other end of the storage capacitor is connected to the third resistor. The third resistor is grounded; the output terminal of the first compensation unit is connected to the input terminal of the first MOSFET; the first control unit includes a second MOSFET, a first inductor, a first diode, and a first filter capacitor; the second MOSFET is an N-type MOSFET, the control terminal of the second MOSFET is connected to the output terminal of the first compensation unit, the input terminal of the second MOSFET is connected to the second power supply terminal, the output terminal of the second MOSFET is grounded through the first inductor, and the output terminal of the second MOSFET is also connected to the negative terminal of the first diode, and connected to the output terminal of the first control unit through the first diode; one end of the first filter capacitor is connected to the positive terminal of the first diode, and the other end of the first filter capacitor is grounded.

[0008] Optionally, the port is the input terminal of the optical sensor. The compensation module includes a first compensation unit and a second control unit. The input terminal of the first compensation unit is connected to the output terminal of the optical sensor to receive the output signal of the optical sensor, and the output terminal of the first compensation unit sends a control signal. The input terminal of the second control unit is connected to the output terminal of the first compensation unit, and the output terminal of the second control unit is connected to the input terminal of the optical sensor. The second control unit receives the control signal and generates a second compensation signal. The input terminal of the optical sensor receives the second compensation signal and increases the voltage of the output signal during the voltage rise phase of the output signal.

[0009] Optionally, the first compensation unit includes a storage capacitor, a first transistor, a first MOSFET, a first resistor, a second resistor, and a third resistor; the base of the first transistor is connected to the output terminal of the photosensitive sensor, the collector of the first transistor is connected to the first power supply terminal through the first resistor, and the emitter of the first transistor is grounded; the first MOSFET is a P-type MOSFET, the control terminal of the first MOSFET is connected to the first power supply terminal through the first resistor, the input terminal of the first MOSFET is connected to the first power supply terminal through the second resistor, and the output terminal of the first MOSFET is grounded through the third resistor; one end of the storage capacitor is connected to the output terminal of the photosensitive sensor, and the other end of the storage capacitor is connected to the third resistor. The third resistor is grounded; the output terminal of the first compensation unit is connected to the input terminal of the first MOSFET; the second control unit includes a third MOSFET, a second inductor, a second diode, and a second filter capacitor; the third MOSFET is a P-type MOSFET, the control terminal of the third MOSFET is connected to the output terminal of the first compensation unit, the input terminal of the third MOSFET is connected to the third power supply terminal through the second inductor, and the output terminal of the third MOSFET is grounded; the input terminal of the third MOSFET is also connected to the anode of the second diode, and is connected to the output terminal of the second control unit through the second diode; one end of the second filter capacitor is connected to the cathode of the second diode, and the other end of the second filter capacitor is grounded.

[0010] Optionally, the port is the output terminal of the optical sensor, and the compensation module includes a second compensation unit. The input terminal of the second compensation unit is connected to the output terminal of the optical sensor to receive the output signal of the optical sensor. The second compensation unit generates a corresponding third compensation signal according to the output signal. The output terminal of the second compensation unit is connected to the output terminal of the optical sensor to output the third compensation signal to the output terminal of the optical sensor, and increases the voltage of the output signal during the voltage rise phase of the output signal.

[0011] Optionally, the second compensation unit includes a fourth MOSFET, a second transistor, a third diode, a fourth resistor, and a fifth resistor. The base of the second transistor is connected to the output terminal of the photosensitive sensor through the fourth resistor, the collector of the second transistor is connected to the fourth power supply terminal through the fifth resistor, and the emitter of the second transistor is grounded. The fourth MOSFET is a P-type MOSFET. The control terminal of the fourth MOSFET is connected to the collector of the second transistor, the input terminal of the fourth MOSFET is connected to the output terminal of the photosensitive sensor, and the output terminal of the fourth MOSFET is connected to the output terminal of the second compensation unit. The anode of the third diode is connected to the collector of the second transistor, and the cathode of the third diode is connected to the output terminal of the second compensation unit.

[0012] Optionally, the optical sensor voltage regulator circuit includes a first compensation unit, a first control unit, a second control unit, a second compensation unit, and a selection unit. The input terminal of the first compensation unit is connected to the output terminal of the optical sensor to receive the output signal of the optical sensor, and the output terminal of the first compensation unit emits a control signal. The first compensation unit is connected to a first power supply terminal and operates when the first power supply terminal provides a power signal. The input terminal of the first control unit is connected to the output terminal of the first compensation unit, and the output terminal of the first control unit is connected to the control terminal of the optical sensor. The first control unit receives the control signal and generates a first compensation signal. The control terminal of the optical sensor receives the first compensation signal and increases the voltage of the output signal during the voltage rise phase of the output signal. The first control unit is connected to a second power supply terminal and operates when the second power supply terminal provides a power signal. The input terminal of the second control unit is connected to the output terminal of the first compensation unit, and the output terminal of the second control unit is connected to the input terminal of the optical sensor. The system is configured as follows: the second control unit receives the control signal and generates a second compensation signal; the input terminal of the optical sensor receives the second compensation signal and increases the voltage of the output signal during the voltage rise phase; the second control unit is connected to a third power supply terminal and operates when the third power supply terminal provides a power signal; the input terminal of the second compensation unit is connected to the output terminal of the optical sensor and receives the output signal of the optical sensor; the second compensation unit generates a corresponding third compensation signal based on the output signal; the output terminal of the second compensation unit is connected to the output terminal of the optical sensor and outputs the third compensation signal to the output terminal of the optical sensor, increasing the voltage of the output signal during the voltage rise phase; the second compensation unit is connected to a fourth power supply terminal and operates when the fourth power supply terminal provides a power signal; the selection unit is connected to at least the second power supply terminal, the third power supply terminal, and the fourth power supply terminal, and controls the second power supply terminal, the third power supply terminal, or the fourth power supply terminal to output a power signal.

