Driving circuit and electronic device

Abstract

The application discloses a driving circuit and electronic equipment, the circuit comprises: a first driving module, a timeout protection module and a first light emitting module; the first current output end of the first driving module is connected with the first light emitting module, and the enable end of the first driving module is connected with the timeout protection module; in the case that the voltage value output by the timeout protection module to the enable end is less than a first voltage threshold, the first driving module stops outputting current to the first light emitting module.

Description

Technical Field

[0001] This application relates to the field of electronic product technology, and in particular to a driving circuit and electronic device. Background Technology

[0002] Camera modules in electronic devices typically include light-emitting modules, which can be used for functions such as flashlights, strobe lights, and LEDs. Currently, when driving these light-emitting modules, they often operate at high currents. If the electronic device encounters special circumstances (such as freezing or crashing), the light-emitting module can easily burn out. Summary of the Invention

[0003] This application provides a driving circuit and electronic device to solve the problem that the light-emitting module in the current camera module is prone to burn-out when it operates under high current.

[0004] To solve the above-mentioned technical problems, this application is implemented as follows:

[0005] In a first aspect, embodiments of this application provide a driving circuit, including: a first driving module, an overtime protection module, and a first light-emitting module;

[0006] The first current output terminal of the first driving module is connected to the first light-emitting module, and the enable terminal of the first driving module is connected to the timeout protection module.

[0007] If the voltage value output by the timeout protection module to the enable terminal is less than the first voltage threshold, the first driving module stops outputting current to the first light-emitting module.

[0008] Secondly, embodiments of this application also provide an electronic device, including the driving circuit described above.

[0009] In the above-described solution of this application, by setting an overtime protection module at the enable terminal of the first driving module, when the first driving module outputs current to the first light-emitting module and the first light-emitting module operates in the first light-emitting mode with a large current, the overtime protection module can be used to output a voltage value to the enable terminal that is less than a first voltage threshold, thereby causing the first driving module to stop outputting current to the first light-emitting module, that is, the first light-emitting module stops working, so as to avoid the problem of the first light-emitting module burning out due to prolonged operation at a high current. Attached Figure Description

[0010] Figure 1A One of the schematic diagrams illustrating the operating current of the light-emitting unit in an embodiment of this application;

[0011] Figure 1B A second schematic diagram illustrating the operating current of the light-emitting unit in an embodiment of this application;

[0012] Figure 1C Schematic diagram three illustrating the operating current of the light-emitting unit in an embodiment of this application;

[0013] Figure 1D Fourth schematic diagram illustrating the operating current of the light-emitting unit in an embodiment of this application;

[0014] Figure 1E Fifth schematic diagram illustrating the operating current of the light-emitting unit in an embodiment of this application;

[0015] Figure 2 This is a schematic diagram of one of the driving circuits in an embodiment of this application;

[0016] Figure 3 A second schematic diagram of the driving circuit according to an embodiment of this application;

[0017] Figure 4 The third schematic diagram of the driving circuit in an embodiment of this application;

[0018] Figure 5 Fourth schematic diagram of the driving circuit according to an embodiment of this application;

[0019] Figure 6 This is a flowchart illustrating the driving logic of the light-emitting unit in an embodiment of this application.

[0020] Figure 7 A schematic diagram illustrating the voltage change of the enable terminal over time in an embodiment of this application;

[0021] Figure 8 This is a schematic diagram showing the correspondence between the voltage of the enable terminal and the driving current of the first light emission mode in an embodiment of this application. Detailed Implementation

[0022] Exemplary embodiments of the present application will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present application are shown in the drawings, it should be understood that the present application may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this application will be thorough and complete, and will fully convey the scope of the present application to those skilled in the art.

[0023] The following describes the relevant technologies involved in this application:

[0024] There are three modes for driving lights in electronic devices:

[0025] 1. Continuous illumination mode (Torch mode);

[0026] Torch mode can be used for short-term, constant-brightness photography scenarios, with the corresponding current-driven waveform as follows: Figure 1AAs shown; for example: the current max can be 600mA, t1=3s, t2=2s. The current and duration values ​​here are just examples, and the embodiments of this application are not limited thereto.

[0027] Torch mode can also be used in light-emitting scenarios, with the corresponding current-driven waveform as follows: Figure 1B As shown; for example, the maximum current can be 228mA, and the light-emitting unit is turned on at time T1; the current value here is only an example, and the embodiments of this application are not limited thereto.

[0028] Torch mode can also be used in flashlight scenarios, with the corresponding current-driven waveform as follows: Figure 1C As shown; for example: at time T1, turning on the first brightness level of the flashlight corresponds to a current of 50mA; at time T2, turning on the second brightness level of the flashlight corresponds to a current of 100mA; at time T3, turning on the third brightness level of the flashlight corresponds to a current of 150mA; at time T4, turning on the fourth brightness level of the flashlight corresponds to a current of 200mA; the current values ​​and the number of brightness levels of the flashlight are only examples, and the embodiments of this application are not limited thereto.

[0029] When taking photos with electronic devices, the short-term constant-on shooting scenario under Torch mode is frequently used. If a sudden device freeze or crash occurs during this scenario, the existing Torch mode driver circuit lacks hardware protection, potentially damaging the light-emitting unit. Alternatively, in the short-term constant-on shooting scenario under Torch mode, if the driving current to the light-emitting unit increases, the junction temperature limit in Torch mode is limited. Exceeding this limit will eventually cause damage to the light-emitting unit. Or, in the event of a sudden device freeze or crash during the short-term constant-on shooting scenario, the unpredictable shutdown time of the driving light-emitting unit may exceed its maximum duration, also resulting in damage.

[0030] 2. Flash mode;

[0031] Flash mode can be used for professional photography flashing or third-party flashing scenarios. The corresponding current drive waveform is as follows: Figure 1D As shown; for example: the current corresponding to t1 is 200mA, which represents the pre-flash stage; the current corresponding to t2 is 1.05A, which represents the main flash stage; the current values ​​here are only examples, and the embodiments of this application are not limited thereto.

