Camera motor driving circuit, driving chip, camera module and electronic device

Abstract

The application provides a camera motor driving circuit, a driving chip, a camera module and an electronic device. The camera motor driving circuit comprises: a motor driving module, which is used for outputting a driving signal to drive a camera motor; a position detection module, which is used for detecting a measured position of the camera motor; and a control module, which is used for outputting a control signal according to received motor stroke control data and an actual position of the camera motor, and the control signal is used for controlling the motor driving module to output the driving signal. The duty cycle of each pulse in the driving signal is equal to 50%, and the actual position of the camera motor is determined based on the pulse amplitude of the driving signal and the measured position of the camera motor. The application can eliminate the interference of the motor coil magnetic field on the position detection of the camera motor, and avoid the phenomenon that the actual position of the camera motor is deviated from the measured position, so as to cause the error of the movement control of the camera motor.

Description

Technical Field

[0001] This application relates to the field of camera technology, specifically to a camera motor drive circuit, a drive chip, a camera module, and an electronic device. Background Technology

[0002] Currently, camera modules typically need to have optical autofocus and / or optical image stabilization. Optical autofocus refers to the movement of optical lenses (or camera lenses) along the optical axis of the optical system to allow the camera to adjust focus and obtain a clear image. Optical image stabilization refers to the compensation process that uses the movement of optical lenses (or camera lenses) perpendicular to the optical axis to compensate for the displacement caused by equipment shake during recording, thereby avoiding image blurring due to equipment shake.

[0003] In related technologies, to ensure the control accuracy of camera motors, a feedback control method based on position detection and movement control is typically used. However, current camera motor position detection is affected by the drive signal, leading to control errors and preventing the motor from accurately moving to the designated position. Summary of the Invention

[0004] This application provides a camera motor drive circuit, a drive chip, a camera module, and an electronic device, aiming to solve the above-mentioned technical problems.

[0005] In a first aspect, this application provides a camera motor drive circuit, comprising:

[0006] Motor drive module, the motor drive module is used to output drive signals to drive the camera motor;

[0007] Position detection module, used to detect the measurement position of the camera motor;

[0008] The control module is used to output control signals based on the received motor stroke control data and the actual position of the camera motor. The control signals are used to control the motor drive module to output drive signals.

[0009] In this system, the duty cycle of each pulse in the drive signal is 50%, and the actual position of the camera motor is determined based on the pulse amplitude of the drive signal and the measured position of the camera motor.

[0010] In some embodiments, the actual position of the camera motor is positively correlated with the measured position of the camera motor, and the actual position of the camera motor is negatively correlated with the pulse amplitude of the drive signal.

[0011] In some embodiments, the actual position of the camera motor is determined once per cycle of the drive signal; or

[0012] The actual position of the camera motor is determined once every N cycles of the drive signal, where N is an integer greater than 1.

[0013] In some embodiments, the position detection module is used to detect the magnetic field of the camera motor to determine the measurement position of the camera motor;

[0014] The measurement position of the camera motor is determined based on the average magnitude and / or integral result of the magnetic field detected by the position detection module during at least one cycle of the drive signal.

[0015] In some embodiments, the camera motor includes a motor coil and a magnet;

[0016] The motor coil receives the drive signal output by the motor drive module and generates a magnetic field, and the magnet moves under the action of the magnetic field of the motor coil.

[0017] The position detection module is used to detect the magnetic field of the magnet and the motor coil to determine the measurement position of the camera motor.

[0018] In some embodiments, the position detection module includes a magnetic field detection unit and a position determination unit;

[0019] The magnetic field detection unit is used to detect the magnetic field strength of the camera motor;

[0020] The position determination unit is used to determine the measurement position of the camera motor based on the magnetic field strength of the camera motor, and to determine the actual position of the camera motor based on the pulse amplitude of the drive signal and the measurement position of the camera motor.