[0013] This application also discloses a driving method for a light sensor, used in the light sensor voltage regulator circuit described above. The driving method for the light sensor includes the following steps: Acquire the output signal of the optical sensor; and A compensation signal is provided to the port of the optical sensor based on the output signal to increase the voltage of the output signal during the voltage rise phase of the output signal.

[0014] This application also discloses a display device, which includes a display panel and a light sensor voltage regulator circuit as described above, wherein the light sensor in the light sensor voltage regulator circuit is disposed on the display panel.

[0015] The beneficial effects of this application embodiment are as follows: This application embodiment sets up a light sensor voltage regulator circuit containing a light sensor and a compensation module. The compensation module receives the output signal of the light sensor and then generates a compensation signal based on the output signal of the light sensor. This increases the voltage of the output signal during the voltage rise phase of the output signal, avoiding the situation where the output of the light sensor using a thin-film transistor structure is unstable when it is first turned on or when the light sensor is affected by factors such as ambient temperature. This improves the output stability of the light sensor and enhances the dimming effect of the display screen. Attached Figure Description

[0016] The accompanying drawings, which form part of the specification, are used to provide a further understanding of the embodiments of this application and illustrate the implementation methods of this application, together with the textual description, to explain the principles of this application. Obviously, the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any creative effort. In the drawings: Figure 1 It is a curve trend graph of the output signal of an optical sensor; Figure 2 This is a schematic diagram of a voltage regulator circuit for an optical sensor provided in the first embodiment of this application; Figure 3 This is a schematic diagram of another optical sensor voltage regulator circuit provided in the first embodiment of this application; Figure 4 This is a schematic diagram of a first compensation unit provided in the first embodiment of this application; Figure 5 This is a waveform diagram of a control signal change provided in the first embodiment of this application; Figure 6 This is a schematic diagram of a first control unit provided in the first embodiment of this application; Figure 7 This is a schematic diagram of a photoelectric sensor voltage regulator circuit provided in the second embodiment of this application; Figure 8 This is a schematic diagram of a second control unit provided in the second embodiment of this application; Figure 9 This is a schematic diagram of the leakage current of an optical sensor under different input voltages according to the second embodiment of this application; Figure 10 This is a schematic diagram of a photoelectric sensor voltage regulator circuit provided in the third embodiment of this application; Figure 11 This is a schematic diagram of a second compensation unit provided in the third embodiment of this application; Figure 12 This is a schematic diagram of a photoelectric sensor voltage regulator circuit provided in the fourth embodiment of this application; Figure 13 This is a partial schematic diagram provided in the fourth embodiment of this application; Figure 14 This is a timing diagram provided in the fourth embodiment of this application; Figure 15 This is another timing diagram provided in the fourth embodiment of this application; Figure 16 This is a flowchart of a driving method for an optical sensor provided in the fifth embodiment of this application; Figure 17 This is a schematic diagram of a display device provided in the sixth embodiment of this application.

[0017] Wherein, 10 is a display device; 20 is a display panel; 30 is a light sensor voltage regulator circuit; 31 is a light sensor; 32 is a compensation module; Rx is a first voltage divider resistor; Ry is a second voltage divider resistor; 321 is a first compensation unit; Cst is a storage capacitor; Q1 is a first transistor; T1 is a first MOSFET; R1 is a first resistor; R2 is a second resistor; R3 is a third resistor; N1 is a first power supply terminal; 322 is a first control unit; T2 is a second MOSFET; L1 is a first inductor; D1 is a first diode; C1 is a first filter capacitor; N2 is a first filter capacitor; Second power supply terminal; 323, Second control unit; T3, Third MOSFET; L2, Second inductor; D2, Second diode; C2, Second filter capacitor; N3, Third power supply terminal; 324, Second compensation unit; T4, Fourth MOSFET; Q2, Second transistor; D3, Third diode; R4, Fourth resistor; R5, Fifth resistor; N4, Fourth power supply terminal; 33, Selection unit; 331, Timing controller; 332, First selection MOSFET; 333, Second selection MOSFET; 334, Third selection MOSFET; VCC, Power supply. Detailed Implementation

[0018] It should be understood that the terminology, specific structural and functional details used herein are merely for describing particular embodiments and are representative. However, this application may be implemented in many alternative forms and should not be construed as being limited to the embodiments set forth herein.

[0019] Furthermore, unless otherwise explicitly specified and limited, "connected" or "linked" should be interpreted broadly. For example, it can refer to a fixed connection, a detachable connection, or an integral connection; it can refer to a mechanical connection or an electrical connection; it can refer to a direct connection or an indirect connection through an intermediate medium, or a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0020] The present application will now be described in detail with reference to the accompanying drawings and optional embodiments.

[0021] like Figure 1 As shown, taking a thin-film transistor (TFT) optical sensor as an example when the display is powered on, even if the light intensity received by the optical sensor remains constant, the voltage of the optical sensor's output signal slowly increases. Furthermore, due to the influence of temperature and material properties, as well as factors such as the device manufacturing process, the voltage of the optical sensor's output signal will fluctuate. In practical applications, this manifests as a relatively lower output voltage during a cold start compared to the output voltage after a period of stable operation. These factors all contribute to unstable output from the optical sensor, affecting the dimming effect of the display.

[0022] To address the aforementioned issues, this application provides the following embodiments to improve the output stability of optical sensors.

[0023] like Figure 2 As shown, a photosensitive voltage regulator circuit 30 provided in the first embodiment of this application includes a photosensitive sensor 31 and a compensation module 32. The photosensitive sensor 31 adopts a thin-film transistor structure. The receiving end of the compensation module 32 is connected to the output end of the photosensitive sensor 31 to receive the output signal of the photosensitive sensor 31. The output end of the compensation module 32 is connected to the port of the photosensitive sensor 31 to send a compensation signal to the port of the photosensitive sensor 31 to increase the voltage of the output signal during the voltage rise phase of the output signal.

