Ambient light detection circuit and detection method, display device

Abstract

The present disclosure relates to the technical field of display, and provides an ambient light detection circuit and method, and a display device. The ambient light detection circuit is used for ambient light detection of a display panel. The detection circuit comprises: a plurality of sensing modules, which are used for collecting ambient light and outputting current sensing signals based on the ambient light; a plurality of current conversion modules, which are arranged correspondingly to the plurality of sensing modules, and are used for converting the current sensing signals output by the sensing modules connected thereto into voltage sensing signals; a plurality of storage modules, which are arranged correspondingly to the plurality of current conversion modules, and are used for storing the voltage sensing signals output by the current conversion modules connected thereto in response to a sampling control signal; and a control module, which is connected to the storage modules respectively, and is used for synchronously outputting the sampling control signal to each of the storage modules.

Description

Technical Field

[0001] This disclosure relates to the field of display technology, and more specifically, to an ambient light detection circuit and detection method, and a display device. Background Technology

[0002] With the development of display technology, display devices can perform more and more functions. For example, display devices can automatically collect ambient light and adjust the display color temperature and brightness according to the ambient light. However, in related technologies, sensing devices used to detect ambient light suffer from signal asynchrony.

[0003] It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0004] The purpose of this disclosure is to overcome the shortcomings of the prior art and provide an ambient light detection circuit, detection method, and display device.

[0005] According to one aspect of this disclosure, an ambient light detection circuit is provided for detecting ambient light on a display panel. The detection circuit includes: a plurality of sensing modules, each sensing module being used to collect ambient light and output a current sensing signal based on the ambient light; a plurality of current conversion modules, corresponding to the plurality of sensing modules, each current conversion module being used to convert the current sensing signal output by the sensing modules connected thereto into a voltage sensing signal; a plurality of storage modules, corresponding to the plurality of current conversion modules, each storage module being used to store the voltage sensing signal output by the current conversion modules connected thereto in response to a sampling control signal; and a control module, respectively connected to the storage modules, the control module being used to synchronously output the sampling control signal to each of the storage modules.

[0006] In an exemplary embodiment of this disclosure, the detection circuit further includes: a gating module connected in series between the storage module and the control module, the gating module being used to conduct a connection path between the corresponding storage module and the control module in response to a gating control signal output by the control module; an analog-to-digital converter module connected in series between the gating module and the control module, the analog-to-digital converter module being used to convert the acquired voltage sensing signal into a digital voltage signal for output; and a level conversion module connected to the control module, the level conversion module being used to convert the sampling control signal into a corresponding level signal for output.

[0007] In an exemplary embodiment of this disclosure, the current conversion module includes: a signal amplification unit, one input terminal connected to a reference voltage terminal and the other input terminal connected to the output terminal of a corresponding sensing module; a gain adjustment unit, one end connected to the output terminal of the corresponding sensing module and the other end connected to the output terminal of the signal amplification unit, the gain adjustment unit being used to determine the voltage sensing signal according to a selected gain coefficient; and a feedback unit connected in parallel across the two ends of the gain adjustment unit, the feedback unit being used to prevent the signal amplification unit from self-oscillating.

[0008] In an exemplary embodiment of this disclosure, the gain adjustment unit includes multiple parallel gain branches, each gain branch including: a gain resistor; and a gain control switch connected in series with the gain resistor. The gain control switch is used to turn on the corresponding gain branch in response to a gain control signal output by the control module to adjust the gain coefficient of the gain adjustment unit. The feedback unit includes: a feedback capacitor connected in parallel across the two ends of the gain branch. The signal amplification unit includes: an operational amplifier, one input terminal of which is connected to the reference voltage terminal, and the other input terminal of which is connected to the output terminal of the corresponding sensing module.

[0009] In an exemplary embodiment of this disclosure, the ratio of the on-resistance of the gain control switch to the gain resistor connected thereto is less than or equal to 1%.

[0010] In an exemplary embodiment of this disclosure, the ratio of the leakage current of the gain control switch to the induced current of the sensing module connected thereto is less than or equal to 1%.

[0011] In an exemplary embodiment of this disclosure, gain branches with the same gain coefficient in different current conversion modules reuse the same gain control signal; the conduction levels of the gain control signals corresponding to gain branches with different gain coefficients do not overlap.

[0012] In an exemplary embodiment of this disclosure, during the acquisition of an optical signal according to any gain coefficient, the on-level of the sampling control signal and the on-level of the gain control signal at least partially overlap, and the start time of the on-level of the sampling control signal is later than the start time of the on-level of the gain control signal.

[0013] In an exemplary embodiment of this disclosure, the gain adjustment unit includes a first gain branch, a second gain branch, a third gain branch, and a fourth gain branch, wherein the resistance values ​​of the gain resistors in the first gain branch, the second gain branch, the third gain branch, and the fourth gain branch increase sequentially.

[0014] In an exemplary embodiment of this disclosure, the storage module includes: a filtering unit connected between the corresponding operational amplifier and the gating module; and a sampling switch connected in series between the filtering unit and the corresponding operational amplifier, wherein the control terminal of the sampling switch receives the sampling control signal; wherein the sampling switch, in response to the sampling control signal, transmits the voltage sensing signal output by the current conversion module connected to it to the filtering unit for storage.

[0015] In an exemplary embodiment of this disclosure, the filtering unit includes: a filtering resistor, one end of which is connected to a first terminal of the filtering unit and the other end of which is connected to a second terminal of the filtering unit; and a storage capacitor, one end of which is connected to the second terminal of the filtering unit and the other end of which is grounded.

[0016] In an exemplary embodiment of this disclosure, the gating module includes: a plurality of gating switches, each of which is configured in a one-to-one correspondence with a plurality of storage modules; the control terminal of each gating switch receives a gating control signal; wherein the ratio of the time constant formed by the turn-off resistor of any gating switch and the storage capacitor to one sampling period is greater than or equal to 10 / n, where n is the number of gain branches included in the current conversion module, and n is a positive integer greater than or equal to 1.

[0017] In an exemplary embodiment of this disclosure, the control module is further configured to: acquire digital voltage signals corresponding to the voltage sensing signals output by each gain branch; and filter out digital voltage signals within a preset voltage range as valid voltage signals.

[0018] In an exemplary embodiment of this disclosure, the plurality of sensing modules include a first sensing module, a second sensing module, a third sensing module, and a fourth sensing module. The first sensing module is used to sense ambient red light, the second sensing module is used to sense ambient green light, the third sensing module is used to sense ambient blue light, and the fourth sensing module is used to sense white light.

[0019] According to a second aspect of this disclosure, an ambient light detection method is also provided, applied to the ambient light detection circuit described in any embodiment of this disclosure. The method is executed by a control module, and includes: controlling each current conversion module to be synchronously turned on within a sampling period; synchronously outputting a sampling control signal of the conduction level to each storage module during the conduction duration of the current conversion module, so as to control each storage module to store the voltage sensing signal output by the current conversion module connected to it; acquiring the voltage sensing signal stored in each storage module respectively, and preprocessing each voltage sensing signal.