[0032] When taking pictures with electronic devices, although there is a large instantaneous current in Flash mode, its working time is short, usually 1 to 2 seconds. Therefore, the light-emitting unit is usually not easy to burn out in Flash mode.

[0033] 3. Three-primary-color emission mode (RGB mode);

[0034] In RGB mode, it can be used for breathing light scenarios, and the corresponding current drive waveform is as follows: Figure 1E As shown; for example, the driving current for the breathing light mode is 1.41mA. Of course, the current value here is only an example, and the embodiments of this application are not limited thereto.

[0035] Currently, the driving circuits of camera modules typically do not support the breathing light function.

[0036] This application provides a driving circuit and electronic device to solve the problems that the light-emitting unit configured in the current camera module does not support the breathing light function, and the light-emitting unit is prone to burn-out when working in flash mode.

[0037] like Figures 2 to 5 As shown, this application embodiment provides a driving circuit, including: a first driving module 1, an overtime protection module 2, and a first light-emitting module 3;

[0038] The first current output terminal Out1 of the first driving module 1 is connected to the first light-emitting module 3, and the enable terminal EN of the first driving module 1 is connected to the timeout protection module 2.

[0039] If the voltage value output by the overtime protection module 2 to the enable terminal EN is less than the first voltage threshold, the first drive module 1 stops outputting current to the first light-emitting module 3.

[0040] Optionally, the first drive module 1 includes an enable unit, which may include a resistor. One end of the resistor is connected to the power supply terminal of the first drive module 1, and the other end is connected to the enable terminal EN.

[0041] For example, when the voltage value of the input enable terminal EN is greater than the second voltage threshold, the first driving module 1 outputs current to the first light-emitting module 3, and the first light-emitting module 3 operates in the first light-emitting mode. For example, the second voltage threshold can be a high level (i.e., greater than the second voltage threshold), and the first light-emitting mode can be a flash mode, or a Torch mode, or a short-long-bright light-emitting mode under the Torch mode, etc. The embodiments of this application are not limited thereto.

[0042] For example, the first light-emitting mode can refer to the mode in which the first light-emitting module 3 emits light with short pulses of high brightness. In the first light-emitting mode, the first light-emitting module 3 has a larger operating current, which is suitable for use in low-light environments. It can freeze moving objects instantly or provide effective supplementary light when shooting distant scenes.

[0043] Optionally, the first light-emitting module 3 may include one or more light-emitting elements, such as light-emitting diodes. One light-emitting element in the first light-emitting module 3 may correspond to one current output terminal in the first driving module 1 (for example, the number of first current output terminals Out1 may be multiple, and multiple first current output terminals Out1 may correspond one-to-one with multiple light-emitting elements included in the first light-emitting module 3), etc. The embodiments of this application are not limited thereto.

[0044] In this embodiment, by setting an overtime protection module 2 at the enable terminal EN of the first driving module 1, when the first driving module 1 outputs current to the first light-emitting module 3 and the first light-emitting module 3 operates in a first light-emitting mode with a large current, the overtime protection module 2 can be used to output a voltage value to the enable terminal EN that is less than a first voltage threshold, thereby causing the first driving module 1 to stop outputting current to the first light-emitting module 3, that is, the first light-emitting module 3 stops working, so as to avoid the problem of the first light-emitting module 3 burning out due to prolonged operation at a high current.

[0045] Optionally, the driving circuit further includes: a second light-emitting module 5; the second current output terminal Out2 of the first driving module 1 is connected to the second light-emitting module 5;

[0046] When the first current output terminal Out1 outputs current to the first light-emitting module 3, the first light-emitting module 3 operates in the first light-emitting mode;

[0047] When the second current output terminal Out2 outputs current to the second light-emitting module 5, the second light-emitting module 5 operates in the second light-emitting mode.

[0048] For example, the second lighting mode can be RGB mode or a breathing light mode. Specifically, it refers to the brightness of the second lighting module 5 smoothly and gradually changing according to a preset cycle, cyclically changing from dark to bright and then from bright to dark. The second lighting mode can serve as a reminder function for sleep standby.

[0049] Optionally, the second light-emitting module 5 may include one or more light-emitting elements, such as light-emitting diodes. One light-emitting element in the second light-emitting module 5 may correspond to one current output terminal of the first driving module 1 (for example, the number of second current output terminals Out2 may be multiple, and multiple second current output terminals Out2 may correspond one-to-one with multiple light-emitting elements included in the second light-emitting module 5).

[0050] For example, the first driving module 1 may include multiple current sources I1, I2, and I3. Current source I1 is used to drive the first light-emitting module 3 to work in the first light-emitting mode; current sources I2 and I3 may be used to drive the second light-emitting module 5 to work in the second light-emitting mode, etc. The embodiments of this application are not limited thereto.

[0051] Optionally, the first driving module 1 may be a flash driver chip in a power management integrated circuit (PMIC), and the first driving module 1 has a channel for a second light emission mode (or breathing light function).

[0052] In this embodiment, in addition to driving the first light-emitting module 3 to work in the first light-emitting mode through the first driving module 1, the second light-emitting module 5 can also be driven to work in the second light-emitting mode through the channel of the second light-emitting mode (or breathing light function) inherent in the first driving module 1 itself, thereby realizing the configuration of breathing light function in the camera module and solving the problem that the light-emitting unit configured in the current camera module does not support breathing light function.

[0053] Optionally, the driving circuit further includes: a second driving module 4 and a first current protection module 8; the third current output terminal Out3 of the second driving module 4 is connected to the second light-emitting module 5; the second current output terminal Out2 is connected to the second light-emitting module 5 and the third current output terminal Out3 respectively through the first current protection module 8.

[0054] When the third current output terminal Out3 outputs current to the second light-emitting module 5, the second light-emitting module 5 operates in the third light-emitting mode.

[0055] For example, the third light-emitting mode can be called Torch mode, or a low-current light-emitting mode under Torch mode, or a constant-on mode under Torch mode, or a soft light mode, etc. The third light-emitting mode can refer to the mode in which the second light-emitting module 5 is driven to emit light continuously at low power. The light emitted by the second light-emitting module 5 can be evenly diffused by the soft light component to achieve a soft light effect. For example, in this third light-emitting mode, the second light-emitting module 5 is in a constant-on mode, which is more suitable for portrait photography, making the portrait in the picture more delicate and natural.

