Patent Application
20250210008
The present disclosure relates to the field of display technology, and in particular, to a detection circuit for ambient light, a detection method for ambient light, and a display apparatus.
With the development of the display technology, more and more functions can be achieved by a display device; for example, a display device may collect ambient light by itself, and may perform display color and temperature adjustment and display brightness adjustment according to the ambient light, or the like. In the related art, a sensing device for sensing ambient light has a problem of asynchronous signal sensing.
It should be noted that the information disclosed in the above background part is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute the related art known to those of ordinary skill in the art.
An objective of the present disclosure is to overcome the shortcomings of the related art, and provide a detection circuit for ambient light, a detection method for ambient light, and a display apparatus.
According to an aspect of the present disclosure, there is provided a detection circuit for ambient light, configured to perform ambient light detection on a display panel, where the detection circuit includes: a plurality of sensing modules, where a sensing module is configured to collect ambient light and output a current sensing signal based on the ambient light; a plurality of current conversion modules, provided correspondingly to the plurality of sensing modules, where a current conversion module is configured to convert a current sensing signal output by a sensing module connected to the current conversion module into a voltage sensing signal; a plurality of storage modules, provided correspondingly to the plurality of current conversion modules, where a storage module is configured to store a voltage sensing signal output by a current conversion module connected to the storage module in response to a sampling control signal; and a control module, connected to the storage module respectively, where the control module is configured to output the sampling control signal synchronously to each storage module.
In some embodiments of the present disclosure, the detection circuit further includes: a gating module, connected in series between the storage modules and the control module, where the gating module is configured to turn on a communication path between a corresponding storage module and the control module in response to a gating control signal output by the control module; an analog-to-digital conversion module, connected in series between the gating module and the control module, where the analog-to-digital conversion module is configured to convert an obtained voltage sensing signal into a digital voltage signal for output; and a level-shift module, connected to the control module, where the level-shift module is configured to shift the sampling control signal into a corresponding level signal for output.
In some embodiments of the present disclosure, the current conversion module includes: a signal amplification unit, where an input end of the signal amplification unit is connected to a reference voltage end, and another input end of the signal amplification unit is connected to an output end of a corresponding sensing module; a gain adjustment unit, where an end of the gain adjustment unit is connected to the output end of the corresponding sensing module, another end of the gain adjustment unit is connected to an output end of the signal amplification unit, and the gain adjustment unit is configured to determine the voltage sensing signal according to a selected gain coefficient; and a feedback unit, connected in parallel to two ends of the gain adjustment unit, where the feedback unit is configured to prevent the signal amplification unit from being self-excited.
In some embodiments of the present disclosure, the gain adjustment unit includes a plurality of gain branches connected in parallel, and a gain branch includes: a gain resistor; a gain control switch, connected in series with the gain resistor, where the gain control switch is configured to turn on a corresponding gain branch in response to a gain control signal output by the control module, to adjust a gain coefficient of the gain adjustment unit. The feedback unit includes a feedback capacitor connected in parallel between two ends of the gain branch. The signal amplification unit includes an operational amplifier, where an input end of the operational amplifier is connected to the reference voltage end, and another input end of the operational amplifier is connected to an output end of a corresponding sensing module.
In some embodiments of the present disclosure, a ratio of an on-resistance of the gain control switch to a gain resistance connected to the gain control switch is less than or equal to 1%.
In some embodiments of the present disclosure, a ratio of a leakage current of the gain control switch to a sensing current of a sensing module connected to the gain control switch is less than or equal to 1%.
In some embodiments of the present disclosure, gain branches with a same gain coefficient in different current conversion modules multiplex with a same gain control signal; and on-levels of gain control signals corresponding to gain branches with different gain coefficients do not overlap with each other.
In some embodiments of the present disclosure, in a process of performing light signal collection according to any gain coefficient, an on-level of the sampling control signal at least partially overlaps with an on-level of the gain control signal, and an on-level start time of the sampling control signal is later than an on-level start time of the gain control signal.
In some embodiments of the present disclosure, the gain adjustment unit includes a first gain branch, a second gain branch, a third gain branch and a fourth gain branch; and, a resistance value of a gain resistor in the first gain branch, a resistance value of a gain resistor in the second gain branch, a resistance value of a gain resistor in the third gain branch, and a resistance value of a gain resistor in the fourth gain branch are increased sequentially.