[0024] For ease of explanation, the output signal transmitted from the light sensor 31 to the compensation module 32 will be labeled as Vf, which can also be understood as a feedback signal; and the output signal transmitted from the light sensor 31 to the dimming circuit will be labeled as S_out. The dimming circuit dims the display panel according to the received output signal S_out.

[0025] This application embodiment includes a light sensor voltage regulator circuit 30 containing a light sensor 31 and a compensation module 32. The compensation module 32 receives the output signal of the light sensor 31 and then generates a compensation signal based on the output signal of the light sensor 31. This increases the voltage of the output signal during the voltage rise phase, avoiding unstable output of the light sensor 31, which uses a thin-film transistor structure, when it is first turned on or when it is affected by factors such as ambient temperature. This improves the output stability of the light sensor 31 and enhances the dimming effect of the display screen.

[0026] It should be noted that the voltage rise phase of the output signal can be the power-on phase or the phase after the power-on phase when the output signal of the optical sensor 31 fluctuates.

[0027] like Figure 2 As shown in this embodiment, the port of the optical sensor 31 is the control terminal of the optical sensor 31, and the compensation module 32 sends a compensation signal to the control terminal of the optical sensor 31 to improve the stability of the output signal of the optical sensor 31.

[0028] The compensation module 32 includes a first compensation unit 321 and a first control unit 322. Specifically, the input terminal of the first compensation unit 321 is connected to the output terminal of the light sensor 31 to receive the output signal Vf of the light sensor 31, and the output terminal of the first compensation unit 321 emits a control signal PWM.

[0029] The input terminal of the first control unit 322 is connected to the output terminal of the first compensation unit 321, and the output terminal of the first control unit 322 is connected to the control terminal of the optical sensor 31. The first control unit 322 receives the control signal PWM and generates a first compensation signal -V. The control terminal of the optical sensor 31 receives the first compensation signal -V and increases the voltage of the output signal during the voltage rise phase of the output signal Vf.

[0030] Since the control terminal voltage of the optical sensor 31 controls the current between the input and output terminals of the optical sensor 31 by changing the channel conductivity, thereby affecting the output voltage, this embodiment of the application achieves stable output of the optical sensor 31 during the power-on phase by issuing a first compensation signal -V to the control terminal of the optical sensor 31. Furthermore, the control terminal voltage of the optical sensor 31 rapidly regulates the channel carrier concentration through the electric field, requiring no current injection and exhibiting no inertial delay in response; moreover, the drain-source current I... DS With (V) GS -V th ) 2 Proportional, V GS Even a tiny change can lead to I DSThe output of the light sensor 31 can be quickly stabilized by sending a first compensation signal -V to the control terminal of the light sensor 31, as the output changes drastically.

[0031] In some embodiments, such as Figure 3 As shown, the photosensitive voltage regulator circuit 30 also includes a first voltage divider resistor Rx and a second voltage divider resistor Ry. The first end of the first voltage divider resistor Rx is connected to the output terminal of the photosensitive sensor 31, and the input terminal of the first compensation unit 321 is connected to the second end of the first voltage divider resistor Rx to receive the output signal Vf of the photosensitive sensor 31. One end of the second voltage divider resistor Ry is connected to the second end of the first voltage divider resistor Rx, and the other end of the second voltage divider resistor Ry is grounded. In this embodiment, the photocurrent is converted into voltage through the first voltage divider resistor Rx and the second voltage divider resistor Ry. Of course, in other embodiments, since the wiring in this application already has resistance, it is feasible to omit the first voltage divider resistor Rx and the second voltage divider resistor Ry, and the compensation module 32 can directly receive the output signal Vf of the photosensitive sensor 31.

[0032] In some embodiments, such as Figure 4 As shown, the first compensation unit 321 includes a storage capacitor Cst, a first transistor Q1, a first MOSFET T1, a first resistor R1, a second resistor R2, and a third resistor R3. The base of the first transistor Q1 is connected to the output terminal of the photosensitive sensor 31, the collector of the first transistor Q1 is connected to the first power supply terminal N1 through the first resistor R1, and the emitter of the first transistor Q1 is grounded. The first MOSFET T1 is a P-type MOSFET. The control terminal of the first MOSFET T1 is connected to the first power supply terminal N1 through the first resistor R1, the input terminal of the first MOSFET T1 is connected to the first power supply terminal N1 through the second resistor R2, and the output terminal of the first MOSFET T1 is grounded through the third resistor R3. One end of the storage capacitor Cst is connected to the output terminal of the photosensitive sensor 31, and the other end of the storage capacitor Cst is grounded through the third resistor R3. The output terminal of the first compensation unit 321 is connected to the input terminal of the first MOSFET T1.

[0033] When the output signal of the light sensor 31 is transmitted to the base of the first transistor Q1, the storage capacitor Cst is charged first (at this moment). Figure 4The upper end of the storage capacitor Cst is positive and the lower end is negative. When the storage capacitor Cst is charged to the conduction condition voltage of the first transistor Q1 (base voltage > emitter voltage), the collector and emitter of the first transistor Q1 are turned on. At this time, the first part of the power signal provided by the first power supply terminal N1 is grounded through the first resistor R1 and the first transistor Q1, the second part is provided to the control terminal of the first MOSFET T1, and the third part is provided to the input terminal of the first MOSFET T1 through the second resistor R2. After the power signal is divided, the voltage supplied to the control terminal of the first MOSFET T1 is small and is low, which makes the first MOSFET T1 turn on. The voltage received by the input terminal of the first MOSFET T1 is also low. At this time, the output terminal of the first compensation unit 321 outputs a low-level voltage.