[0056] For example, the second light-emitting module 5 may include one or more light-emitting elements, such as light-emitting diodes. One light-emitting element in the second light-emitting module 5 may correspond to one current output terminal in the second driving module 4 (for example, the number of third current output terminals Out3 may be multiple, and multiple third current output terminals Out3 may correspond one-to-one with multiple light-emitting elements included in the second driving module 4).

[0057] For example, the second driving module 4 may include multiple current sources I4 and I5, which are used to drive the second light-emitting module 5 to work in the third light-emitting mode, etc. The embodiments of this application are not limited thereto.

[0058] In this embodiment, the first current protection module 8 is used to ensure that the current output by the third current output terminal Out3 can be transmitted to the second light-emitting module 5, and to prevent the current of the third current output terminal Out3 from flowing back to the second current output terminal Out2, thus playing an isolation role.

[0059] For example, the first current protection module 8 includes one or more diodes. Specifically, the number of diodes can be set based on the number of the third current output terminal Out3 and the second current output terminal Out2. See also: Figures 2 to 5 As shown, the second light-emitting module 5 includes two third current output terminals Out3 and two second current output terminals Out2. The corresponding first current protection module 8 includes two diodes, such as a first diode D1 and a second diode D2. The anode of each diode (i.e., the first diode D1 and the second diode D2) is connected to the second current output terminal Out2, and the cathode of each diode (i.e., the first diode D1 and the second diode D2) is connected to the second light-emitting module 5 and the third current output terminal Out3, respectively. This prevents the current from the third current output terminal Out3 from flowing back into the second current output terminal Out2, thus providing isolation.

[0060] For example, the third illumination mode is a low-current, constant-on mode, similar to a flashlight function. Similarly, the operating current of the second illumination module 5 in the second illumination mode is relatively low, resulting in a small temperature rise. Therefore, protection functions can be temporarily disregarded for the third and second illumination modes. However, the first illumination mode uses a short-duration, constant-on mode under Torch mode. In this mode, the operating current of the first illumination module 3 is relatively high, leading to a higher junction temperature. If this temperature exceeds the allowable operating temperature of a single first illumination module 3, it will pose a reliability risk. Therefore, this embodiment of the application considers limiting the illumination time of the first illumination module 3.

[0061] Optionally, see Figure 2 As shown, the driving circuit also includes: a clock module 6; the clock module 6 is connected to the first driving module 1;

[0062] The timeout protection module 2 includes: a first pull-down unit 21, the output terminal GPIO of the first pull-down unit 21 is connected to the enable terminal EN.

[0063] When the first drive module 1 detects that the current value output by the first current output terminal Out1 is greater than the first current threshold, it outputs a first command to the clock module 6. The first command is used to trigger the clock module 6 to start timing.

[0064] When the timing duration of the clock module 6 exceeds the first duration threshold, the clock module 6 sends a second instruction to the first drive module 1. The second instruction is used to make the voltage value of the input enable terminal EN of the first pull-down unit 21 of the first drive module 1 less than the first voltage threshold.

[0065] For example, the first drive module 1 is equipped with a current detection unit. For instance, the current source I1 corresponding to the first current output terminal Out1 in the first drive module 1 may be equipped with a current detection unit, which can be used to self-detect the magnitude of its output current value. In this way, the first drive module 1 can determine the current value output by the first current output terminal Out1. When the first drive module 1 detects that the current value output by the first current output terminal Out1 is greater than a first current threshold, it can output a first command to the clock module 6 to trigger the clock module 6 to start timing.

[0066] For example, the clock module 6 can be a Power Management Kit (PMK). When the first driving module 1 triggers the clock module 6 to start timing, the timing function can be triggered by the internal Peripheral System Interconnect (PSI) code of the clock module 6. This application embodiment does not impose specific limitations on the clock module 6. When the clock module 6 reaches the first duration threshold, it sends a second instruction to the first driving module 1 to notify the first driving module 1 that the timing has reached the first duration threshold, or to instruct the first driving module 1 to trigger the voltage value of the input enable terminal EN of the first pull-down unit 21 to be less than the first voltage threshold, so that the first current output terminal Out1 stops outputting current to the first light-emitting module 3, that is, the first light-emitting module 3 stops working to avoid burnout.

[0067] Optionally, the first pull-down unit 21 may be integrated inside the first driving module 1, or it may be disposed outside the first driving module 1. This embodiment of the application is not limited thereto.

[0068] Optionally, the timeout protection module 2 further includes: a first voltage divider element; the first pull-down unit 21 includes: a second voltage divider element and a first switch; the first end of the first voltage divider element is connected to the power supply terminal of the first drive module 1, and the second end of the first voltage divider element is connected to the enable terminal EN; the first end of the second voltage divider element 32 is connected to the reference ground, and the second end of the second voltage divider element is connected to the output terminal GPIO of the first drive module 1 through the first switch, and the output terminal GPIO is connected to the enable terminal EN.

[0069] When the timing duration of the clock module 6 exceeds the first duration threshold, the first drive module 1 controls the first switch to close, pulling the level of the enable terminal EN to a low level (i.e., less than the first voltage threshold).

[0070] For example, the first voltage divider element and the second voltage divider element can be implemented using voltage divider resistors, or other components such as Zener diodes or diodes can be used. The embodiments of this application are not limited to these.

[0071] For example, the first switch can be a power switch or a transistor switch, or other types of control switches, etc., and the embodiments of this application are not limited thereto.