[0020] In an exemplary embodiment of this disclosure, the method includes: controlling each current conversion module to be synchronously turned on within a sampling period; synchronously outputting a sampling control signal to each storage module during the on-time of the current conversion module to control each storage module to store the voltage sensing signal output by the current conversion module connected to it; outputting a gating control signal to the gating module to transmit the voltage sensing signal stored in the corresponding storage module to the analog-to-digital conversion module, the analog-to-digital conversion module being used to convert the acquired voltage sensing signal into a digital voltage signal; filtering the digital voltage signal; and if the digital voltage signal is a valid voltage signal, saving the valid voltage signal.

[0021] In an exemplary embodiment of this disclosure, the method includes: outputting a gain control signal in a time-division multiplexing manner according to a preset timing sequence within a sampling period to turn on each gain branch in a time-division multiplexing manner; after a preset duration of outputting the gain control signal with the turn-on level, synchronously outputting a sampling control signal with the turn-on level to each storage module to control each storage module to store the voltage sensing signal output by the current conversion module connected to it, wherein the turn-on level of the sampling control signal and the turn-on level of the gain control signal at least partially overlap; outputting a gating control signal to the gating module to transmit the voltage sensing signal stored in the corresponding storage module to the analog-to-digital conversion module, wherein the analog-to-digital conversion module converts the acquired voltage sensing signal into a digital voltage signal; filtering the digital voltage signal; and if the digital voltage signal is a valid voltage signal, saving the valid voltage signal.

[0022] According to a third aspect of this disclosure, a display device is also provided, including the ambient light detection circuit described in any embodiment of this disclosure.

[0023] The ambient light detection circuit disclosed herein includes an ambient light detection circuit in which each sensing module outputs a current sensing signal based on the collected ambient light. The corresponding current conversion module converts the current sensing signal into a corresponding voltage sensing signal and outputs it to the storage module connected to it. The control module controls the synchronous conduction of each storage module by synchronously outputting a sampling control signal to each storage module. Thus, each storage module can synchronously store the ambient light signal collected by the corresponding sensing module at the same time, thereby realizing synchronous acquisition by each sensing module and solving the problem of asynchronous light signals of different sensing modules in related technologies.

[0024] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Attached Figure Description

[0025] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure. It is obvious that the drawings described below are merely some embodiments of this disclosure, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0026] Figure 1 This is a structural block diagram of an environmental detection circuit according to one embodiment of the present disclosure;

[0027] Figure 2 This is a structural block diagram of an ambient light detection circuit according to another embodiment of the present disclosure;

[0028] Figure 3 This is a schematic diagram of an ambient light detection circuit according to one embodiment of the present disclosure;

[0029] Figure 4 This is a timing diagram of the control signal for one sampling period according to an embodiment of the present disclosure;

[0030] Figure 5 This is a flowchart of an ambient light detection method according to an embodiment of the present disclosure. Detailed Implementation

[0031] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, they are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and therefore detailed descriptions of them will be omitted. Furthermore, the drawings are merely illustrative of this disclosure and are not necessarily drawn to scale.

[0032] Although relative terms such as "up" and "down" are used in this specification to describe the relative relationship of one component of an icon to another, these terms are used only for convenience, such as according to the orientation of the examples shown in the accompanying drawings. It is understood that if the device of the icon is flipped upside down, the component described as "up" will become the component described as "down." When a structure is "up" of another structure, it may mean that the structure is integrally formed on the other structure, or that the structure is "directly" mounted on the other structure, or that the structure is "indirectly" mounted on the other structure through another structure.

[0033] The terms “a,” “one,” “the,” “the,” and “at least one” are used to indicate the presence of one or more elements / components / etc.; the terms “including” and “having” are used to indicate an open-ended inclusion and to mean that there may be other elements / components / etc. in addition to the listed elements / components / etc.; the terms “first,” “second,” and “third,” etc., are used only as markers and are not a limitation on the number of objects.

[0034] Figure 1 This is a structural block diagram of an ambient light detection circuit according to an embodiment of the present disclosure. This ambient light detection circuit can be used to detect ambient light on a display panel, such as... Figure 1 As shown, the detection circuit may include: multiple sensing modules 10, multiple current conversion modules 20, multiple storage modules 30, and a control module 40. The sensing modules 10 can collect ambient light and output a current sensing signal Id based on the ambient light. The multiple current conversion modules 20 are correspondingly arranged with the multiple sensing modules 10, and are used to convert the current sensing signal Id output by the sensing modules 10 connected to them into a voltage sensing signal Vs. The multiple storage modules 30 are correspondingly arranged with the multiple current conversion modules 20, and are used to store the voltage sensing signal Vs output by the current conversion modules 20 connected to them in response to the sampling control signal SMPL. The control module 40 is connected to the storage modules 30, and is used to synchronously output the sampling control signal SMPL to each storage module 30.

[0035] The ambient light detection circuit provided in this disclosure has a current sensing signal Id output by each sensing module 10 based on the collected ambient light. The corresponding current conversion module 20 converts the current sensing signal Id into a corresponding voltage sensing signal Vs and outputs it to the storage module 30 connected to it. The control module 40 controls the synchronous conduction of each storage module 30 by synchronously outputting a sampling control signal SMPL to each storage module 30. Thus, each storage module 30 can synchronously store the ambient light signal collected by the corresponding sensing module 10 at the same time, thereby realizing the synchronous acquisition of each sensing module 10 and solving the problem of asynchronous light signals of different sensing modules 10 in related technologies.

[0036] like Figure 1As shown, in an exemplary embodiment, the detection circuit may further include a gating module 50, an analog-to-digital converter module 60, and a level conversion module 70. The gating module 50 is connected in series between the storage module 30 and the control module 40, and can be used to conduct the connection path between the corresponding storage module 30 and the analog-to-digital converter module 60 in response to the gating control signal MX output by the control module 40. The analog-to-digital converter module 60 is connected in series between the gating module 50 and the control module 40, and can be used to convert the acquired voltage sensing signal Vs into a digital voltage signal Vd for output. The level conversion module 70 is connected to the control module 40, and can be used to convert the sampling control signal SMPL and the gating control signal MX into corresponding level signals for output.