In some embodiments of the present disclosure, the storage module includes: a filtering unit, connected between a corresponding operational amplifier and the gating module; and a sampling switch, connected in series between the filtering unit and the corresponding operational amplifier, where a control end of the sampling switch receives the sampling control signal; and where, in response to the sampling control signal, the sampling switch transmits a voltage sensing signal output by a current conversion module connected to the sampling switch to the filtering unit for storage.
In some embodiments of the present disclosure, the filtering unit includes: a filtering resistor, where an end of the filtering resistor is connected to a first end of the filtering unit, and another end of the filtering resistor is connected to a second end of the filtering unit; and a storage capacitor, where an end of the storage capacitor is connected to the second end of the filtering unit, and another end of the storage capacitor is grounded.
In some embodiments of the present disclosure, the gating module includes a plurality of gating switches, where the plurality of gating switches are provided in one-to-one correspondence with the plurality of storage modules, and a control end of a gating switch receives the gating control signal; where a ratio of a time constant formed by an off-resistance of any gating switch and the storage capacitor to a sampling period is greater than or equal to 10/n, n is a number of gain branches included in the current conversion module, and n is a positive integer greater than or equal to 1.
In some embodiments of the present disclosure, the control module is further configured to: obtain a digital voltage signal corresponding to a voltage sensing signal output by each gain branch; and select a digital voltage signal in a preset voltage range as an effective voltage signal.
In some embodiments of the present disclosure, the plurality of sensing modules includes a first sensing module, a second sensing module, a third sensing module and a fourth sensing module; the first sensing module is configured to sense ambient red light, the second sensing module is configured to sense ambient green light, the third sensing module is configured to sense ambient blue light, and the fourth sensing module is configured to sense white light.
According to a second aspect of the present disclosure, there is further provided a detection method for ambient light, applied to the detection circuit for ambient light according to any embodiment of the present disclosure; the method is performed by a control module; and the method includes: controlling each current conversion module to be turned on synchronously in a sampling period; outputting a sampling control signal of an on-level synchronously to each storage module within an on-duration of the current conversion module, to control each storage module to store a voltage sensing signal output by a current conversion module connected to the storage module; and obtaining a voltage sensing signal stored in each storage module respectively, and preforming preprocessing on each voltage sensing signal.
In some embodiments of the present disclosure, the method includes: controlling each current conversion module to be turned on synchronously in a sampling period; outputting a sampling control signal synchronously to each storage module within an on-duration of the current conversion module, to control each storage module to store a voltage sensing signal output by a current conversion module connected to the storage module; outputting a gating control signal to the gating module to transmit a voltage sensing signal stored in a corresponding storage module to the analog-to-digital conversion module, where the analog-to-digital conversion module is configured to convert the obtained voltage sensing signal into a digital voltage signal; performing selection on the digital voltage signal; and, if the digital voltage signal is an effective voltage signal, storing the effective voltage signal.
In some embodiments of the present disclosure, the method includes: outputting a gain control signal in a time-sharing manner according to a preset time sequence in a sampling period, to turn on each gain branch in a time-sharing manner; after outputting a gain control signal of an on-level for a preset duration, outputting a sampling control signal of an on-level synchronously to each storage module to control each storage module to store a voltage sensing signal output by a current conversion module connected to the storage module, where the on-level of the sampling control signal at least partially overlaps with the on-level of the gain control signal; outputting a gating control signal to the gating module to transmit a voltage sensing signal stored in a corresponding storage module to the analog-to-digital conversion module, where the obtained voltage sensing signal is converted into a digital voltage signal by the analog-to-digital conversion module; performing selection on the digital voltage signal; and, if the digital voltage signal is an effective voltage signal, storing the effective voltage signal
According to a third aspect of the present disclosure, there is further provided a display apparatus, including the detection circuit for ambient light according to any embodiment of the present disclosure.
According to the detection circuit for ambient light provided by the present disclosure, each sensing module outputs a current sensing signal based on the collected ambient light; a corresponding current conversion module converts the current sensing signal into a corresponding voltage sensing signal and outputs the voltage sensing signal to a storage module connected to the current conversion module; and, a control module outputs a sampling control signal synchronously to each storage module to control each storage module to be turned on synchronously. Therefore, each storage module can synchronously store the ambient light signal collected by a corresponding sensing module at the same moment; that is, the synchronous collection of each sensing module is realized. Thus, the problem that the light signals of different sensing modules are not synchronized in the related art is solved.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure.