[0034] Next, the output of the first MOSFET T1 charges the storage capacitor Cst (at this moment) Figure 4 (The lower end of the storage capacitor Cst is the positive terminal, and the upper end is the negative terminal). The base potential of the first transistor Q1 is pulled low, and the first transistor Q1 is cut off, disconnecting the collector and emitter of the first transistor Q1. At this time, the control terminal voltage of the first MOSFET T1 is the power supply voltage, which is a high-level voltage. The first MOSFET T1 is turned off, and the input terminal voltage of the first MOSFET T1 is a high-level voltage. That is, the output terminal of the first compensation unit 321 outputs a high-level voltage at this time.

[0035] Figure 5 This is a waveform diagram illustrating the change of a control signal. Through the aforementioned repetitive cycle, the control signal output by the first compensation unit 321 is a signal with alternating low and high levels, i.e., a PWM (Pulse Width Modulation) wave signal. Specifically, since the output signal voltage of the light sensor 31 gradually increases, when the output signal voltage of the light sensor 31 is low, the waveform of the PWM wave signal is as shown in square wave 1, where the high level accounts for a larger proportion, i.e., the PWM wave has a large duty cycle; when the output signal voltage of the light sensor 31 is high, the waveform of the PWM wave signal is as shown in square wave 2, where the high level accounts for a smaller proportion, i.e., the PWM wave has a small duty cycle. Therefore, as the output signal Vf of the light sensor 31 gradually increases, the duty cycle of the PWM wave gradually decreases.

[0036] like Figure 6As shown, the first control unit 322 includes a second MOSFET T2, a first inductor L1, a first diode D1, and a first filter capacitor C1. The second MOSFET T2 is an N-type MOSFET. The control terminal of the second MOSFET T2 is connected to the output terminal of the first compensation unit 321. The input terminal of the second MOSFET T2 is connected to the second power supply terminal N2. The output terminal of the second MOSFET T2 is grounded through the first inductor L1. The output terminal of the second MOSFET T2 is also connected to the negative terminal of the first diode D1, and is connected to the output terminal of the first control unit 322 through the first diode D1. One end of the first filter capacitor C1 is connected to the positive terminal of the first diode D1, and the other end of the first filter capacitor C1 is grounded.

[0037] In this embodiment, the first control unit 322 adopts a DC negative voltage conversion design (also known as a Buck-Boost circuit design). According to the Buck-Boost principle (the magnetoelectric conversion of the first inductor L1, combined with the PWM wave signal received by the second MOSFET T2, controls the turning on and off of the second MOSFET T2, and then supplies the first filter capacitor C1 with a charging and discharging process), the voltage output by the output terminal of the first control unit 322 is a negative voltage. The absolute value of this output voltage changes from low to high, and then to stable.

[0038] Based on the N-curve characteristics of the optical sensor 31, the first compensation signal -V controls the gate of the optical sensor 31. The smaller the voltage of the first compensation signal -V, the larger the output current of the optical sensor 31. Therefore, as the output signal Vf of the optical sensor 31 increases, the first compensation signal -V gradually decreases, and the output current of the optical sensor 31 increases under the action of the first compensation signal -V. This, combined with the gradually increasing photocurrent generated by the illumination of the optical sensor 31, keeps the overall output signal S_out of the optical sensor 31 stable.

[0039] According to Ohm's law, when the output voltage of the optical sensor 31 rises to a stable state, the voltage of the output signal Vf received by the first compensation unit 321 is stable, the duty cycle of the control signal PWM is stable, and the voltage of the first compensation signal -V is stable, thus achieving stable output of the optical sensor 31 during the power-on phase.

[0040] By employing the compensation module 32 design in this embodiment, regardless of whether it's during the power-on phase or later when the output voltage of the optical sensor 31 fluctuates, as long as the voltage of the output signal Vf of the optical sensor 31 fluctuates, the first compensation unit 321 and the first control unit 322 can immediately operate to stabilize the output signal Vf of the optical sensor 31. This process does not require additional design of the startup time and judgment method of the compensation module 32, avoiding programming. Moreover, once the output signal of the optical sensor 31 stabilizes, the first compensation unit 321 and the first control unit 322 will not affect the output signal of the optical sensor 31.

[0041] like Figure 7 As shown, the optical sensor voltage regulator circuit 30 provided as the second embodiment of this application differs from the first embodiment in that the port of the optical sensor 31 in this embodiment is its input terminal.

[0042] The compensation module 32 includes a first compensation unit 321 and a second control unit 323. The input terminal of the first compensation unit 321 is connected to the output terminal of the light sensor 31, and receives the output signal Vf of the light sensor 31. The output terminal of the first compensation unit 321 also sends a control signal PWM. The input terminal of the second control unit 323 is connected to the output terminal of the first compensation unit 321, and the output terminal of the second control unit 323 is connected to the input terminal of the light sensor 31. The second control unit 323 receives the control signal PWM and generates a second compensation signal +V. The input terminal of the light sensor 31 receives the second compensation signal +V and increases the voltage of the output signal during the voltage rise phase of the output signal.

[0043] This embodiment of the application improves the output stability of the light sensor 31 by providing a second compensation signal +V to the input terminal of the light sensor 31, without needing to adjust the voltage of the control terminal of the light sensor 31, thus reducing the complexity of the control terminal.

[0044] like Figure 4As shown, in some embodiments, the first compensation unit 321 includes a storage capacitor Cst, a first transistor Q1, a first MOSFET T1, a first resistor R1, a second resistor R2, and a third resistor R3; the base of the first transistor Q1 is connected to the output terminal of the photosensitive sensor 31, the collector of the first transistor Q1 is connected to the first power supply terminal N1 through the first resistor R1, and the emitter of the first transistor Q1 is grounded; the first MOSFET T1 is a P-type MOSFET, the control terminal of the first MOSFET T1 is connected to the first power supply terminal N1 through the first resistor R1, the input terminal of the first MOSFET T1 is connected to the first power supply terminal N1 through the second resistor R2, and the output terminal of the first MOSFET T1 is grounded through the third resistor R3; one end of the storage capacitor Cst is connected to the output terminal of the photosensitive sensor 31, and the other end of the storage capacitor Cst is grounded through the third resistor R3; the output terminal of the first compensation unit 321 is connected to the input terminal of the first MOSFET T1.