[0021] In some embodiments, the pulse amplitude of each pulse of the drive signal is controlled by a control signal.

[0022] In some embodiments, the control signal includes a drive control signal and a current control signal;

[0023] The drive control signal is used to control the pulse of the drive signal output by the motor drive module, and the current control signal is used to control the pulse amplitude of the drive signal output by the motor drive module.

[0024] In some embodiments, the motor drive module includes an H-bridge drive unit and a current control unit;

[0025] The H-bridge drive unit is used to output drive signals, and the current control unit is used to control the current of the H-bridge drive unit.

[0026] Among them, the drive control signal is used to control the H-bridge drive unit, and the current control signal is used to control the current control unit.

[0027] Secondly, this application provides a camera motor driver chip, including the camera motor driver circuit as described in the second aspect.

[0028] Thirdly, this application provides a camera module, including a camera motor driver chip as described in the third aspect.

[0029] Fourthly, this application provides an electronic device including a camera module as described in the fourth aspect.

[0030] In this embodiment, since the duty cycle of each pulse in the drive signal is 50%, the integral result or average magnitude of the magnetic field of the motor coil in each cycle of the drive signal has a first-order linear relationship with the pulse amplitude of the drive signal. This helps to eliminate the interference of the magnetic field of the motor coil on the position detection of the camera motor, and ultimately allows the actual position of the camera motor to be determined based on the pulse amplitude of the drive signal and the measured position of the camera motor, thus avoiding the phenomenon that the actual position of the camera motor deviates from the measured position, which would cause errors in the movement control of the camera motor. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 This diagram illustrates a camera lens movement control circuit in the related art.

[0033] Figure 2 This diagram illustrates a motor drive module in the related art;

[0034] Figure 3 This diagram illustrates a relationship between drive current and motor displacement in related technologies.

[0035] Figure 4 This diagram illustrates a method for detecting the magnetic field of a motor coil and the motor position in related technologies.

[0036] Figure 5 A schematic diagram of a camera motor drive circuit in an embodiment of this application is shown;

[0037] Figure 6 A schematic diagram of a camera motor in an embodiment of this application is shown;

[0038] Figure 7 This paper shows a schematic diagram of the driving signal and the magnetic field of the motor coil in an embodiment of this application;

[0039] Figure 8 Another schematic diagram of the camera motor drive circuit in an embodiment of this application is shown;

[0040] Figure 9 Another schematic diagram of the camera motor drive circuit in an embodiment of this application is shown;

[0041] Figure 10 A schematic diagram of a drive signal in an embodiment of this application is shown;

[0042] Figure 11 Another schematic diagram of the camera motor drive circuit according to an embodiment of this application is shown;

[0043] Figure 12 A schematic diagram of a motor drive module in an embodiment of this application is shown;

[0044] Figure 13 Another schematic diagram of the motor drive module in an embodiment of this application is shown.

[0045] Among them, there are 100 camera motor drive circuits, 200 camera motors, 210 motor coils, 220 magnets, and 300 camera lenses;

[0046] 10 Motor drive module, 11 H-bridge drive unit, 12 Current control unit, 20 Position detection module, 21 Magnetic field detection unit, 22 Position determination unit, 30 Control module;

[0047] Control signal NC, drive signal DRV, drive control signal DPC, current control signal IPC, first transistor M1, second transistor M2, third transistor M3, fourth transistor M4, power supply terminal VDD, ground terminal GND. Detailed Implementation

[0048] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0049] In the description of this invention, the term "exemplary" is used to mean "serving as an example, illustration, or description." Any embodiment described as "exemplary" in this application is not necessarily to be construed as being more preferred or advantageous than other embodiments. The following description is provided to enable any person skilled in the art to make and use the invention. Details are set forth in the following description for purposes of explanation. It should be understood that those skilled in the art will recognize that the invention can be made without using these specific details. In other instances, well-known structures and processes will not be described in detail to avoid obscuring the description of the invention with unnecessary detail. Therefore, the invention is not intended to be limited to the embodiments shown, but is consistent with the broadest scope of the principles and features disclosed in this application.