[0037] Figure 2 Here is a structural block diagram of an ambient light detection circuit according to another embodiment of this disclosure, such as Figure 2 As shown, in an exemplary embodiment, the gating module 50 may include multiple gating switches MUX, such as transistor switches. The number of gating switches MUX can correspond one-to-one with the number of storage modules 30, that is, one gating switch MUX is connected to one storage module 30. When the storage module 30 is turned on, the voltage sensing signal Vs stored in the connected storage module 30 can be transmitted to the analog-to-digital converter module 60. For example, the storage modules 30 may include a first storage module 31 to a fourth storage module 34, and the gating module 50 may include a first gating switch MUX1 to a fourth gating switch MUX4. The first gating switch MUX1 is connected between the first storage module 31 and the analog-to-digital converter module 60, the second gating switch MUX2 is connected between the second storage module 32 and the analog-to-digital converter module 60, the third gating switch MUX3 is connected between the third storage module 33 and the analog-to-digital converter module 60, and the fourth gating switch MUX4 is connected between the fourth storage module 34 and the analog-to-digital converter module 60. When the first gating switch MUX1 is turned on, the voltage sensing signal Vs stored in the first storage module 31 can be transmitted to the analog-to-digital converter module 60. When the second gating switch MUX2 is turned on, the voltage sensing signal Vs stored in the second storage module 32 can be transmitted to the analog-to-digital converter module 60. And so on. The control module 40 outputs gating control signals MX in sequence so that the analog-to-digital converter module 60 can obtain the voltage sensing signals Vs of each storage module 30 respectively.

[0038] The current sensing signal Id output by each sensing module 10 is converted into a corresponding voltage sensing signal Vs by the current conversion module 20. The control module 40 then outputs a sampling control signal SMPL to each storage module 30 to establish a connection between the storage module 30 and the corresponding current conversion module 20. This allows the voltage sensing signal Vs output by the current conversion module 20 to be transmitted to the storage module 30 for storage. The control module 40 further outputs a gating control signal MX to control the gating module 50 to sequentially connect the storage module 30 and the analog-to-digital converter 60. The analog-to-digital converter 60 then converts the voltage sensing signals Vs stored in each storage module 30 into a digital voltage signal Vd, which is output to the control module 40 for storage. The display device can adjust its display based on the stored digital voltage signal Vd. For example, related control devices of the display device can access the control module 40 via a serial interface to adjust the display brightness according to the stored digital voltage signal Vd. For instance, if the ambient light is low based on this signal level, the display brightness can be reduced.

[0039] Figure 3 This is a schematic diagram of an ambient light detection circuit according to an embodiment of the present disclosure, such as... Figure 3 As shown, in an exemplary embodiment, the detection circuit may include four sensing modules: a first sensing module 11 to a fourth sensing module 14. The first sensing module 11 can sense red light, the second sensing module 12 can sense green light, the third sensing module 13 can sense blue light, and the fourth sensing module 14 can sense white light. The control module 40 or other control devices of the display device can calculate the color temperature and intensity of the current ambient light based on the sensing signals from the first sensing module 11, the second sensing module 12, and the third sensing module 13, and can further verify the calculated ambient light intensity based on the sensing signal from the fourth sensing module 14. It should be understood that the first sensing modules 11 to the fourth sensing modules 14 may have the same circuit structure, for example, they may be composed of the same photoelectric sensor, and the first sensing module 11, the second sensing module 12, and the third sensing module 13 may be formed by setting a color filter layer on the photoelectric sensor.

[0040] Accordingly, such as Figure 3As shown, the multiple current conversion modules 20 may include a first current conversion module 21 to a fourth current conversion module 24, and the multiple storage modules 30 may include a first storage module 31 to a fourth storage module 34. The first current conversion module 21 is connected to the first sensing module 11 and is used to convert the current sensing signal Idr output by the first sensing module 11 into a corresponding voltage sensing signal Vsr. The first storage module 31 is connected between the first current conversion module 21 and the gating module 50 to store the voltage sensing signal Vsr output by the first current conversion module 21. The second current conversion module 22 is connected to the second sensing module 12 and is used to convert the current sensing signal Idg output by the second sensing module 12 into a corresponding voltage sensing signal Vsg. The second storage module 32 is connected between the second current conversion module 22 and the gating module 50 to store the voltage sensing signal Vsg output by the second current conversion module 22. The third current conversion module 23 is connected to the third sensing module 13 and is used to convert the current sensing signal Idb output by the third sensing module 13 into the corresponding voltage sensing signal Vsb. The third storage module 33 is connected between the third current conversion module 23 and the gating module 50 to store the voltage sensing signal Vsb output by the third current conversion module 23. The fourth current conversion module 24 is connected to the fourth sensing module 14 and is used to convert the current sensing signal Idw output by the fourth sensing module 14 into the corresponding voltage sensing signal Vsw. The fourth storage module 34 is connected between the fourth current conversion module 24 and the gating module 50 to store the voltage sensing signal Vsw output by the fourth current conversion module 24.

[0041] The following section, with reference to the accompanying diagram, further describes each functional module in the detection circuit.

[0042] like Figure 3 As shown, in an exemplary embodiment, the sensing module 10 may include a photoelectric sensor. The cathode of the photoelectric sensor may be connected to the Vsensor voltage terminal, and the anode of the photoelectric sensor may be connected to the input terminal of the current conversion module 20. The sensing module 10 may output a current sensing signal Id of a corresponding magnitude based on the optical signal. The current sensing signal Id is output to the current conversion module 20 and converted into a voltage sensing signal Vs by the current conversion module 20.

[0043] like Figure 3As shown, in an exemplary embodiment, the current conversion module 20 may include a signal amplification unit, a gain adjustment unit, and a feedback unit. One input terminal of the signal amplification unit is connected to a reference voltage terminal, and the other input terminal of the signal amplification unit is connected to the output terminal of the corresponding sensing module 10. One end of the gain adjustment unit is connected to the output terminal of the corresponding sensing module 10, and the other end of the gain adjustment unit is connected to the output terminal of the signal amplification unit. The gain adjustment unit is used to determine the voltage sensing signal Vs according to the selected gain coefficient. The feedback unit is connected in parallel across the two ends of the gain adjustment unit. The feedback unit is used to prevent the signal amplification unit from self-oscillating and to increase the stability of the signal amplification unit.

[0044] The signal amplification unit may include an operational amplifier (OP), with one input terminal of the OP connected to a reference voltage terminal and the other input terminal connected to the output terminal of the corresponding sensing module 10. The feedback unit may include a feedback capacitor Cf connected in parallel across the gain branch. The gain adjustment unit may include multiple parallel gain branches, each of which may include a gain resistor Rg and a gain control switch Tg. The gain resistor Rg and the gain control switch Tg are connected in series, and the gain control switch Tg can be used to activate the corresponding gain branch in response to the gain control signal Gain to adjust the gain coefficient of the gain adjustment unit. The gain coefficient can be understood as the amplification factor of the current sensing signal Id. Obviously, the magnitude of the gain resistor Rg determines the gain coefficient of the gain branch. By reasonably configuring the relationship between the magnitudes of the gain resistors Rg, the gain levels of the gain adjustment unit can be changed step by step according to a certain ratio. For example, as shown... Figure 3 As shown, the gain adjustment unit can include four gain branches. For example, the gain resistors Rg of different gain branches are in a 10-fold relationship, i.e., Rg1 = 10 * Rg2 = 10 * 10 * Rg3 = 10 * 10 * 10 * Rg4, thus enabling the gain adjustment unit to have 10X levels. It should be understood that the minimum gain resistor Rg can be determined based on the maximum induced current generated on the sensing module by the maximum ambient light brightness and the output voltage range of the operational amplifier (OP) in the current conversion module 20. Furthermore, the gain control signal Gain is output by the control module 40. When the gain control switch is a transistor switch, the control module 40 can output the gain control signal Gain to the level conversion module 70, which converts the gain control signal Gain into high and low level signals and outputs them to each gain control switch Tg to drive and control the gain control switches Tg.