[0045] like Figure 8 As shown, the second control unit 323 includes a third MOSFET T3, a second inductor L2, a second diode D2, and a second filter capacitor C2. The third MOSFET T3 is a P-type MOSFET. The control terminal of the third MOSFET T3 is connected to the output terminal of the first compensation unit 321. The input terminal of the third MOSFET T3 is connected to the third power supply terminal N3 through the second inductor L2. The output terminal of the third MOSFET T3 is grounded. The input terminal of the third MOSFET T3 is also connected to the positive terminal of the second diode D2 and is connected to the output terminal of the second control unit 323 through the second diode D2. One end of the second filter capacitor C2 is connected to the negative terminal of the second diode D2, and the other end of the second filter capacitor C2 is grounded.

[0046] like Figure 5 As shown, when the output signal Vf of the light sensor 31 gradually increases, the control signal PWM becomes a PWM wave signal with a gradually decreasing duty cycle. In this embodiment, the second control unit 323 employs a DC boost converter module (also called a Boost circuit). Based on the Boost principle (the magnetoelectric conversion of the second inductor L2, combined with the control signal received by the third MOSFET T3, controls the conduction and turn-off of the third MOSFET T3, and then supplies the second filter capacitor C2 with charging and discharging), during the gradual increase of the output signal Vf of the light sensor 31, the voltage of the second compensation signal +V remains positive, and the voltage change trend of the second compensation signal +V is: from high to low, then to stable.

[0047] like Figure 9As shown, the horizontal axis represents light intensity, and the vertical axis represents the current output by the light sensor. The higher the voltage received at the input terminal of the light sensor 31, the higher the leakage current output by the light sensor 31. Since the output terminal of the second control unit 323 is connected to the input terminal of the light sensor 31, the output terminal of the second control unit 323 outputs a second compensation signal +V. When the voltage of the second compensation signal +V is higher, the leakage current output by the light sensor 31 is higher. Therefore, since the voltage of the output signal Vf of the light sensor 31 gradually increases, the duty cycle of the control signal PWM gradually decreases, and the voltage of the second compensation signal +V gradually decreases, the leakage current output by the light sensor 31 gradually decreases under the action of the second compensation signal +V. In addition, the leakage current generated by the light sensor 31 itself when exposed to light gradually increases, so that the overall leakage current output by the light sensor 31 remains stable.

[0048] According to Ohm's law, when the output signal Vf of the optical sensor 31 rises to a steady state, the waveform of the control signal PWM stabilizes, and the voltage of the second compensation signal +V stabilizes, thereby achieving stable output of the optical sensor 31.

[0049] like Figure 10 As shown, the third embodiment of the optical sensor voltage regulator circuit 30 provided in this application differs from the first embodiment in that, in this embodiment, the port of the optical sensor 31 is its output terminal, and the compensation module 32 includes a second compensation unit 324. The input terminal of the second compensation unit 324 is connected to the output terminal of the optical sensor 31 and receives the output signal Vf of the optical sensor 31. The second compensation unit 324 generates a corresponding third compensation signal Vd according to the output signal Vf. The output terminal of the second compensation unit 324 is connected to the output terminal of the optical sensor 31 and outputs the third compensation signal Vd to the output terminal of the optical sensor 31, and increases the voltage of the output signal during the voltage rise phase of the output signal.

[0050] This application embodiment improves the output stability of the light sensor 31 by providing a third compensation signal Vd to the output terminal of the light sensor 31. The output signal S_out received by the dimming circuit from the light sensor 31 is the sum of the third compensation signal Vd and the output signal Vf generated by the light sensor 31 under illumination. Adjusting the third compensation signal Vd can accurately affect the magnitude of the output signal S_out, which is beneficial to further improve the stability of the output signal S_out.

[0051] like Figure 11As shown, in some embodiments, the second compensation unit 324 includes a fourth MOSFET T4, a second transistor Q2, a third diode D3, a fourth resistor R4, and a fifth resistor R5. The base of the second transistor Q2 is connected to the output terminal of the photosensitive sensor 31 through the fourth resistor R4, and the collector of the second transistor Q2 is connected to the fourth power supply terminal N4 through the fifth resistor R5. The emitter of the second transistor Q2 is grounded. The fourth MOSFET T4 is a P-type MOSFET. The control terminal of the fourth MOSFET T4 is connected to the collector of the second transistor Q2, the input terminal of the fourth MOSFET T4 is connected to the output terminal of the photosensitive sensor 31, and the output terminal of the fourth MOSFET T4 is connected to the output terminal of the second compensation unit 324. The anode of the third diode D3 is connected to the collector of the second transistor Q2, and the cathode of the third diode D3 is connected to the output terminal of the second compensation unit 324.

[0052] Since the output signal Vf of the photosensitive sensor 31 gradually increases during the power-on phase, the output signal Vf is transmitted to the base of the second transistor Q2. The collector voltage Q2_out of the second transistor Q2 is Q2_out = V_N4 * [R_Q2 / (R5 + R_Q2)], where R_Q2 is the on-resistance between the collector and emitter of the second transistor Q2. As the conduction state of the collector and emitter of the second transistor Q2 increases with the increase of the output signal Vf, R_Q2 gradually decreases, and the third compensation signal Vd = Q2_out - V_D3 is directly output through the third diode D3. When Q2_out is low or 0V, the fourth MOSFET T4 is turned on due to the decrease in gate voltage, and the output signal Vf is normally output through the fourth MOSFET T4. At this time, the third diode D3 is turned off due to the decrease in the collector voltage Q2_out of the second transistor Q2.