The accompanying drawings here, which are incorporated in and constitute a part of the description, illustrate embodiments consistent with the present disclosure, and together with the description serve to explain the principles of the present disclosure. Obviously, the accompanying drawings in the following description are some embodiments of the present disclosure; and, for those of ordinary skill in the art, other drawings can also be obtained from these drawings without creative efforts.
Example embodiments will now be described more fully with reference to the accompanying drawings. Example embodiments, however, can be implemented in various forms and should not be construed as limited to the embodiments set forth herein; by contrast, these embodiments are provided so that the present disclosure will be thorough and complete, and will fully convey the concept of example embodiments to those skilled in the art. The matching reference numerals in the drawings denote the matching or similar structures, and thus their detailed descriptions will be omitted. In addition, the drawings are merely schematic illustrations of the present disclosure and are not necessarily drawn to scale.
According to the detection circuit for ambient light provided by the present disclosure, each sensing module 10 outputs a current sensing signal Id 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 the voltage sensing signal Vs to the storage module 30 connected to the current conversion module 20; and the control module 40 outputs a sampling control signal SMPL synchronously to each storage module 30 to control each storage module 30 to be turned on synchronously. Therefore, each storage module 30 can synchronously store the ambient light signal collected by the corresponding sensing module 10 at the same moment; that is, the synchronous collection of each sensing module is realized. Thus, the problem that the light signals of different sensing modules 10 are not synchronized in the related art is solved.
As shown in
After the current sensing signal Id output by each sensing module 10 is converted into a corresponding voltage sensing signal Vs through the current conversion module 20, the control module 40 outputs a sampling control signal SMPL to each storage module 30 to turn on the communication path between each storage module 30 and the corresponding current conversion module 20, so that the voltage sensing signal Vs output by the current conversion module 20 can be transmitted to the storage module 30 for storage. The control module 40 further outputs the gating control signal MX for controlling the gating module 50 to turn on the storage module 30 and the analog-to-digital conversion module 60 in sequence, so as to convert the voltage sensing signal Vs stored in each storage module 30 into the digital voltage signal Vd through the analog-to-digital conversion module 60 and output the digital voltage signal Vd to the control module 40, and the digital voltage signal Vd is stored by the control module 40. The display apparatus may perform display adjustment based on the stored digital voltage signal Vd. For example, the related control device of the display apparatus may access the control module 40 through a serial interface, and adjust the display brightness according to the stored digital voltage signal Vd. For example, according to the level signal, it may be determined that the current ambient light is relatively darker, and then, the display brightness may be reduced, or the like.
Correspondingly, as shown in
The various functional modules in the detection circuit are further described below with reference to the accompanying drawings.
As shown in
As shown in
Among them, the signal amplification unit may include an operational amplifier OP, an input end of the operational amplifier OP is connected to the reference voltage end, and the other input end of the operational amplifier OP is connected to the output end of the corresponding sensing module 10. The feedback unit may include a feedback capacitor Cf, and the feedback capacitor Cf is connected in parallel to two ends of the gain branches. The gain adjustment unit may include a plurality of gain branches connected in parallel; each gain branch may include a gain resistor Rg and a gain control switch Tg; the gain resistor Rg is connected in series with the gain control switch Tg; and the gain control switch Tg may be configured to turn on the corresponding gain branch in response to a gain control signal Gain, so as to adjust the gain coefficient of the gain adjustment unit. The gain coefficient may be understood as an magnification times to 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 magnitude relationship of each gain resistor Rg, each gain level of the gain adjustment unit may be changed step by step according to a certain ratio. For example, as shown in
For example, the gain adjustment unit may include four gain branches, and each gain branch includes a gain resistor Rg and a gain control switch Tg connected in series; the gain resistors Rg of different gain branches are different; and when the gain control switch Tg of a certain gain branch is turned on, the gain branch is turned on, so that the gain adjustment unit has 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 may output the gain control signal Gain of the on-level sequentially in a time-sharing manner to turn on each gain branch in the time-sharing manner. The current conversion module 20 outputs the voltage sensing signal Vs of the corresponding size according to the gain coefficient of the turned-on gain branch. Obviously, in the case that the gain adjustment unit has the four gain branches mentioned above, the current conversion module 20 may output voltage sensing signals Vs with four different gain magnitudes. It can be understood that the on-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, the on-level of the gain control signal Gain is a high level.