[0045] For example, the gain adjustment unit may include four gain branches, each including a gain resistor Rg and a gain control switch Tg connected in series. The gain resistor Rg is different for different gain branches. When the gain control switch Tg of a certain gain branch is turned on, that gain branch is turned on, causing the gain adjustment unit to have a corresponding gain coefficient. That is, the gain adjustment circuit outputs a voltage sensing signal Vs of a corresponding magnitude based on the gain coefficient. For example, the four gain branches may be a first gain branch, a second gain branch, a third gain branch, and a fourth gain branch. The first gain branch includes a first gain resistor Rg1 and a first gain control switch Tgg1, the second gain branch includes a second gain resistor Rg2 and a second gain control switch Tgg2, the third gain branch includes a third gain resistor Rg3 and a third gain control switch Tgg3, and the fourth gain branch includes a fourth gain resistor Rg4 and a fourth gain control switch Tgg4. The control module 40 can sequentially output gain control signals Gain with different conduction levels in a time-division manner to activate each gain branch. The current conversion module 20 outputs a voltage sensing signal Vs of corresponding magnitude according to the gain coefficient of the activated gain branch. Obviously, with the gain adjustment unit having the four gain paths mentioned above, the current conversion module 20 can output four different voltage sensing signals Vs with different gain magnitudes. It is understandable that the conduction level is determined according to the type of the gain control switch Tg. For example, if the gain control switch Tg is an N-type transistor switch, then the conduction level of the gain control signal Gain is high.

[0046] like Figure 3 As shown, in an exemplary embodiment, each current conversion module 20 may have the same structure. For example, each current conversion module 20 may include four gain branches, and the structures of the four gain branches are identical. Specifically, each current conversion module 20 may include a first gain branch, a second gain branch, a third gain branch, and a fourth gain branch. Furthermore, the first gain branch in each current conversion module 20 includes a first gain resistor Rg1 and a first gain control switch Tgg1; the second gain branch in each current conversion module 20 includes a second gain resistor Rg2 and a second gain control switch Tgg2; the third gain branch in each current conversion module 20 includes a third gain resistor Rg3 and a third gain control switch Tgg3; and the fourth gain branch in each current conversion module 20 includes a fourth gain resistor Rg4 and a fourth gain control switch Tgg4. Based on this, the control module 40 can synchronously output a gain control signal Gain to the same gain branch in each current conversion module 20, so that each current conversion module 20 outputs a voltage sensing signal Vs at the same gain level at the same time. For example, control module 40 can synchronously send... Figure 3The four first gain control switches Tgg1 output the first gain control signal Gain1, which in turn controls each current conversion module 20 to synchronously output the voltage sensing signal Vs of the first gain level.

[0047] As mentioned above, the sensing module 10 can be a photoelectric sensor, to... Figure 3 For example, the cathode of the photoelectric sensor can be connected to the Vsensor voltage terminal, the anode of the photoelectric sensor can be connected to the inverting input terminal of the operational amplifier (OP), and the non-inverting input terminal of the OP can be connected to the reference voltage terminal Vref. Based on the virtual short characteristic of the OP, the anode voltage of the sensing module 10 is Vref. The Vsensor voltage can be set according to the electrical characteristics of the photoelectric sensor, and the reverse bias level of each photoelectric sensor can be further determined based on the Vsensor voltage.

[0048] For example, such as Figure 3 As shown, the first current conversion module 21 may include a first operational amplifier OP1, the second current conversion module 22 may include a second operational amplifier OP2, the third current conversion module 23 may include a third operational amplifier OP3, and the fourth current conversion module 24 may include a fourth operational amplifier OP4. When the first gain control signal Gain1 is on, the first gain control switch Tgg1 is on, and the first gain resistor Rg1 is connected to the sensing module 10. The output voltage of the first operational amplifier OP1 is the voltage drop across the current sensing signal Id on the first gain resistor Rg1, which is Vout = Vref - Id * Rg1. When the second gain control signal Gain2 is on, the second gain control switch Tgg2 is on, and the second gain resistor Rg2 is connected to the sensing module 10. The output voltage of the first operational amplifier OP1 is the voltage drop across the sensing current on the second gain resistor Rg2, which is Vout = Vref - Id * Rg2. Similarly, when the third gain control signal is on, the third gain resistor Rg3 is connected to the sensing module 10, and the output voltage is Vout = Vref - Id * Rg3. When the fourth gain control signal Gain4 is on, the fourth gain resistor Rg4 is connected to the sensing module 10, and the output voltage is Vout = Vref - Id * Rg4. It can be seen that when the voltage range of the back-end analog-to-digital conversion module 60 is fixed, the larger the gain resistor Rg is, the smaller the current that the gain branch can collect. For example, when Rg1 = 10*Rg2 = 10*10*Rg3 = 10*10*10*Rg4, the gain coefficient of the fourth gain branch is the largest, and the gain coefficient of the first gain branch is the smallest. Correspondingly, the induced voltage output by the fourth gain branch is the largest, and the induced voltage output by the first gain branch is the smallest.

[0049] In an exemplary embodiment, in any gain branch, the ratio of the on-resistance of the gain control switch Tg to the gain resistor Rg connected thereto is less than or equal to 1%, for example, it can be 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, etc. For example, such as... Figure 3 As shown, for the first gain branch, the ratio of the on-resistance of the first gain control switch Tgg1 to the first gain resistor Rg1 is less than or equal to 1%, the ratio of the on-resistance of the second gain control switch Tgg2 to the second gain resistor Rg2 is less than or equal to 1%, the ratio of the on-resistance of the third gain control switch Tgg3 to the third gain resistor Rg3 is less than or equal to 1%, and the ratio of the on-resistance of the fourth gain control switch Tgg4 to the fourth gain resistor Rg4 is less than or equal to 1%. By setting the ratio of the on-resistance of the gain control switch Tg to the gain resistor Rg connected to it in the above relationship, this disclosure can sufficiently reduce the voltage drop of the gain control switch Tg when it is turned on. This can significantly reduce the voltage drop loss of the current sensing signal Id at the gain control switch Tg, allowing the voltage sensing signal Vs output by the current conversion module 20 to more accurately reflect the current ambient light information, which may include, for example, light intensity and color temperature. In an exemplary embodiment, the gain control switch Tg can be a transistor switch, and the on-resistance of the transistor switch can be reduced by increasing the aspect ratio of the channel region of the transistor switch.