[0053] When the output signal Vf is small, the second transistor Q2 and the fourth MOSFET T4 are disconnected. The power supply voltage V_N4 provided by the fourth power supply terminal N4 is output through the third diode D3 to form the third compensation signal Vd. At this time, the voltage of the third compensation signal Vd is relatively large. When the output signal Vf is large, the second transistor Q2 is turned on, the collector voltage Q2_out of the second transistor Q2 decreases, the fourth MOSFET T4 is turned on, the third diode D3 is turned off, and the output signal Vf is output to the output terminal of the photosensitive sensor 31 through the fourth MOSFET T4.

[0054] like Figure 12 and Figure 13As shown, the optical sensor voltage regulator circuit 30 provided in the fourth embodiment of this application differs from the first embodiment in that the port of the optical sensor 31 in this embodiment is its input terminal, output terminal and control terminal, that is, the compensation module 32 is connected to the input terminal, output terminal and control terminal of the optical sensor 31 at the same time.

[0055] Specifically, the optical sensor voltage regulator circuit 30 includes a first compensation unit 321, a first control unit 322, a second control unit 323, a second compensation unit 324, and a selection unit 33. The input terminal of the first compensation unit 321 is connected to the output terminal of the optical sensor 31 and receives the output signal Vf of the optical sensor 31. The output terminal of the first compensation unit 321 emits a control signal PWM. The first compensation unit 321 is connected to the first power supply terminal N1 and operates when the first power supply terminal N1 provides a power signal.

[0056] The input terminal of the first control unit 322 is connected to the output terminal of the first compensation unit 321, and the output terminal of the first control unit 322 is connected to the control terminal of the optical sensor 31. The first control unit 322 receives the control signal PWM and generates a first compensation signal -V. The control terminal of the optical sensor 31 receives the first compensation signal -V and increases the voltage of the output signal during the voltage rise phase of the output signal. The first control unit 322 is connected to the second power supply terminal N2 and operates when the second power supply terminal N2 provides a power signal.

[0057] The input terminal of the second control unit 323 is connected to the output terminal of the first compensation unit 321, and the output terminal of the second control unit 323 is connected to the input terminal of the light sensor 31. The second control unit 323 receives the control signal PWM and generates a second compensation signal +V. The input terminal of the light sensor 31 receives the second compensation signal +V and increases the voltage of the output signal during the voltage rise phase. The second control unit 323 is connected to the third power supply terminal N3 and operates when the third power supply terminal N3 provides a power signal.

[0058] The input terminal of the second compensation unit 324 is connected to the output terminal of the optical sensor 31, and receives the output signal Vf of the optical sensor 31. The second compensation unit 324 generates a corresponding third compensation signal Vd according to the output signal Vf. The output terminal of the second compensation unit 324 is connected to the output terminal of the optical sensor 31, and outputs the third compensation signal Vd to the output terminal of the optical sensor 31, and increases the voltage of the output signal during the voltage rise phase. The second compensation unit 324 is connected to the fourth power supply terminal N4 and operates when the fourth power supply terminal N4 provides a power signal.

[0059] The selection unit 33 is connected to at least the second power terminal N2, the third power terminal N3, and the fourth power terminal N4, and controls the second power terminal N2, the third power terminal N3, or the fourth power terminal N4 to output a power signal.

[0060] This embodiment, combining the designs of embodiments one to three above, connects the compensation module 32 simultaneously to the input, output, and control terminals of the optical sensor 31. It can compensate for the input, output, or control terminals of the optical sensor 31 as needed, improving the output stability of the optical sensor 31. Since this embodiment has three optional compensation circuits—namely, the first compensation unit 321 and the first control unit 322, the first compensation unit 321 and the second control unit 323, and the second compensation unit 324—if one compensation circuit malfunctions, the others can be replaced, thereby improving the overall reliability of the optical sensor voltage regulator circuit 30.

[0061] like Figure 13 As shown, in some embodiments, the selection unit 33 includes a timing controller 331, a first selection MOSFET 332, a second selection MOSFET 333, and a third selection MOSFET 334. The input terminals of the first selection MOSFET 332, the second selection MOSFET 333, and the third selection MOSFET 334 are all connected to the power supply VCC. The control terminals of the first selection MOSFET 332, the second selection MOSFET 333, and the third selection MOSFET 334 are all connected to the timing controller 331. The output terminal of the first selection MOSFET 332 is connected to the second power supply terminal N2 to receive a first selection signal. The output terminal of the second selection MOSFET 333 is connected to the third power supply terminal N3 to receive a second selection signal. The output terminal of the third selection MOSFET 334 is connected to the fourth power supply terminal N4 to receive a third selection signal.

[0062] In some embodiments, the first selection MOSFET 332, the second selection MOSFET 333, and the third selection MOSFET 334 are all N-type MOSFETs. The timing controller 331 can only control one N-type MOSFET to turn on at a time, and the three N-type MOSFETs can select which output to use based on their turn-on time. The timing control module can be configured as a simple programmable controller, capable of outputting corresponding waveforms according to program settings.

[0063] like Figure 14As shown, in a specific implementation, when the program is set to 100 (binary mode), I / O_1=H, indicating that the first selection signal is high; I / O_2=L, indicating that the second selection signal is low; and I / O_3=L, indicating that the third selection signal is low. At this time, the first selection MOSFET 332 is turned on, the second power supply terminal N2 provides a power signal, and the first compensation unit 321 and the first control unit 322 operate together, outputting the first compensation signal -V. If other branches need to operate, they can be set to 010 and 001 respectively, causing the second selection MOSFET 333 or the third selection MOSFET 334 to turn on.