As shown in
As described above, the sensing module 10 may be a photoelectric sensor. Taking
For example, as shown in
In some embodiments, in any gain branch, the ratio of the on-resistance of the gain control switch Tg to the gain resistor Rg connected to the gain control switch Tg is less than or equal to 1%, such as 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, or the like. For example, as shown in
In addition, in some embodiments, in any gain branch, the ratio of the leakage current of the gain control switch Tg to the sensing current of the sensing module 10 connected to the gain control switch Tg is less than or equal to 1%. For example, it may be 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, or the like. For example, as shown in
As described above, the same gain branch in different current conversion modules 20 of the present disclosure may multiplex with the same gain control signal Gain, so that different current conversion modules 20 may output the voltage sensing signal Vs of the same gain level at the same moment. The same gain branch is the gain branch with the same gain coefficient.
For example,
It should be understood that the duration of each sampling sub-period in
For example, the on-duration of the gain control signal corresponding to the gain branch with a relatively larger gain resistance can be set to be relatively larger, and the on-level duration of the gain control signal corresponding to the gain branch with a relatively smaller gain resistance is set to be relatively smaller. The advantage of such setting is that, when the gain resistance is relatively larger, by setting the on-level duration of the gain control signal of the gain branch to be relatively longer, the sensing voltage signal of the gain branch can be fully released, thus preventing the gain resistor and the operational amplifier from self-excited oscillation. As shown in
In addition, as described above, the storage module 30 is in one-to-one correspondence 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 may output the sampling control signal SMPL of the on-level synchronously to each storage module 30 to turn on each storage module 30 synchronously, so that each storage module 30 can store the voltage sensing signal Vs at the same moment.
The control module 40 may output the sampling control signal SMPL of the on-level within the on-level duration of the gain control signal Gain, so that the detection circuit may control the respective storage module 30 to store the voltage sensing signal Vs corresponding to the light signal at the same moment when performing light signal collection according to a certain gain. For example, after the fourth gain control signal Gain4 of the on-level is output, the control module 40 may output the sampling control signal SMPL of the on-level after a preset duration to turn on the connection between each storage module 30 and the corresponding current conversion module 20, thus controlling each storage module 30 to synchronously store the voltage sensing signal after each sensing module 10 performs signal amplification by using the same gain level. In the present disclosure, the on-level of the sampling control signal SMPL output by the control module 40 is later than the on-level of the gain control signal Gain, so that the voltage sensing signal Vs of the previous sampling sub-period stored in the feedback capacitor Cf can be fully released, thus ensuring that the voltage sensing signal Vs stored in the feedback capacitor Cf reflects the light signal at the current sampling moment more accurately. It can be understood that the on-level of the sampling control signal SMPL varies with the type of the sampling switch Ts. For example, when the sampling switch Ts is an N-type transistor switch, the on-level of the sampling control signal SMPL is a high level.
As shown in
Among them, as described above, in some embodiments, the current conversion module 20 outputs a voltage sensing signal Vs through the operational amplifier OP. The sampling switch Ts is connected in series between the filtering unit 35 and the corresponding operational amplifier OP, so that the sampling switch Ts may respond to the sampling control signal SMPL to control the filtering unit 35 to be connected to the operational amplifier OP at the corresponding position or disconnected from the operational amplifier OP at the corresponding position. When the sampling control signal SMPL is an on-level, the sampling switch Ts is turned on, and the filtering unit 35 is connected to the operational amplifier OP at the corresponding position to obtain the voltage sensing signal Vs output by the operational amplifier OP for storage. When the sampling control signal SMPL is not an on-level, the sampling switch Ts is disconnected, and the filtering unit 35 is disconnected from the operational amplifier OP at the corresponding position.
The filtering unit 35 may include a filtering resistor R and a storage capacitor C, where the storage capacitor and the filtering resistor form a low-pass filter. One end of the filtering resistor R is connected to the first end of the filtering unit 35, and the other end of the filtering resistor R is connected to the second end of the filtering unit 35. One end of the storage (filtering) capacitor C is connected to the second end 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 may 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, and the control module 40 may further control the gating module 50 to be turned on, so as to output the voltage sensing signal Vs stored in the storage capacitor C to the analog-to-digital conversion module 60 and convert it into the digital voltage signal Vd.