[0050] Furthermore, in an exemplary embodiment, in any gain branch, the ratio of the leakage current of the gain control switch Tg to the induced current of the connected sensing module 10 is less than or equal to 1%. For example, it can be 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, etc. For instance, such as... Figure 3As shown, in the first current conversion module 21, the ratio of the leakage current of the first gain control switch Tgg1 to the first induced current of the first sensing module 11 is less than or equal to 1%; the ratio of the leakage current of the second gain control switch Tgg2 to the first induced current of the first sensing module 11 is less than or equal to 1%; the ratio of the leakage current of the third gain control switch Tgg3 to the first induced current of the first sensing module 11 is less than or equal to 1%; and the ratio of the leakage current of the fourth gain control switch Tgg4 to the first induced current of the first sensing module 11 is less than or equal to 1%. It is understood that the gain control switches of each gain path in the other current conversion modules 20 have the same leakage current characteristics, which will not be detailed here. The advantage of this arrangement is that, at any given time, only one gain control switch Tg is turned on in a current conversion module 20. By reducing the leakage current of the gain control switch Tg, the gain branch where the unconverted gain control switch Tg is located will not cause leakage current to the induced current. As a result, the induced current generated by the sensing module 10 will not be wasted or will be wasted by other unconverted gain branches, thereby enabling the voltage sensing signal Vs output by the current conversion module 20 to more accurately reflect the current ambient light information.

[0051] As described above, the same gain branch in different current conversion modules 20 of this disclosure can reuse the same gain control signal Gain, so that different current conversion modules 20 can output voltage sensing signals Vs at the same gain level at the same time. The same gain branch is a gain branch with the same gain coefficient. For example, Figure 4 This is a timing diagram of the control signal for one sampling period according to an embodiment of the present disclosure, where T represents one sampling period, as shown below. Figure 4 As shown, the control module 40 completes the signal acquisition of four gain coefficients within one sampling period. That is, one sampling period includes four sub-sampling periods. One sub-sampling period is the signal acquisition time of one gain coefficient. In other words, one sub-sampling period is the time from when the gain control switch Tg turns on and outputs the current sensing signal Id to when the control module 40 obtains the digital voltage signal Vd of that gain level. It is also the interval between when one gain control switch turns on and when the next gain control switch turns on.

[0052] It should be understood. Figure 4While the duration of each sub-sampling period is the same, in practical applications, the sub-sampling periods corresponding to different gain coefficients can be different. For example, in some embodiments, the duration of the sub-sampling period can be set according to the magnitude of the gain resistor in the gain branch. For instance, the conduction time of the gain control signal corresponding to the gain branch with a larger gain resistor can be set to a larger duration, and the conduction level time of the gain control signal corresponding to the gain branch with a smaller gain resistor can be set to a smaller duration. The advantage of this setting is that when the gain resistor is large, by setting the conduction level time of the gain control signal of that gain branch to a longer duration, the induced voltage signal of that gain branch can be fully released, thereby preventing the gain resistor from self-oscillating with the operational amplifier. Figure 4 As shown, within one sampling period, the control module 40 can sequentially output the fourth gain control signal Gain4, the third gain control signal Gain3, the second gain control signal Gain2, and the first gain control signal Gain1 in a time-division manner. The conduction level of the fourth gain control signal Gain4 controls the fourth gain branch in the four current conversion modules 20 to be simultaneously turned on, so that each current conversion module 20 synchronously outputs the voltage sensing signal Vs of the fourth gain level. Similarly, the conduction level of the third gain control signal Gain3 can control the third gain branch in the four current conversion modules 20 to be simultaneously turned on, so that each current conversion module 20 synchronously outputs the voltage sensing signal Vs of the fourth gain level. Block 20 synchronously outputs the voltage sensing signal Vs of the third gain level. The conduction level of the second gain control signal Gain2 can control the second gain branch in the four current conversion modules 20 to conduct simultaneously, so that each current conversion module 20 synchronously outputs the voltage sensing signal Vs of the second gain level. The conduction level of the first gain control signal Gain1 can control the first gain branch in the four current conversion modules 20 to conduct simultaneously, so that each current conversion module 20 synchronously outputs the voltage sensing signal Vs of the first gain level. Thus, within one sampling period, multiple current sensing modules 10 are controlled to complete the signal acquisition of the four gain levels respectively.

[0053] Furthermore, as mentioned above, the storage module 30 corresponds one-to-one with the current conversion module 20 and the sensing module 10; that is, one sensing module 10 is connected to one current conversion module 20, and one current conversion module is connected to one storage module 30. The control module 40 can synchronously output a sampling control signal SMPL of the conduction level to each storage module 30 to synchronously turn on each storage module 30, thereby enabling each storage module 30 to store the voltage sensing signal Vs at the same time.

[0054] The control module 40 can output a sampling control signal SMPL with a conduction level within the conduction time of the gain control signal Gain. This allows the detection circuit to control its respective storage modules 30 to store the voltage sensing signal Vs corresponding to the optical signal at the same moment when acquiring optical signals according to a certain gain. For example, after outputting the fourth gain control signal Gain4 with a conduction level, the control module 40 can output the sampling control signal SMPL with a conduction level after a preset time interval to connect each storage module 30 to the corresponding current conversion module 20. This controls each storage module 30 to synchronously store the voltage sensing signal Vs amplified by each sensing module 10 using the same gain level. The conduction level of the sampling control signal SMPL output by the control module 40 is later than the conduction level of the gain control signal Gain. This allows the voltage sensing signal Vs of the previous sub-sampling cycle stored in the feedback capacitor Cf to be fully released, thereby ensuring that the voltage sensing signal Vs stored in the feedback capacitor Cf more accurately reflects the optical signal at the current sampling moment. Understandably, the conduction level of the sampling control signal SMPL varies depending on the type of the sampling switch Ts. For example, when the sampling switch Ts is an N-type transistor switch, the conduction level of the sampling control signal SMPL is high.

[0055] like Figure 3 As shown, in an exemplary embodiment, the storage module 30 may include a storage capacitor, a filtering unit 35, and a sampling switch Ts. The filtering unit 35 is connected between the corresponding operational amplifier OP and the gating module 50. The sampling switch Ts is connected in series between the filtering unit 35 and the corresponding operational amplifier OP, and the control terminal of the sampling switch Ts receives a sampling control signal SMPL. In response to the sampling control signal SMPL, the sampling switch Ts transmits the voltage sensing signal Vs output by the current conversion module 20 connected to it to the filtering unit 35 for storage.

[0056] As described above, the current conversion module 20 specifically outputs a voltage sensing signal Vs through an operational amplifier (OP). A sampling switch Ts is connected in series between the filter unit 35 and the corresponding OP, so that the sampling switch Ts can control the filter unit 35 to connect to or disconnect from the corresponding OP in response to the sampling control signal SMPL. When the sampling control signal SMPL is on, the sampling switch Ts is on, and the filter unit 35 is connected to the corresponding OP to obtain and store the voltage sensing signal Vs output by the OP. When the sampling control signal SMPL is off, the sampling switch Ts is off, and the filter unit 35 is disconnected from the corresponding OP.