[0064] like Figure 15 As shown, in another specific implementation, the three compensation schemes operate alternately. When the program is set to 100 (binary mode), I / O_1=H, indicating that the first selection signal is high; I / O_2=L, indicating that the second selection signal is low; and I / O_3=L, indicating that the third selection signal is low. When the program is set to 010 (binary mode), I / O_1=L, indicating that the first selection signal is low; I / O_2=L, indicating that the second selection signal is low; and I / O_3=H, indicating that the third selection signal is high. When the program is set to 001 (binary mode), I / O_1=L, indicating that the first selection signal is low; I / O_2=H, indicating that the second selection signal is high; and I / O_3=L, indicating that the third selection signal is low. When the program is continuously set to repeat 100, 010, and 001, the output waveform is as follows. Figure 15 As shown, at this time, the first selection MOSFET 332, the third selection MOSFET 334, and the second selection MOSFET 333 are turned on alternately, thereby controlling the three compensation schemes to work alternately.

[0065] In some embodiments, the port of the optical sensor 31 can also be its input and output terminals. The compensation module 32 is connected to both the input and output terminals of the optical sensor 31 and provides compensation signals to the input or output terminals of the optical sensor 31 as needed to improve the output stability of the optical sensor 31.

[0066] In some embodiments, the port of the optical sensor 31 can also be its input terminal and control terminal. The compensation module 32 is connected to both the input terminal and the control terminal of the optical sensor 31. It provides compensation signals to the input terminal or control terminal of the optical sensor 31 as needed to improve the output stability of the optical sensor 31.

[0067] In some embodiments, the port of the optical sensor 31 can also be its output terminal and control terminal. The compensation module 32 is connected to both the output terminal and the control terminal of the optical sensor 31. It provides compensation signals to the output terminal or control terminal of the optical sensor 31 as needed to improve the output stability of the optical sensor 31.

[0068] like Figure 16 As shown, a method for driving a light sensor is provided as a fifth embodiment of this application. This method is used in the light sensor voltage regulator circuit described above, and includes the following steps: S1: Acquire the output signal of the optical sensor; S2: Provide a compensation signal to the port of the optical sensor according to the output signal to increase the voltage of the output signal during the voltage rise phase of the output signal.

[0069] In some embodiments, the port of the optical sensor is its control terminal, as detailed in the design of the first embodiment.

[0070] In some embodiments, the port of the optical sensor is its input terminal, as detailed in the design of the second embodiment.

[0071] In some embodiments, the port of the optical sensor is its output terminal, as detailed in the design of the third embodiment.

[0072] In some embodiments, the ports of the optical sensor are its input terminal, output terminal, and control terminal, as detailed in the design of the fourth embodiment.

[0073] like Figure 17 As shown, as a display device provided in the sixth embodiment of this application, the display device 10 includes a display panel 20 and a light sensor voltage regulator circuit 30 as described above, wherein the light sensor 31 in the light sensor voltage regulator circuit 30 is disposed on the display panel 20.

[0074] It should be noted that the limitations of each step involved in this solution are not considered as limiting the order of steps, provided that they do not affect the implementation of the specific solution. The steps listed first can be executed first, later, or even simultaneously. Solutions from different embodiments can be combined and applied without conflict. As long as this solution can be implemented, they should be considered to fall within the protection scope of this application.

[0075] The above description, in conjunction with specific optional embodiments, provides a further detailed explanation of this application and should not be construed as limiting the specific implementation of this application to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of this application, and all such modifications or substitutions should be considered within the scope of protection of this application.

Claims

1. A voltage regulator circuit for an optical sensor, characterized in that, include: An optical sensor, wherein the optical sensor employs a thin-film transistor structure; as well as A compensation module, wherein the receiving end of the compensation module is connected to the output end of the optical sensor, and receives the output signal of the optical sensor; The output terminal of the compensation module is connected to the port of the optical sensor, and sends a compensation signal to the port of the optical sensor to increase the voltage of the output signal during the voltage rise phase of the output signal.

2. The optical sensor voltage regulator circuit as described in claim 1, characterized in that, The port is the control terminal of the optical sensor. The compensation module includes a first compensation unit and a first control unit. The input terminal of the first compensation unit is connected to the output terminal of the optical sensor to receive the output signal of the optical sensor. The output terminal of the first compensation unit sends out a control signal. The input terminal of the first control unit is connected to the output terminal of the first compensation unit, and the output terminal of the first control unit is connected to the control terminal of the optical sensor. The first control unit receives the control signal and generates a first compensation signal; the control terminal of the optical sensor receives the first compensation signal and increases the voltage of the output signal during the voltage rise phase of the output signal.

3. The optical sensor voltage regulator circuit as described in claim 2, characterized in that, The first compensation unit includes a storage capacitor, a first transistor, a first MOSFET, a first resistor, a second resistor, and a third resistor. The base of the first transistor is connected to the output terminal of the photosensitive sensor, the collector of the first transistor is connected to the first power supply terminal through the first resistor, and the emitter of the first transistor is grounded. The first MOSFET is a P-type MOSFET. The control terminal of the first MOSFET is connected to the first power supply terminal through the first resistor, the input terminal of the first MOSFET is connected to the first power supply terminal through the second resistor, and the output terminal of the first MOSFET is grounded through the third resistor. One end of the storage capacitor is connected to the output terminal of the photosensitive sensor, and the other end of the storage capacitor is grounded through the third resistor. The output terminal of the first compensation unit is connected to the input terminal of the first MOSFET. The first control unit includes a second MOSFET, a first inductor, a first diode, and a first filter capacitor. The second MOSFET is an N-type MOSFET. The control terminal of the second MOSFET is connected to the output terminal of the first compensation unit, the input terminal of the second MOSFET is connected to the second power supply terminal, the output terminal of the second MOSFET is grounded through the first inductor, and the output terminal of the second MOSFET is also connected to the negative terminal of the first diode, which is connected to the output terminal of the first control unit. One end of the first filter capacitor is connected to the positive terminal of the first diode, and the other end of the first filter capacitor is grounded.