[0072] In this embodiment, the first voltage divider element is connected in series between the power supply terminal and the enable terminal EN of the first driving module 1, and the second voltage divider element and the first switch are connected in series between the output terminal GPIO of the first driving module 1 and the reference ground. Since the output terminal GPIO of the first driving module 1 and the enable terminal EN are connected together, when the first switch is open, the voltage of the enable terminal EN is the voltage of the power supply terminal of the first driving module 1 after passing through the first voltage divider element. In this way, by reasonably selecting the type of the first voltage divider element, the voltage of the power supply terminal of the first driving module 1 after passing through the first voltage divider element satisfies the high level of enabling the first light-emitting mode (i.e., greater than the second voltage threshold), thereby ensuring that when the first switch is open, the first driving module 1 can drive the first light-emitting module 3 to work in the first light-emitting mode. When the first switch is closed, the voltage at the enable terminal EN is the voltage value on the second voltage divider after the power supply terminal of the first driving module 1 is divided by the first voltage divider and the second voltage divider. By reasonably selecting the type of the second voltage divider, the voltage on the second voltage divider after the power supply terminal of the first driving module 1 is divided by the first voltage divider and the second voltage divider satisfies the low level (i.e. less than the first voltage threshold) required to turn off the first light-emitting mode. This ensures that when the first switch is closed, the first driving module 1 can turn off the first light-emitting mode of the first light-emitting module 3.

[0073] Specifically, when the first driving module 1 determines that the current value of the first current output terminal Out1 is greater than the first current threshold, it triggers the clock module 6 to start timing. The timing function is triggered by the on-chip PSI code inside the clock module 6. When the clock module 6 reaches the time threshold, it triggers the first driving module 1 to control the first switch to close, and the level of the enable terminal EN is low (i.e., less than the first voltage threshold). That is, by pulling down the level value of the output terminal GPIO of the first driving module 1, the level value of the enable terminal EN (or Strobe pin) is synchronously pulled down, thereby controlling the hardware Strobe pin to turn off the first light-emitting mode. When the level of the enable terminal EN (or Strobe pin) is low (i.e., less than the first voltage threshold), the first light-emitting mode is turned off. Even if the electronic device experiences lag or crashes at this time, the enable terminal EN (or Strobe pin) will still shut down the output of the first driving module 1, thereby turning off the first light-emitting mode and protecting the first light-emitting module 3 from being burned out.

[0074] Optionally, the drive circuit further includes: a processor 7; the processor 7 is connected to the first drive module 1;

[0075] The processor 7 determines the first current value based on the first light intensity and outputs a third instruction to the first driving module 1. The third instruction is used to instruct the first current output terminal Out1 of the first driving module 1 to output the first current value to the first light-emitting module 3.

[0076] For example, the intensity of ambient light can be detected by a sensor, and the processor 7 can calculate the operating current of the first light-emitting module 3 based on the intensity of the ambient light. The processor 7 then sends the current level of the first light-emitting module 3 to the first driving module 1. For instance, the operating current of the first light-emitting module 3 can have multiple levels. The processor 7 sends the current level of the first light-emitting module 3 (i.e., the current of current source I1) to the first driving module 1 via the System Power Management Interface (SPMI). The first driving module 1 outputs according to the received level, as shown in [reference needed]. Figure 2 As shown, the magnitude of the current output by the current source I1 can be controlled, thereby controlling the light-emitting mode of the first light-emitting module 3.

[0077] like Figure 6 As shown, a driving flowchart for a light-emitting element is presented, specifically including:

[0078] S1: The first light-emitting module enters the first light-emitting mode, such as the short constant light scene of Torch mod;

[0079] Specifically, the application processor (AP) can detect ambient light, calculate the operating current of the first light-emitting module 3, and send it to the first driving module 1. (For example, in the short-term constant-on scenario of the Torch mod, the operating current of the first light-emitting module 3 can have multiple levels. The intensity of the ambient light is detected by the sensor, and the AP adjusts the operating current of the first light-emitting module 3 in the short-term constant-on scenario of the Torch mod according to the intensity of the ambient light. The AP can send the level of the operating current of the first light-emitting module 3 (i.e., the current of the current source I1) to the first driving module 1 through the System Power Management Interface (SPMI), and the first driving module 1 outputs according to the received level.)

[0080] S2: The first drive module detects whether the current value at the first current output terminal is greater than the first current threshold.

[0081] Specifically, the first driving module 1 determines the operating current of the first light-emitting module 3 under the Torch mode short-term and long-term illumination scenario. If the current at the first current output terminal Out1 is less than the first current threshold Imin, the first light-emitting module 3 operates normally in the first light-emitting mode, and executes step S5 when the first light-emitting mode needs to be turned off; if the current at the first current output terminal Out1 is greater than the first current threshold Imin, then executes step S3.

[0082] In step S2, since not all operating current settings pose a risk of burning out the first light-emitting module 3, but only when the operating current is high and the module operates for a long time will the junction temperature of the first light-emitting module 3 exceed the limit, the magnitude of the current output by the current source I1 can be monitored. When the current value output by the current source I1 exceeds the set first current threshold Imin, the first drive module 1 sends a command to the clock module 6 via SPMI to trigger the clock module 6 to start timing.

[0083] S3: Clock module 6 triggers the internal clock unit timer to start timing;

[0084] S4: Clock module 6 determines whether the timing duration is greater than the first duration threshold;

[0085] Specifically, the timing duration of the clock module is determined (for example, in a specific scenario, it can be used as the time when the electronic device is frozen). If the timing duration is less than the set first duration threshold Tmin, the first light-emitting module 3 works normally in the first light-emitting mode, and step S5 is executed when the first light-emitting mode needs to be turned off; if the timing duration is greater than the set first duration threshold Tmin, step S5 is executed.

[0086] S5: The first drive module controls the first switch of the first pull-down unit to close, pulling the level of the output terminal GPIO low. This pulls the level of the enable terminal EN low, and its level state is at a low level (i.e., less than the first voltage threshold). This shuts off the first drive module 1 from driving the first light-emitting module to work in the first light-emitting mode, thereby protecting the first light-emitting module 3 from being burned out.

[0087] Optionally, see Figure 3 As shown, the drive circuit also includes: processor 7; the timeout protection module 2 includes: delay circuit 22;

[0088] The processor 7 is connected to the enable terminal EN via the delay circuit 22.