[0050] Currently, to achieve optical focusing and / or optical image stabilization, camera modules typically require a camera motor to drive the camera lens for movement. (See [reference needed]) Figure 1 , Figure 1 A schematic diagram of a camera lens movement control circuit in the related art is shown, wherein the camera lens movement control circuit includes a motor drive circuit, a camera motor, and a camera lens.

[0051] Specifically, the motor drive circuit includes a digital control module, a motor drive module, and a position detection module. The position detection module is used to detect the position of the camera motor (camera lens). The digital control module combines the position of the camera motor with the received control commands or data to output a control signal to the motor drive module, so that the motor drive module outputs a drive current to drive the camera motor and move the camera lens.

[0052] The camera motor includes a motor coil and a magnet. The magnet and camera lens are fixed to the mover bracket of the camera motor, while the motor coil is fixed to the stator bracket. The mover bracket can move relative to the stator bracket. After the motor drive module inputs drive current to the motor coil, the motor coil on the stator bracket generates a magnetic field. The magnetic field of the motor coil on the stator bracket interacts with the magnetic field of the magnet on the mover bracket to generate a magnetic thrust, thereby pushing the mover bracket to move the magnet and camera lens relative to the stator bracket.

[0053] More specifically, see Figure 2 , Figure 2 A schematic diagram of a motor drive module in the related art is shown. The motor drive module includes an H-bridge circuit composed of a first transistor M1, a second transistor M2, a third transistor M3, and a fourth transistor M4. The H-bridge circuit controls the connection of the two ends of the motor coil to the power supply terminal VDD or the ground terminal GND. Therefore, the H-bridge circuit can control the direction of the current flowing into the motor coil, thereby controlling the movement of the mover bracket relative to the stator bracket in the positive or negative direction.

[0054] For example, see Figure 3 , Figure 3 The diagram illustrates a driving current and motor displacement in the related art. When the first transistor M1 and the fourth transistor M4 are turned on, and the second transistor M2 and the third transistor M3 are turned off, a positive current is supplied to the motor coil, causing the mover support to move in the positive direction relative to the stator support. When the first transistor M1 and the fourth transistor M4 are turned off, and the second transistor M2 and the third transistor M3 are turned on, a reverse current is supplied to the motor coil, causing the mover support to move in the opposite direction relative to the stator support.

[0055] However, see Figure 1 Currently, position detection modules typically determine the camera lens's position by detecting the magnetic field of a magnet. However, during the driving of the motor coil, the motor coil also generates a magnetic field. Since the magnetic field of the motor coil is a changing quantity, it will interfere with the position detection of the camera lens. For example, see... Figure 4 , Figure 4 The diagram illustrates a method for detecting the magnetic field of a motor coil and its position in a related technology. In this method, the change in the magnetic field of the motor coil is similar to the driving current flowing through the motor coil. Due to interference from the magnetic field of the motor coil, the actual displacement of the motor deviates from the detected position, which increases the error in the position detection of the camera lens.

[0056] Based on the above technical problems, this application provides a camera motor drive circuit, a drive chip, a camera module, and an electronic device, which will be described in detail below.

[0057] First, refer to Figure 5 , Figure 5 A schematic diagram of a camera motor 200 drive circuit 100 in an embodiment of this application is shown, wherein the camera motor 200 drive circuit 100 includes a motor drive module 10, a position detection module 20 and a control module 30.

[0058] Specifically, the motor drive module 10 outputs a drive signal DRV to drive the camera motor 200. In some embodiments of this application, the motor drive module 10 can be voltage-driven, meaning the drive signal DRV can be a voltage signal, and the motor drive module 10 can control the voltage input to the camera motor 200 to control the movement of the camera lens 300. In some embodiments of this application, the motor drive module 10 can be current-driven, meaning the drive signal DRV can be a current signal, and the motor drive module 10 can control the current input to the camera motor 200 to control the movement of the camera lens 300.