[0057] The filtering unit 35 may include a filtering resistor R and a storage capacitor C. Here, the storage capacitor and the filtering resistor form a low-pass filter. One end of the filtering resistor R is connected to the first terminal of the filtering unit 35, and the other end of the filtering resistor R is connected to the second terminal of the filtering unit 35. One end of the storage (filtering) capacitor C is connected to the second terminal of the filtering unit 35, and the other end of the storage capacitor C is grounded. The filtering resistor R and the storage capacitor C can form a low-pass filter. As described above, when the sampling switch Ts is turned on, the voltage sensing signal Vs output by the operational amplifier OP is transmitted to the storage capacitor C for storage. The control module 40 can further control the gating module 50 to turn on, so that the voltage sensing signal Vs stored in the storage capacitor C is output to the analog-to-digital conversion module 60 to be converted into a digital voltage signal Vd.

[0058] like Figure 4 As shown, in an exemplary embodiment, the on-level of the sampling control signal SMPL and the on-level of the gain control signal Gain can at least partially overlap, so that each storage cell can store a voltage sensing signal Vs at the same gain level. For example, the control module 40 can output the sampling control signal SMPL with the on-level during the on-level duration of the gain control signal Gain.

[0059] In addition, such as Figure 4 As shown, during the sampling process of an optical signal at any gain, the start time of the conduction level of the sampling control signal SMPL is later than the start time of the conduction level of the gain control signal Gain. Specifically, after outputting the conduction level gain control signal Gain, the control module 40 can output the conduction level sampling control signal SMPL after a preset time interval to connect each storage module 30 with the corresponding current conversion module 20, thereby controlling each storage module 30 to synchronously store the voltage sensing signal Vs after signal amplification by each sensing module 10 using the same gain level. The conduction level of the sampling control signal SMPL output by the control module 40 of this disclosure is later than the conduction level of the gain control signal Gain. This delay time needs to ensure that the voltage sensing signal Vs stored in the feedback capacitor Cf at the previous moment is fully released to eliminate the influence of residual signals on the voltage sensing signal Vs at the current sampling moment.

[0060] In an exemplary embodiment, the gating module 50 may include multiple gating switches MUX, such as transistor switches. The number of gating switches MUX can correspond one-to-one with the number of storage modules 30, i.e., one gating switch MUX is connected to one storage module 30. When a gating switch MUX is turned on, the voltage sensing signal Vs stored in the connected storage module 30 can be transmitted to the analog-to-digital converter module 60. For example, such as Figure 3As shown, the storage module 30 may include a first storage module 31 to a fourth storage module 34, and the gating module 50 may be a 4:1 MUX switch, specifically including a first gating switch MUX1 to a fourth gating switch MUX4. The first gating switch MUX1 is connected between the first storage module 31 and the analog-to-digital converter module 60, the second gating switch MUX2 is connected between the second storage module 32 and the analog-to-digital converter module 60, the third gating switch MUX3 is connected between the third storage module 33 and the analog-to-digital converter module 60, and the fourth gating switch MUX4 is connected between the fourth storage module 34 and the analog-to-digital converter module 60. When the first gating switch MUX1 is turned on, the voltage sensing signal Vs stored in the first storage module 31 can be transmitted to the analog-to-digital converter module 60. When the second gating switch MUX2 is turned on, the voltage sensing signal Vs stored in the second storage module 32 can be transmitted to the analog-to-digital converter module 60. And so on. The control module 40 outputs gating control signals MX in sequence so that the analog-to-digital converter module 60 can obtain the voltage sensing signals Vs of each storage module 30 respectively.

[0061] In an exemplary embodiment, the ratio of the time constant τ formed by the turn-off resistance and storage capacitor of any selector switch MUX to one sampling period can be greater than or equal to 10 / n, where n is the number of gain branches included in the current conversion module, and n is a positive integer greater than or equal to 1. For example, it can be 10, 11, 12, 13, 14, 15, etc. Here, one sampling period includes... Figure 4 The four sub-sampling periods. In other words, the ratio of the time constant τ formed by the storage capacitor to one sub-sampling period is greater than or equal to 10. Since the size of the storage capacitor is already determined, increasing the turn-off resistance of the gating switch MUX and the time constant τ formed by the storage capacitor requires increasing the turn-off resistance of the gating switch MUX, thereby reducing the leakage current of the gating switch MUX. This disclosure can sufficiently increase the turn-off resistance of the gating switch MUX through the above method, thus preventing the induced voltage stored in the filter unit 35 from leaking through the unconducted gating switch MUX, thereby making the voltage induced signal Vs output by the filter module to the analog-to-digital conversion module 60 more accurately reflect the current optical signal. In an exemplary embodiment, the gating switch MUX can be implemented by a transistor, and the turn-off resistance of the gating switch MUX can be increased by increasing the width-to-length ratio of the transistor's channel region.

[0062] The analog-to-digital converter module 60 described in this disclosure can be an integrated device, such as an analog-to-digital converter chip. The sampling accuracy of the analog-to-digital converter module 60 needs to match the usage requirements of the display device. The specific process and principle of the analog-to-digital converter module 60 will not be detailed here. The level conversion module 70 can convert the control signals generated by the control module 40 into high and low level signals (VGH / VGL) to drive the gain control switch Tg, the sampling switch Ts, and the gating switch MUX.

[0063] In an exemplary embodiment, the control module 40 can also be used to filter the digital voltage signal Vd output by the analog-to-digital conversion module 60, and store the qualified digital voltage signal Vd as the effective voltage signal of the current sampling period. For example, the control module 40 can compare the digital voltage signal Vd at each gain level with two terminal voltage values ​​within a preset voltage range. When the digital voltage signal Vd is within the preset voltage range, the control module 40 saves the digital voltage signal Vd as the effective voltage signal of the current sampling period, and then samples the next sub-sampling period, using the same method to filter the digital voltage signal Vd. Furthermore, it should be understood that when more than one gain level of digital voltage signal Vd is within the preset voltage range in a sampling period, the control module 40 can save the digital voltage signal Vd with the largest value as the effective voltage signal of the current sampling period. It should be understood that the above methods for determining the effective voltage signal are merely illustrative and should not be construed as limiting the present disclosure. In other embodiments of the present disclosure, the effective voltage signal for each sampling period can be determined in other ways.

[0064] Figure 5 This is a flowchart of an ambient light detection method according to an embodiment of the present disclosure. This detection method can be applied to the ambient light detection circuit described in any embodiment of the present disclosure. The detection method can be executed by a control module in a display device, such as a microcontroller or a programmable logic device. Figure 5 As shown, the method may include the following steps:

[0065] S110: Control the synchronous conduction of each current conversion module within one sampling period;

[0066] S120. During the conduction time of the current conversion module, a sampling control signal is synchronously output to each storage module to control each storage module to store the voltage sensing signal output by the current conversion module connected to it.

[0067] S130. Obtain the voltage sensing signals stored in each storage module and preprocess each voltage sensing signal.