[0089] When the processor 7 outputs a first enable voltage to the delay circuit 22, the voltage value output by the delay circuit 22 to the enable terminal EN is greater than the second voltage threshold, and the first driving module 1 outputs current to the first light-emitting module 3; after the first duration threshold, the voltage value output by the delay circuit 22 to the enable terminal EN is less than the first voltage threshold.

[0090] For example, when the processor 7 outputs the first enable voltage to the delay circuit 22, the delay circuit 22 can ensure that the enable terminal EN is at a high level (i.e., greater than the second voltage threshold) to enable the first driving module 1 to drive the first light-emitting module 3 to work in the first light-emitting mode. After the delay circuit 22 outputs a high level (i.e., greater than the second voltage threshold) to the enable terminal EN, the voltage value of the input enable terminal EN will gradually decrease until it reaches the first duration threshold. Then, the voltage value output to the enable terminal EN will be less than the first voltage threshold, so that the first driving module 1 stops outputting current to the first light-emitting module 3, i.e., the first light-emitting module 3 stops the first light-emitting mode.

[0091] For example, the delay circuit 22 can be a differentiating circuit. When the processor 7 outputs the first enable voltage to the delay circuit 22, the level of the enable terminal EN is high (i.e., greater than the second voltage threshold), triggering the first light-emitting mode to start. After the first enable voltage is output, within the range of the first duration threshold, the voltage of the enable terminal EN gradually decreases. This allows the voltage of the enable terminal EN to gradually decrease to a low level (i.e., less than the first voltage threshold), triggering the first light-emitting mode to stop. Therefore, the time for the voltage of the enable terminal EN to decrease to a low level (i.e., less than the first voltage threshold) can be reasonably set according to the time it takes for the first light-emitting module 3 to operate in the first light-emitting mode without being burned out, thereby preventing the first light-emitting module 3 from being burned out while operating in the flash mode.

[0092] Optionally, the timeout protection module 2 includes: a first capacitor C1 and a first resistor R1;

[0093] The first terminal of the first capacitor C1 is connected to the processor 7, the second terminal of the first capacitor C1 is connected to the first terminal of the first resistor R1, the first terminal of the first resistor R1 is also connected to the enable terminal EN, and the second terminal of the first resistor R1 is connected to the reference ground.

[0094] For example, taking the first enable voltage output by processor 7 as 1.8V, when the GPIO1 of application processor 7 outputs the first enable voltage, the voltage at point A rises from 0V to 1.8V. Since the voltage across the first capacitor C1 cannot change abruptly, the voltage at point B gradually decreases from 1.8V as the first resistor R1 charges the first capacitor C1. Specifically, the relationship between the voltage VB at point B and time t satisfies the following formula (1):

[0095] (1)

[0096] Where τ is the time constant, C1 represents the capacitance of the first capacitor, and R1 represents the resistance of the first resistor.

[0097] Based on the above formula (1), we can further obtain the following formula (2):

[0098] (2)

[0099] Where VA represents the voltage value at point A and VB represents the voltage value at point B.

[0100] like Figure 7 As shown, the curve of voltage VB at point B versus time t is presented, which is also a schematic diagram of the voltage change of the enable terminal EN over time. Figure 8As shown, the curve of the voltage VB at point B combined with the current waveform of the Torch mode is further given, which is a schematic diagram of the correspondence between the voltage of the enable terminal EN and the driving current of the first light-emitting mode. Where t1 represents the normal operating time of the first light-emitting module 3 in the short-term constant-on Torch mode (that is, the normal operating time of the first light-emitting mode); t2 represents the crash time; T3 represents the time it takes for the voltage at point B to drop to VIH; T4 represents the time it takes for the voltage at point B to drop to VIL; T_c represents the normal continuous operating time of the first light-emitting module 3; VIH represents the enable terminal EN input high level (i.e., the second voltage threshold), which is the minimum input high level allowed when the input of the logic gate is high. When the input level is higher than VIH, the enable terminal EN input level is considered to be high (i.e., the input voltage is greater than the second voltage threshold). That is, if the voltage at point B is greater than VIH, then the first driving module 1 operates normally; VIL represents the enable terminal EN input low level (i.e., the first voltage threshold), which is the maximum input low level allowed when the input of the logic gate is low. When the enable terminal EN input level is lower than VIL, the input level is considered to be low (i.e., the input voltage is less than the first voltage threshold). That is, if the voltage at point B is less than VIL, then the first driving module 1 is directly turned off, thus turning off the first light-emitting mode.

[0101] Optionally, if the voltage at point B is between VIL and VIH, it represents an intermediate state, in which case the first drive module 1 may be turned off or operate normally. Therefore, to ensure that the delay circuit 22 does not affect the normal operation of the first drive module 1, and also to ensure that the first drive module 1 is turned off under special circumstances, it is necessary to ensure that T3 > t1 and T4 < T_c. Figure 8 The time lengths shown describe the relationship, and from the above formula (2), we can deduce that the following formulas (3) and (4) must be satisfied:

[0102] >t1 (3)

[0103] <T_c (4)

[0104] Thus, based on the above formulas (3) and (4), the value ranges of C1 and R1 can be obtained. By selecting appropriate capacitance values ​​for the first capacitor C1 and resistance values ​​for the first resistor R1, the required timeout protection time can be set, and this timeout protection time must be less than the allowable duration T_c of the first light-emitting module 3. When the allowable duration T_c is exceeded, the voltage at point B needs to be completely reduced to below the voltage threshold VIL input to the enable terminal EN. Then, the first driving module 1 will directly shut down the first light-emitting mode to prevent the first light-emitting module 3 from being burned out in the first light-emitting mode due to a system crash.

[0105] Optionally, the timeout protection module 2 further includes: a first switching unit Q1; the first switching unit Q1 includes a first terminal, a second terminal and a control terminal; the first terminal is connected to the second terminal of the first capacitor C1, the second terminal is connected to the reference ground, and the control terminal is connected to the processor 7.

[0106] For example, the first switching unit Q1 can be a power switch or a transistor switch (such as a MOSFET), or other types of control switches, etc., and the embodiments of this application are not limited thereto. For example, when the electronic device is stuck or frozen, the processor 7 can control the first switching unit Q1 to close, thereby causing the first capacitor C1 to discharge quickly, ensuring that the voltage of the enable terminal EN decreases to a low level quickly, so as to turn off the first light-emitting mode, thereby preventing the first light-emitting module 3 from being burned out while operating in the first light-emitting mode.