As shown in
In addition, as shown in
In some embodiments, the gating module 50 may include a plurality of gating switches MUX, and the gating switch MUX may be, for example, a transistor switch. The number of gating switches MUX may be in one-to-one correspondence with the number of storage modules 30; that is, a gating switch MUX is connected to a storage module 30. When the gating switch MUX is turned on, the voltage sensing signal Vs stored in the storage module 30 connected to the gating switch MUX may be transmitted to the analog-to-digital conversion module 60. For example, as shown in
In some embodiments, 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 conversion module 60, the second gating switch MUX2 is connected between the second storage module 32 and the analog-to-digital conversion module 60, the third gating switch MUX3 is connected between the third storage module 33 and the analog-to-digital conversion module 60, and the fourth gating switch MUX 4 is connected between the fourth storage module 34 and the analog-to-digital conversion module 60. When the first gating switch MUX1 is turned on, the voltage sensing signal Vs stored in the first storage module 31 may be transmitted to the analog-to-digital conversion module 60. When the second gating switch MUX2 is turned on, the voltage sensing signal Vs stored in the second storage module 32 may be transmitted to the analog-to-digital conversion module 60, and so on. The control module 40 sequentially outputs the gating control signals MX, so that the analog-to-digital conversion module 60 can obtain the voltage sensing signal Vs of each storage module 30 respectively.
In some embodiments, the ratio of the time constant T formed by the off-resistance of any gating switch MUX and the storage capacitor to a sampling period may be greater than or equal to 10/n, 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, n may be 10, 11, 12, 13, 14, or 15. Here, a sampling period includes four sampling sub-periods in
In some embodiments, the gating switch MUX may be implemented by a transistor, and the off-resistance of the gating switch MUX may be increased by increasing the width-to-length ratio of the channel region of the transistor.
The analog-to-digital conversion module 60 in the present disclosure may be an integrated device, for example, may be an analog-to-digital conversion chip, and the sampling precision of the analog-to-digital conversion module 60 needs to match the use requirements of the display apparatus. The specific process and principle of the analog-to-digital conversion module 60 will not be described in detail here. The level-shift module 70 may shift the control signal generated by the control module 40 into a high/low level signal (VGH/VGL) to drive the gain control switch Tg, the sampling switch Ts, and the gating switch MUX.
In some embodiments, the control module 40 may be further configured to perform selection on 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 may compare the digital voltage signal Vd of each gain level with the two end value voltages of a preset voltage range. When the digital voltage signal Vd is within the preset voltage range, the control module 40 may store the digital voltage signal Vd as the effective voltage signal of the current sampling period. The control module 40 performs sampling for the next sampling sub-period, and performs selection on the digital voltage signal Vd by using the same method. In addition, it should be understood that, in a sampling period, when there are digital voltage signals Vd with more than one gain level within the preset voltage range, the control module 40 may store the digital voltage signal Vd with the maximum value as the effective voltage signal of the current sampling period. It should be understood that the above method for determining the effective voltage signal is merely an exemplary description, and should not be construed as a limitation to the present disclosure, and in other embodiments of the present disclosure, the effective voltage signal of each sampling period may also be determined in other manners.
In S110, each current conversion module is controlled to be turned on synchronously in a sampling period.
In S120, a sampling control signal is output synchronously to each storage module within an on-duration of the current conversion module, so as to control each storage module to store a voltage sensing signal output by the current conversion module connected to the storage module.
In S130, the voltage sensing signal stored in each storage module is obtain respectively, and preprocessing is performed on each voltage sensing signal.
According to the detection method of the present disclosure, in a sampling period, the control module may control the current conversion module connected to each sensing module to be turned on synchronously, so that each current sensing module can output a voltage sensing signal based on a same moment. The control module further outputs a sampling control signal SMPL synchronously to each storage module, and controls each storage module to store the voltage sensing signal output by the current conversion module connected to the storage module, so that it may be ensured that the voltage sensing signal stored in each storage module is the voltage sensing signal at the same moment, thus solving the problem that the light signals of different sensing modules are not synchronized in the related art.
The above steps of the example embodiment will be described in more detail below.
In step S110, the control module controls each current conversion module to be turned on synchronously in a sampling period.
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, an input end of the operational amplifier is connected to a reference voltage end, and the other input end of the operational amplifier is connected to an output end of the corresponding sensing module. The gain adjustment unit may include a plurality of gain branches connected in parallel, each gain branch may include a gain resistor and a gain control switch, the gain resistor is connected in series with the gain control switch, and the gain control switch may be configured 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, and the feedback capacitor is connected in parallel to two ends of the gain branches. In a sampling period, the control module may output the gain control signal Gain of the on-level to the gain control switch according to the preset time sequence as shown in
In step S120, within the on-duration of the current conversion module, the control module outputs the sampling control signal SMPL of the on-level synchronously to each storage module to control each storage module to store the voltage sensing signal output by the current conversion module connected to the storage module.