[0068] In this disclosed control detection method, within a sampling period, the control module can control the current conversion modules connected to each sensing module to conduct synchronously, so that each current sensing module can output voltage sensing signals based on the same moment. The control module further synchronously outputs sampling control signals SMPL to each storage module, which can control each storage module to store the voltage sensing signals output by the current conversion modules connected to it. This ensures that the voltage sensing signals stored by each storage module are voltage sensing signals at the same moment, thereby solving the problem of asynchronous optical signals of different sensing modules in related technologies.

[0069] The steps described above in this example implementation will now be explained in more detail.

[0070] In step S110, the control module controls each current conversion module to conduct synchronously within one sampling period.

[0071] As described in the above embodiments, the current conversion module may include a signal amplification unit, a gain adjustment unit, and a feedback unit. The signal amplification unit may include an operational amplifier (op-amp), with one input terminal connected to a reference voltage terminal and the other input terminal connected to the output terminal of the corresponding sensing module. The gain adjustment unit may include multiple parallel gain branches, each gain branch may include a gain resistor and a gain control switch, with the gain resistor and gain control switch connected in series. The gain control switch can be used to turn on the corresponding gain branch in response to the gain control signal Gain to adjust the gain coefficient of the gain adjustment unit. The feedback unit may include a feedback capacitor connected in parallel across the two ends of the gain branch. In one sampling period, the control module may, as follows: Figure 4 The control module outputs a gain control signal Gain, indicating the conduction level, to the gain control switch according to a preset timing sequence to time-division multiplex the gain branches. Because each current conversion module has the same circuit structure, the control module can synchronously output the gain control signal Gain to each current conversion module to synchronously activate the gain branches with the same gain coefficient in each current conversion module. For example, the control module can synchronously output the first gain control signal Gain1 to the first gain branches in the first current conversion module, the second current conversion module, the third current conversion module, and the fourth current conversion module, so that the four first gain branches are synchronously activated. Then, the control module simultaneously outputs the second gain control signal Gain2 to the first to fourth current conversion modules to synchronously activate the four second gain branches, and so on. The control module can control the synchronous activation of each current conversion module, enabling each current conversion module to synchronously output a voltage sensing signal at the same gain level.

[0072] In step S120, during the conduction time of the current conversion module, the control module synchronously outputs a sampling control signal SMPL of the conduction level to each storage module to control each storage module to store the voltage sensing signal output by the current conversion module connected to it.

[0073] For example, the control module can be as follows Figure 4 The time-division multiplexing output sampling control signal SMPL, as shown, controls the control module to output a sampling control signal SMPL with an on-level to each sampling switch within the on-level duration of each gain control signal Gain, thereby controlling the sampling switches to conduct synchronously. This allows each storage module to synchronously store voltage sensing signals at the same gain level. In other words, the control module can synchronously output the sampling control signal SMPL with an on-level to each storage module after a preset duration of outputting the gain control signal Gain, controlling each storage module to store the voltage sensing signal output by the current conversion module connected to it. The on-level of the sampling control signal SMPL and the on-level of the gain control signal Gain at least partially overlap.

[0074] As described above, the storage module may include a filtering unit and a sampling switch. The filtering unit is connected between the corresponding operational amplifier and the gating module, and the sampling switch is connected in series between the filtering unit and the corresponding operational amplifier. The control terminal of the sampling switch receives a sampling control signal SMPL. The sampling switch, in response to the sampling control signal SMPL, transmits the voltage sensing signal output from the conversion unit connected to it to the filtering unit for storage. The filtering unit may consist of a filtering resistor and a storage capacitor. When the sampling switch receives the on-level sampling control signal SMPL, the sampling switch conducts, connecting the filtering unit to the output terminal of the corresponding operational amplifier, thereby storing the voltage sensing signal at the current sampling moment. Because each sampling switch synchronously receives the on-level sampling control signal SMPL, each filtering unit can synchronously store the voltage sensing signal at the current moment.

[0075] In step S130, the control module acquires the voltage sensing signals stored in each storage module and preprocesses each voltage sensing signal.

[0076] As mentioned above, the detection circuit may further include a gating module, an analog-to-digital converter (ADC) module, and a level conversion module. The gating module is connected in series between the storage module and the control module. The gating module can be used to activate the connection path between the corresponding storage module and the control module in response to the gating control signal MX output by the control module. The ADC module is connected in series between the gating module and the control module. The ADC module can be used to convert the acquired voltage sensing signal into a digital voltage signal for output. The level conversion module is connected to the control module. The level conversion module can be used to convert the various control signals of the control module (including the sampling control signal SMPL, the gain control signal Gain, and the gating control signal MX) into corresponding level signals and output them to the corresponding switching modules.

[0077] Based on this, step S130 may specifically include the following steps:

[0078] The gating control signal MX is output to the gating module to transmit the voltage sensing signal stored in the corresponding storage module to the analog-to-digital converter module. The analog-to-digital converter module converts the acquired voltage sensing signal into a digital voltage signal.

[0079] Filtering digital voltage signals;

[0080] If the digital voltage signal is a valid voltage signal, then the valid voltage signal is saved.

[0081] The gating module can include multiple gating switches (MUX). The number of gating switches (MUX) corresponds one-to-one with the number of storage modules. That is, one gating switch (MUX) controls the connection between one storage module and the analog-to-digital converter module. The control module can sequentially output a gating control signal (MX) with a conduction level to each gating switch (MUX), controlling each storage module to sequentially output its stored voltage sensing signal to the analog-to-digital converter module to convert it into a digital voltage signal.

[0082] It is worth noting that the control module of this disclosure can filter the acquired digital voltage signals, that is, filter the digital voltage signals of each gain level. When the digital voltage signal is within the set voltage range, the control module determines that the digital voltage signal is a valid voltage signal and saves it. When the digital voltage signal is outside the set voltage range, the control module discards the digital voltage signal. In some embodiments, when the digital voltage signals corresponding to the voltage sensing signals of multiple gain levels are within the set voltage range, the control module can store the digital voltage signal with the largest value as the valid voltage signal of the current sampling period. The external circuit can directly read the data in the specified memory through a serial interface, such as an I / O interface. 2 Other serial ports such as C or SPI.

[0083] This disclosure also provides a display device that may include the ambient light detection circuit described in any of the above embodiments. The display device may be, for example, a mobile phone, a tablet, etc. The display device can adjust its display based on the ambient light detected by the ambient light detection circuit; for example, it can automatically adjust the display brightness according to the ambient light.

[0084] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the generality of this disclosure and include, but are not disclosed herein, common knowledge or customary techniques in the art. The specification and embodiments are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the claims.