[0107] Optionally, the timeout protection module 2 further includes: a clamping element 23; the first end of the clamping element 23 is connected to the first end of the first resistor R1, and the second end of the clamping element 23 is connected to the reference ground.

[0108] For example, the clamping element 23 can be a diode to clamp the first switching unit Q1 (such as a MOSFET) to prevent it from generating a negative voltage that could damage the first drive module 1.

[0109] Optionally, the timeout protection module 2 may further include: a fourth resistor R4 and a fifth resistor R5. The fourth resistor R4 is connected in series between the processor 7 and the first terminal of the first capacitor C1, and the fifth resistor R5 is connected in series between the enable terminal EN and the first terminal of the first resistor R1, which serves as a voltage divider protection function.

[0110] Optionally, see Figure 4 As shown, the timeout protection module 2 includes a temperature control circuit 24; when the temperature of the first light-emitting module 3 is greater than the first temperature threshold, the voltage value output by the temperature control circuit 24 to the enable terminal EN is less than the first voltage threshold.

[0111] For example, the temperature control circuit 24 can be used to detect the temperature value of the first light-emitting module 3, and when the temperature of the first light-emitting module 3 is greater than the first temperature threshold, the voltage value output by the temperature control circuit 24 to the enable terminal EN is less than the first voltage threshold, thereby turning off the first light-emitting mode.

[0112] For another example, the temperature control circuit 24 can be set close to the first light-emitting module 3 to sense the temperature change of the first light-emitting module 3. When the temperature of the first light-emitting module 3 is greater than the first temperature threshold, the temperature control circuit 24 automatically triggers the output voltage value to the enable terminal EN to be less than the first voltage threshold, thereby turning off the first light-emitting mode.

[0113] Optionally, the timeout protection module 2 includes: a second resistor R2 and a thermistor NTC; the first end of the second resistor R2 is connected to the first power supply M1, the second end of the second resistor R2 is connected to the first end of the thermistor NTC, the first end of the thermistor NTC is also connected to the enable terminal EN, and the second end of the thermistor NTC is connected to the reference ground; wherein, the thermistor NTC is located close to the first light-emitting module 3, and the resistance value of the thermistor NTC decreases as the temperature increases.

[0114] In this embodiment, the thermistor NTC is positioned close to the first light-emitting module 3. When the junction temperature of the first light-emitting module 3 rises, the temperature of the thermistor NTC also rises. When a negative temperature coefficient thermistor NTC is used, its resistance decreases as the temperature increases. Here, the second resistor R2 and the thermistor NTC form a voltage divider circuit. The thermistor NTC has a higher resistance at lower temperatures and a lower resistance at higher temperatures. Therefore, by adjusting the appropriate value of the second resistor R2 and selecting a suitable thermistor NTC based on the junction temperature of the first light-emitting module 3, the enable terminal EN can be kept at a low level (i.e., the input voltage is less than the first voltage threshold) by the voltage divider between the thermistor NTC and the second resistor R2 when the junction temperature of the first light-emitting module 3 is about to exceed the limit, thus turning off the first light-emitting mode and preventing the first light-emitting module 3 from burning out.

[0115] Optionally, the first power supply M1 supplies power in the first light-emitting mode.

[0116] For example, the first power supply M1 can be the driving power supply for the camera module, or it can be an independently set power supply, etc., and the embodiments of this application are not limited thereto. Taking the first power supply M1 as the driving power supply for the camera module as an example, the application scenario of the first light emission mode is only activated when the camera module is working. Therefore, the first power supply M1 will only be powered on when the camera module is working, that is, the first power supply M1 will only supply power in the first light emission mode. In this way, the driving power supply of the camera module can be reused, which can reduce the device overhead.

[0117] In this embodiment, an over-temperature protection scheme for the first light-emitting mode under abnormal conditions can be implemented with less hardware driver resources and power consumption, improving user experience while ensuring reliability. Optionally, multiple light-emitting modes (such as the first light-emitting mode, the second light-emitting mode, and the third light-emitting mode) can also be implemented with less hardware driver resources and power consumption, achieving functional diversity.

[0118] Optionally, see Figure 5 As shown, the second drive module 4 includes: a second pull-down unit 41;

[0119] The driving circuit also includes: a switching module 9, wherein the third current output terminal Out3 is connected to the second current output terminal Out2 and the second light-emitting module 5 respectively through the switching module 9;

[0120] When the second current output terminal Out2 outputs current, the second pull-down unit 41 is connected to the third current output terminal Out3. The switching module 9 disconnects the third current output terminal Out3 from the second current output terminal Out2 and the second light-emitting module 5. The second light-emitting module 5 operates in the second light-emitting mode.

[0121] When the third current output terminal Out3 outputs current, the second pull-down unit 41 is disconnected from the third current output terminal Out3, and the switching module 9 makes the third current output terminal Out3 connected to the second light-emitting module 5, and the second light-emitting module 5 operates in the third light-emitting mode.

[0122] For example, the second pull-down unit 41 can be switched between a first state and a second state. The first state is when the second pull-down unit 41 is connected to the third current output terminal Out3, and the second state is when the second pull-down unit 41 is disconnected from the third current output terminal Out3. For example, when the second drive module 4 is turned on, or when the third current output terminal Out3 outputs current, the second pull-down unit 41 is in the second state by default; when the second drive module 4 is turned off, or when the third current output terminal Out3 stops outputting current, the second pull-down unit 41 is in the first state by default to prevent current from flowing back from the third current output terminal Out3, thus providing isolation protection.

[0123] For example, the switching module 9 can be switched between a third state and a second state. The third state is a state in which the third current output terminal Out3 is disconnected from the second current output terminal Out2 and the second light-emitting module 5. The fourth state is a state in which the third current output terminal Out3 is connected to the second light-emitting module 5.