For example, the control module may output the sampling control signal SMPL in a time-sharing manner as shown in
In other words, after outputting the gain control signal Gain of the on-level for a preset duration, the control module may output the sampling control signal SMPL of the on-level synchronously to each storage module to control each storage module to store the voltage sensing signal output by the current conversion module connected to the storage module. Among them, the on-level of the sampling control signal SMPL at least partially overlaps with the on-level of the gain control signal Gain.
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, the sampling switch is connected in series between the filtering unit and the corresponding operational amplifier, and the control end of the sampling switch receives the sampling control signal SMPL; where, in response to the sampling control signal SMPL, the sampling switch transmits the voltage sensing signal output by the conversion unit connected to the sampling switch to the filtering unit for storage. The filtering unit may be formed by a filtering resistor and a storage capacitor. When the sampling switch obtains the sampling control signal SMPL of the on-level, the sampling switch is turned on to connect the filtering unit to the output end of the operational amplifier at the corresponding position, so that the voltage sensing signal at the current sampling moment can be stored. Since each sampling switch obtains the sampling control signal SMPL of the on-level synchronously, each filtering unit can store the voltage sensing signal at the current moment synchronously.
In step S130, the control module obtains the voltage sensing signal stored in each storage module respectively, and performs preprocessing on each voltage sensing signal.
As described above, the detection circuit may further include a gating module, an analog-to-digital conversion module and a level-shift module. Among them, the gating module is connected in series between the storage module and the control module, and the gating module may be configured to turn on the communication path between the corresponding storage module and the control module in response to the gating control signal MX output by the control module. The analog-to-digital conversion module is connected in series between the gating module and the control module, and the analog-to-digital conversion module may be configured to convert the obtained voltage sensing signal into a digital voltage signal for output. The level-shift module is connected to the control module, and the level-shift module may be configured to shift each control signal (including the sampling control signal SMPL, the gain control signal Gain, and the gating control signal MX) of the control module into a corresponding level signal and output the level signal to the corresponding switch module.
On this basis, step S130 may include the following steps.
A gating control signal MX is output to the gating module, so as 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 obtained voltage sensing signal into a digital voltage signal.
Selection is performed on the digital voltage signal.
If the digital voltage signal is an effective voltage signal, the effective voltage signal is stored.
Among them, the gating module may include a plurality of gating switches MUX. The number of gating switches MUX is in one-to-one correspondence with the number of the storage modules; that is, a gating switch MUX controls the connection between a storage module and the analog-to-digital conversion module. The control module may sequentially output the gating control signal MX of the on-level to each gating switch MUX to control each storage module to sequentially output the voltage sensing signal stored therein to the analog-to-digital conversion module, where the voltage sensing signal is converted into a digital voltage signal by analog-to-digital conversion module.
It should be noted that the control module of the present disclosure may perform selection on the obtained digital voltage signal, that is, to perform selection on the digital voltage signal of each gain level. When the digital voltage signal is within the preset voltage range, the control module determines that the digital voltage signal is an effective voltage signal, and stores the effective voltage signal. When the digital voltage signal is not within the preset 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 more than one gain level are within the preset voltage range, the control module may store a digital voltage signal having the maximum value as the effective voltage signal of the current sampling period.
An external circuit may directly read the data in the specified memory through a serial interface, and the serial interface may be, for example, an I2C serial interface or a SPI serial interface, or other serial interfaces.
The present disclosure further provides a display apparatus, which may include the detection circuit for ambient light described in any of the above embodiments. The display apparatus may be, for example, a mobile phone, a PAD, or the like. The display apparatus may perform display and adjustment on the display apparatus through the ambient light detected by the detection circuit for ambient light, for example, may automatically adjust the display brightness of the display apparatus according to the ambient light.
Other embodiments of the present disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the present disclosure. The present disclosure is intended to cover any variations, uses, or adaptations of the present disclosure following the general principles of the present disclosure and including the common knowledge and conventional technical means in the art not disclosed in the present disclosure. It is intended that the description and embodiments are considered as examples only, with a true scope and spirit of the present disclosure being indicated by the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202210903883.1 | Jul 2022 | CN | national |
The present application is a U.S. national stage of International Application No. PCT/CN2023/109405, filed on Jul. 26, 2023, and claims priority to Chinese Patent Application No. 202210903883.1 entitled “Detection circuit for ambient light, detection method for ambient light, and display apparatus”, filed on Jul. 28, 2022, and the entire contents of both of which are incorporated herein by reference.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/CN2023/109405 | 7/26/2023 | WO |