4. The optical sensor voltage regulator circuit as described in claim 1, characterized in that, The port is the input terminal of the optical sensor. The compensation module includes a first compensation unit and a second control unit. The input terminal of the first compensation unit is connected to the output terminal of the optical sensor to receive the output signal of the optical sensor. The output terminal of the first compensation unit sends out a control signal. The input terminal of the second control unit is connected to the output terminal of the first compensation unit, and the output terminal of the second control unit is connected to the input terminal of the optical sensor. The second control unit receives the control signal and generates a second compensation signal; the input terminal of the optical sensor receives the second compensation signal and increases the voltage of the output signal during the voltage rise phase of the output signal.

5. The optical sensor voltage regulator circuit as described in claim 4, characterized in that, The first compensation unit includes a storage capacitor, a first transistor, a first MOSFET, a first resistor, a second resistor, and a third resistor. The base of the first transistor is connected to the output terminal of the photosensitive sensor, the collector of the first transistor is connected to the first power supply terminal through the first resistor, and the emitter of the first transistor is grounded. The first MOSFET is a P-type MOSFET. The control terminal of the first MOSFET is connected to the first power supply terminal through the first resistor, the input terminal of the first MOSFET is connected to the first power supply terminal through the second resistor, and the output terminal of the first MOSFET is grounded through the third resistor. One end of the storage capacitor is connected to the output terminal of the photosensitive sensor, and the other end of the storage capacitor is grounded through the third resistor. The output terminal of the first compensation unit is connected to the input terminal of the first MOSFET. The second control unit includes a third MOSFET, a second inductor, a second diode, and a second filter capacitor. The third MOSFET is a P-type MOSFET. The control terminal of the third MOSFET is connected to the output terminal of the first compensation unit. The input terminal of the third MOSFET is connected to the third power supply terminal through the second inductor. The output terminal of the third MOSFET is grounded. The input terminal of the third MOSFET is also connected to the anode of the second diode and is connected to the output terminal of the second control unit through the second diode. One end of the second filter capacitor is connected to the cathode of the second diode, and the other end of the second filter capacitor is grounded.

6. The optical sensor voltage regulator circuit as described in claim 1, characterized in that, The port is the output terminal of the optical sensor. The compensation module includes a second compensation unit. The input terminal of the second compensation unit is connected to the output terminal of the optical sensor to receive the output signal of the optical sensor. The second compensation unit generates a corresponding third compensation signal according to the output signal. The output terminal of the second compensation unit is connected to the output terminal of the optical sensor to output the third compensation signal to the output terminal of the optical sensor, and increases the voltage of the output signal during the voltage rise phase of the output signal.

7. The optical sensor voltage regulator circuit as described in claim 6, characterized in that, The second compensation unit includes a fourth MOSFET, a second transistor, a third diode, a fourth resistor, and a fifth resistor. The base of the second transistor is connected to the output terminal of the photosensitive sensor through the fourth resistor, the collector of the second transistor is connected to the fourth power supply terminal through the fifth resistor, and the emitter of the second transistor is grounded. The fourth MOSFET is a P-type MOSFET. The control terminal of the fourth MOSFET is connected to the collector of the second transistor, the input terminal of the fourth MOSFET is connected to the output terminal of the photosensitive sensor, and the output terminal of the fourth MOSFET is connected to the output terminal of the second compensation unit. The anode of the third diode is connected to the collector of the second transistor, and the cathode of the third diode is connected to the output terminal of the second compensation unit.

8. The optical sensor voltage regulator circuit as described in claim 1, characterized in that, The optical sensor voltage regulator circuit includes: The first compensation unit has its input terminal connected to the output terminal of the optical sensor to receive the output signal of the optical sensor, and its output terminal emits a control signal; the first compensation unit is connected to a first power supply terminal and operates when the first power supply terminal provides a power signal. A first control unit, the input terminal of which is connected to the output terminal of the first compensation unit, and the output terminal of which is connected to the control terminal of the optical sensor; the first control unit receives the control signal and generates a first compensation signal; the control terminal of the optical sensor receives the first compensation signal and increases the voltage of the output signal during the voltage rise phase of the output signal; the first control unit is connected to a second power supply terminal and operates when the second power supply terminal provides a power signal; A second control unit is connected to the input of the first compensation unit and to the input of the optical sensor. The second control unit receives the control signal and generates a second compensation signal. The input of the optical sensor receives the second compensation signal and increases the voltage of the output signal during the voltage rise phase. The second control unit is connected to a third power supply and operates when the third power supply provides a power signal. A second compensation unit, the input terminal of which is connected to the output terminal of the optical sensor, receives the output signal of the optical sensor, and generates a corresponding third compensation signal based on the output signal; the output terminal of the second compensation unit is connected to the output terminal of the optical sensor, outputs the third compensation signal to the output terminal of the optical sensor, and increases the voltage of the output signal during the voltage rise phase; the second compensation unit is connected to a fourth power supply terminal and operates when the fourth power supply terminal provides a power signal; and The selection unit is connected to at least the second power supply terminal, the third power supply terminal, and the fourth power supply terminal, and controls the second power supply terminal, the third power supply terminal, or the fourth power supply terminal to output a power signal.

9. A driving method for an optical sensor, used in the optical sensor voltage regulator circuit as described in any one of claims 1-8, characterized in that, Including the following steps: Acquire the output signal of the optical sensor; and A compensation signal is provided to the port of the optical sensor based on the output signal to increase the voltage of the output signal during the voltage rise phase of the output signal.

10. A display device, characterized in that, It includes a display panel and a light sensor voltage regulator circuit as described in any one of claims 1-8, wherein the light sensor in the light sensor voltage regulator circuit is disposed on the display panel.

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