[0124] In this embodiment, when a second pull-down unit 41 is provided at the third current output terminal Out3 of the second driving module 4, since the second pull-down unit 41 and the third current output terminal Out3 are connected when the second driving module 4 is off, a switching module 9 is provided to prevent the current output from the second current output terminal Out2 of the first driving module 1 from being directly introduced to the reference ground through the second pull-down unit 41. When the second current output terminal Out2 outputs current and the second driving module 4 is off, it is in the third state, that is, the third current output terminal Out3 is disconnected from both the second current output terminal Out2 and the second light-emitting module 5 through the switching module 9. Therefore, the current output from the second current output terminal Out2 will not flow into the second pull-down unit 41, but will be directly input to the second light-emitting module 5, thereby ensuring that the second light-emitting module 5 can work normally in the second light-emitting mode. At the same time, when the second current output terminal Out2 stops outputting current and the second driving module 4 is on, the switching module 9 is in the fourth state, that is, the third current output terminal Out3 is connected to the second light-emitting module 5 through the switching module 9, and the second light-emitting module 5 works in the third light-emitting mode.

[0125] Optionally, the second pull-down unit 41 includes: a third resistor R3 and a second switch ( Figure 5 (not shown in the diagram), the first end of the third resistor R3 is connected to the third current output terminal Out3 via the second switch, and the second end of the third resistor R3 is connected to the reference ground.

[0126] Specifically, when the second drive module 4 is turned on, or when the third current output terminal Out3 outputs current, the second switch is turned off, that is, the third resistor R3 is disconnected from the third current output terminal Out3; when the second drive module 4 is turned off, or when the third current output terminal Out3 stops outputting current, the second switch is turned on, that is, the third current output terminal Out3 is connected to the reference through the third resistor R3, so as to prevent current from flowing back from the third current output terminal Out3 and play a role in isolation protection.

[0127] Optionally, the switching module 9 includes: a second capacitor C2 and a second switching unit Q2;

[0128] The second switching unit Q2 includes: a first terminal, a second terminal, and a control terminal; the first terminal is connected to the first terminal and the third current output terminal Out3 of the second capacitor C2 respectively, the second terminal is connected to the second light-emitting module 5 and the second current output terminal Out2 respectively, and the control terminal is connected to the second terminal of the second capacitor C2 and the second power supply M2 respectively.

[0129] Specifically, when the second current output terminal Out2 outputs current, the second power supply M2 stops supplying power to the control terminal, and the second switching unit Q2 is in a state of being disconnected between the first terminal and the second terminal; when the first current output terminal Out1 outputs current, or the third current output terminal Out3 outputs current, the second power supply M2 supplies power to the control terminal, and the second switching unit Q2 is in a state of being connected between the first terminal and the second terminal.

[0130] For example, the second power supply M2 can be the driving power supply for the camera module, or it can be an independently set power supply, etc., and the embodiments of this application are not limited thereto. Taking the second power supply M2 as the driving power supply for the camera module as an example, the application scenario of the third light-emitting mode is only activated when the camera module is working, and the application scenario of the second light-emitting mode is only activated when the camera module is not working. Therefore, when the camera module is working, the second power supply M2 will be powered on, that is, the second power supply M2 will only supply power in the third light-emitting mode. The second switching unit Q2 is in a state of conduction between the first terminal and the second terminal, so the third current output terminal Out3 is connected to the second light-emitting module 5 through the switching module 9, and the second light-emitting module 5 works in the third light-emitting mode. When the second power supply M2 does not supply power in the second light-emitting mode, that is, the second switching unit Q2 is in a state of disconnection between the first terminal and the second terminal, so the third current output terminal Out3 is disconnected from the second current output terminal Out2 and the second light-emitting module 5. Then the current output by the second current output terminal Out2 will not flow into the second pull-down unit 41, but will be directly input to the second light-emitting module 5, so that the second light-emitting module 5 works normally in the second light-emitting mode. By reusing the driving power supply of the camera module, the cost of components can be reduced.

[0131] In this embodiment, when the second driving module 4 is off and the third current output terminal Out3 is connected to the second pull-down unit 41, a second switch unit Q2 is connected in series in the output path of the third current output terminal Out3 of the second driving module 4. When not taking pictures (i.e., the camera module is not working), since the second power supply M2 does not supply power, the camera module is in the off state at this time, and the current output by the second current output terminal Out2 will not be diverted by the second pull-down unit 41, so the second light emission mode can be realized normally. When taking photos or recording videos (i.e., when the camera module is working), the second power supply M2 is powered on, charging the second capacitor C2. The second capacitor C2 then has the voltage of the second power supply M2. If the third light-emitting mode needs to be activated, the second drive module 2 can control the second pull-down unit 41 to be in the second state, that is, the second pull-down unit 41 is disconnected from the third current output terminal Out3. The second current output terminal Out2 outputs current, and the second capacitor C2 always maintains the voltage of the second power supply M2. Therefore, the second switch unit Q2 can be turned on normally, thereby realizing the conduction between the third current output terminal Out3 and the second light-emitting module 5, and the second light-emitting module 5 works in the third light-emitting mode.

[0132] Optionally, the switching module 9 further includes a third diode D3, the anode of which is connected to the second power supply M2, and the cathode of which is connected to the control terminal and the second terminal of the second capacitor C2 to prevent current from flowing back into the second power supply M2. Thus, due to the presence of the third diode D3, the high voltage at the control terminal of the second switching unit Q2 will not flow back into the second power supply M2, thereby achieving the normal second light-emitting mode and avoiding interference between the second and third light-emitting modes.

[0133] In this embodiment, a second switching unit Q2 is connected in series on the output path of the third current output terminal Out3 of the second driving module 4, and the switching state of the second switching unit Q2 is controlled by the second power supply M2 and the second capacitor C2. In the second light-emitting mode, the first driving module 1 can completely disconnect from the second driving module 4, and the second switching unit Q2 can be automatically turned on in the third light-emitting mode. This ensures the second light-emitting mode and avoids the influence between the second light-emitting mode and the third light-emitting mode.

[0134] This application provides an electronic device including the driving circuit described above.