Claims

1. An ambient light detection circuit, characterized in that, The detection circuit is used for ambient light detection of the display panel, and includes: The system includes multiple sensing modules for collecting ambient light and outputting current sensing signals based on the ambient light. These modules include a first sensing module, a second sensing module, a third sensing module, and a fourth sensing module. The first sensing module senses ambient red light, the second sensing module senses ambient green light, the third sensing module senses ambient blue light, and the fourth sensing module senses ambient white light. All four sensing modules (first, second, third, and fourth) are constructed from the same photoelectric sensor. The first, second, and third sensing modules are formed by depositing a color filter layer on the photoelectric sensor. Multiple current conversion modules are configured corresponding to multiple sensing modules. The current conversion modules are used to convert the current sensing signals output by the sensing modules connected to them into voltage sensing signals. Multiple storage modules are configured corresponding to multiple current conversion modules. The storage modules are used to store the voltage sensing signals output by the current conversion modules connected to them in response to sampling control signals. A control module is connected to each of the storage modules, and the control module is used to synchronously output the sampling control signal to each of the storage modules. A gating module is connected in series between the storage module and the control module. The gating module is used to respond to the gating control signal output by the control module to connect the corresponding storage module and the control module. An analog-to-digital converter module is connected in series between the gating module and the control module. The analog-to-digital converter module is used to convert the acquired voltage sensing signal into a digital voltage signal for output. The current conversion module includes: The signal amplification unit has one input terminal connected to the reference voltage terminal and the other input terminal connected to the output terminal of the corresponding sensing module. The gain adjustment unit is connected at one end to the output terminal of the corresponding sensing module and at the other end to the output terminal of the signal amplification unit. The gain adjustment unit is used to determine the voltage sensing signal according to the selected gain coefficient. A feedback unit is connected in parallel across the two ends of the gain adjustment unit. The feedback unit is used to prevent the signal amplification unit from self-oscillating. The gain adjustment unit includes multiple parallel gain branches, and the gain branches include: Gain resistor; A gain control switch, connected in series with the gain resistor, is used to turn on the corresponding gain branch in response to the gain control signal output by the control module to adjust the gain coefficient of the gain adjustment unit. The feedback unit includes: A feedback capacitor is connected in parallel across the two ends of the gain branch; The signal amplification unit includes: The operational amplifier has one input terminal connected to the reference voltage terminal and the other input terminal connected to the output terminal of the corresponding sensing module. During the process of acquiring optical signals according to any gain coefficient, the on-level of the sampling control signal and the on-level of the gain control signal at least partially overlap, and the start time of the on-level of the sampling control signal is later than the start time of the on-level of the gain control signal. The storage module includes: A filtering unit is connected between the corresponding operational amplifier and the gating module; A sampling switch is connected in series between the filtering unit and the corresponding operational amplifier, and the control terminal of the sampling switch receives the sampling control signal; The sampling switch, in response to the sampling control signal, transmits the voltage sensing signal output by the current conversion module connected to it to the filtering unit for storage. The control module is used to filter the digital voltage signals corresponding to each of the gain branches.

2. The detection circuit according to claim 1, characterized in that, The detection circuit further includes: A level conversion module is connected to the control module, and the level conversion module is used to convert the sampling control signal into a corresponding level signal for output.

3. The detection circuit according to claim 1, characterized in that, The ratio of the on-resistance of the gain control switch to the gain resistor connected to it is less than or equal to 1%.

4. The detection circuit according to claim 1, characterized in that, The ratio of the leakage current of the gain control switch to the induced current of the connected sensing module is less than or equal to 1%.

5. The detection circuit according to claim 1, characterized in that, Gain branches with the same gain coefficient in different current conversion modules reuse the same gain control signal; The conduction levels of the gain control signals corresponding to gain branches with different gain coefficients do not overlap.

6. The detection circuit according to claim 1, characterized in that, The gain adjustment unit includes a first gain branch, a second gain branch, a third gain branch, and a fourth gain branch. The resistance values ​​of the gain resistors in the first gain branch, the second gain branch, the third gain branch, and the fourth gain branch increase sequentially.

7. The detection circuit according to claim 1, characterized in that, The storage module includes: A filtering unit is connected between the corresponding operational amplifier and the gating module; A sampling switch is connected in series between the filtering unit and the corresponding operational amplifier, and the control terminal of the sampling switch receives the sampling control signal; Specifically, the sampling switch responds to the sampling control signal by transmitting the voltage sensing signal output by the current conversion module connected to it to the filtering unit for storage.

8. The detection circuit according to claim 7, characterized in that, The filtering unit includes: A filter resistor, one end of which is connected to the first terminal of the filter unit, and the other end of which is connected to the second terminal of the filter unit; The storage capacitor has one end connected to the second terminal of the filter unit and the other end grounded.

9. The detection circuit according to claim 8, characterized in that, The gating module includes: Multiple selection switches are configured to correspond one-to-one with the multiple storage modules, and the control terminal of each selection switch receives the selection control signal. Wherein, the ratio of the time constant formed by the turn-off resistor of the arbitrary selection switch and the storage capacitor to one sampling period is greater than or equal to 10 / n, where n is the number of gain branches included in the current conversion module, and n is a positive integer greater than or equal to 1.

10. The detection circuit according to claim 1, characterized in that, The control module is also used for: Obtain the digital voltage signal corresponding to the voltage sensing signal output by each gain branch; Digital voltage signals within a preset voltage range are selected as valid voltage signals.

11. An ambient light detection method, characterized in that, Applied to the ambient light detection circuit according to any one of claims 1-10, the method is executed by a control module, and the method includes: Control each current conversion module to conduct synchronously within a sampling period; During the conduction time of the current conversion module, a sampling control signal of the conduction level is synchronously output to each storage module to control each storage module to store the voltage sensing signal output by the current conversion module connected to it. The voltage sensing signals stored in each of the storage modules are acquired respectively, and each voltage sensing signal is preprocessed.

12. An ambient light detection method, characterized in that, Applied to the ambient light detection circuit of claim 1, the method is executed by a control module, and the method includes: Control each current conversion module to conduct synchronously within a sampling period; During the conduction time of the current conversion module, a sampling control signal is synchronously output to each storage module to control each storage module to store the voltage sensing signal output by the current conversion module connected to it. A gating control signal is output to the gating module to transmit the voltage sensing signal stored in the corresponding storage module to the analog-to-digital conversion module. The analog-to-digital conversion module is used to convert the acquired voltage sensing signal into a digital voltage signal. The digital voltage signal is filtered; If the digital voltage signal is a valid voltage signal, then the valid voltage signal is saved.

13. An ambient light detection method, characterized in that, Applied to the ambient light detection circuit of claim 1, the method is executed by a control module, and the method includes: Within a sampling period, gain control signals are output in a time-division manner according to a preset timing sequence to turn on each gain branch in a time-division manner; After a preset duration of the gain control signal that outputs the conduction level, a sampling control signal that outputs the conduction level is synchronously output to each storage module to control each storage module to store the voltage sensing signal output by the current conversion module connected to it. The conduction level of the sampling control signal and the conduction level of the gain control signal overlap at least partially. A gating control signal is output to the gating module to transmit the voltage sensing signal stored in the corresponding storage module to the analog-to-digital conversion module, and the analog-to-digital conversion module converts the acquired voltage sensing signal into a digital voltage signal. The digital voltage signal is filtered; If the digital voltage signal is a valid voltage signal, then the valid voltage signal is saved.

14. A display device, characterized in that, Includes the ambient light detection circuit according to any one of claims 1-10.

Images