[0135] Optionally, electronic devices include, but are not limited to: mobile phones, wearable devices, computers, tablets, cameras, etc., or other photographic (or video) devices with light-emitting functions, or other electronic devices, etc., and the embodiments of this application are not limited thereto.

[0136] It should be noted that the electronic device in the embodiments of this application can realize the various functions of the above-mentioned driving circuit and achieve the same technical effect. To avoid repetition, it will not be described again here.

[0137] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0138] Although preferred embodiments of the present application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments of the present application.

[0139] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes the element.

[0140] The above are preferred embodiments of this application. It should be noted that those skilled in the art can make several improvements and modifications without departing from the principles of this application, and these improvements and modifications are also within the protection scope of this application.

Claims

1. A drive circuit characterized by comprising: include: The first driving module, the timeout protection module, and the first light-emitting module; The first current output terminal of the first driving module is connected to the first light-emitting module, and the enable terminal of the first driving module is connected to the timeout protection module. If the voltage value output by the timeout protection module to the enable terminal is less than the first voltage threshold, the first driving module stops outputting current to the first light-emitting module.

2. The drive circuit according to claim 1, characterized by Also includes: A clock module, which is connected to the first drive module; The timeout protection module includes: a first pull-down unit, the output terminal of the first pull-down unit being connected to the enable terminal; When the first driving module detects that the current value output by the first current output terminal is greater than the first current threshold, it outputs a first instruction to the clock module, which is used to trigger the clock module to start timing. When the timing duration of the clock module exceeds a first duration threshold, the clock module sends a second instruction to the first drive module. The second instruction is used to cause the first drive module to trigger the first pull-down unit to input a voltage value at the enable terminal that is less than the first voltage threshold.

3. The drive circuit according to claim 1, characterized by Also includes: The processor, the timeout protection module includes: a delay circuit; The processor is connected to the enable terminal via the delay circuit; When the processor outputs a first enable voltage to the delay circuit, the voltage value output by the delay circuit to the enable terminal is greater than a second voltage threshold, and the first driving module outputs current to the first light-emitting module; after a first duration threshold, the voltage value output by the delay circuit to the enable terminal is less than the first voltage threshold.

4. The drive circuit according to claim 3, characterized in that, The delay circuit includes: a first capacitor and a first resistor; The first terminal of the first capacitor is connected to the processor, the second terminal of the first capacitor is connected to the first terminal of the first resistor, the first terminal of the first resistor is also connected to the enable terminal, and the second terminal of the first resistor is connected to the reference ground.

5. The drive circuit according to claim 4, characterized in that, The timeout protection module also includes: a clamping element; The first end of the clamping element is connected to the first end of the first resistor, and the second end of the clamping element is connected to the reference ground.

6. The drive circuit according to claim 4, characterized by The timeout protection module further includes: a first switching unit; The first switching unit includes a first terminal, a second terminal, and a control terminal; the first terminal is connected to the second terminal of the first capacitor, the second terminal is connected to a reference ground, and the control terminal is connected to the processor.

7. The drive circuit of claim 1, wherein The timeout protection module includes: a temperature control circuit; When the temperature of the first light-emitting module is greater than the first temperature threshold, the voltage value output by the temperature control circuit to the enable terminal is less than the first voltage threshold.

8. The drive circuit according to claim 7, characterized in that, The temperature control circuit includes: a second resistor and a thermistor; The first end of the second resistor is connected to the first power supply, the second end of the second resistor is connected to the first end of the thermistor, the first end of the thermistor is also connected to the enable terminal, and the second end of the thermistor is connected to the reference ground. The temperature-sensitive resistor is positioned close to the first light-emitting module, and its resistance decreases as the temperature increases.

9. The drive circuit according to any one of claims 1 to 8, characterized by Also includes: Second light-emitting module; The second current output terminal of the first driving module is connected to the second light-emitting module; When the first current output terminal outputs current to the first light-emitting module, the first light-emitting module operates in the first light-emitting mode; When the second current output terminal outputs current to the second light-emitting module, the second light-emitting module operates in the second light-emitting mode.

10. The drive circuit according to claim 9, characterized in that, Also includes: The second drive module and the first current protection module; The third current output terminal of the second driving module is connected to the second light-emitting module; The second current output terminal is connected to the second light-emitting module and the third current output terminal respectively through the first current protection module; When the third current output terminal outputs current to the second light-emitting module, the second light-emitting module operates in the third light-emitting mode.

11. The drive circuit according to claim 10, characterized in that, The second driving module includes: a second pull-down unit; The driving circuit further includes a switching module, wherein the third current output terminal is connected to the second current output terminal and the second light-emitting module respectively through the switching module; When the second current output terminal outputs current, the second pull-down unit is connected to the third current output terminal, and the switching module disconnects the third current output terminal from both the second current output terminal and the second light-emitting module. The second light-emitting module operates in the second light-emitting mode. When the third current output terminal outputs current, the second pull-down unit is disconnected from the third current output terminal, and the switching module makes the third current output terminal connected to the second light-emitting module, and the second light-emitting module operates in the third light-emitting mode.

12. The drive circuit of claim 11, wherein, The switching module includes: a second capacitor and a second switching unit; The second switching unit includes: a first terminal, a second terminal, and a control terminal; the first terminal is connected to the first terminal of the second capacitor and the third current output terminal, the second terminal is connected to the second light-emitting module and the second current output terminal, and the control terminal is connected to the second terminal of the second capacitor and the second power supply. Specifically, when current is output from the second current output terminal, the second power supply stops supplying power to the control terminal, and the second switching unit is in a disconnected state between the first terminal and the second terminal; when current is output from the first current output terminal or the third current output terminal, the second power supply supplies power to the control terminal, and the second switching unit is in a conducting state between the first terminal and the second terminal.

13. The drive circuit of claim 1, wherein, Also includes: processor; The processor is connected to the first driver module; The processor determines a first current value based on the first light intensity and outputs a third instruction to the first driving module. The third instruction is used to instruct the first current output terminal of the first driving module to output the first current value to the first light-emitting module.

14. An electronic device, comprising: Includes the drive circuit as described in any one of claims 1 to 13.

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