[0059] Generally, the motor drive module 10 may include an H-bridge circuit. The H-bridge circuit controls the current direction of the camera motor 200 by controlling the on / off state of four switching elements (such as transistors, MOSFETs, etc.), thereby controlling the camera motor 200 to perform focus movement or image stabilization movement.

[0060] It is understood that the implementation of the motor drive module 10 is not limited to this. The motor drive module 10 may also use other drive circuits. For example, the motor drive module 10 may also include a half-bridge circuit to drive the camera motor 200 to work.

[0061] It should be noted that, in this embodiment, the camera motor 200 can be a focusing camera motor 200, an image stabilization camera motor 200, or a focusing-and-image-stabilization camera motor 200. Specifically, the focusing camera motor 200 refers to a camera motor 200 that controls the optical lens for optical focusing, the image stabilization camera motor 200 refers to a camera motor 200 that controls the optical lens for optical image stabilization, and the focusing-and-image-stabilization camera motor 200 is a camera motor 200 that controls both optical focusing and image stabilization of the optical lens. More specifically, optical focusing refers to the focusing process by moving the optical lens (or camera lens 300) along the optical axis of the optical system to facilitate focusing adjustment and obtain a clear image. Optical image stabilization refers to the compensation process by moving the optical lens (or camera lens 300) in a direction perpendicular to the optical axis to compensate for the displacement caused by equipment shake during recording, thereby avoiding image blurring due to equipment shake.

[0062] It should be noted that the motor drive module 10 of this application can control the camera motor 200 to move along one or more directions. For example, taking the camera motor 200 as a focusing camera motor 200, the motor drive module 10 can include an H-bridge circuit, through which the camera motor 200 can be controlled to move along the focusing direction, thereby realizing the focusing process of the optical lens; as another example, taking the camera motor 200 as an image-stabilized camera motor 200, the motor drive module 10 can include two H-bridge circuits. One H-bridge circuit of the motor drive module 10 can control the camera motor 200 to move along one image-stabilized direction (e.g., the X-axis direction perpendicular to the optical axis), and the other H-bridge circuit of the motor drive module 10 can control the camera motor 200 to move along another image-stabilized direction (e.g., the Y-axis direction perpendicular to the optical axis). For example, if the camera motor 200 is a stabilized camera motor 200, the motor drive module 10 may also include only one H-bridge circuit. One H-bridge circuit can control the camera motor 200 to move along a stabilized direction (e.g., the X-axis perpendicular to the optical axis).

[0063] As an exemplary embodiment of the camera motor 200, see [reference]. Figure 6 , Figure 6 A schematic diagram of a camera motor 200 in an embodiment of this application is shown. The camera motor 200 includes a motor coil 210 and a magnet 220. The motor coil 210 can be fixed on the stator support of the camera motor 200, and the magnet 220 can be fixed on the mover support of the camera motor 200. The mover support can move relative to the stator support. After the motor coil 210 receives the drive signal DRV output by the motor drive module 10 and generates a magnetic field, the magnet 220 moves under the action of the magnetic field of the motor coil 210, thereby causing the mover support that fixes the magnet 220 and the camera lens 300 to move relative to the stator support.

[0064] The position detection module 20 is used to detect the measured position of the camera motor 200, so as to determine the actual position of the camera motor 200 based on the measured position, enabling the control module 30 to realize a closed-loop feedback control process of position detection and position control of the camera motor 200. Generally, the position detection module 20 may include various sensors for measuring distance or position, such as potentiometer-type displacement sensors, inductive displacement sensors, capacitive displacement sensors, eddy current displacement sensors, or Hall effect displacement sensors.

[0065] It should be noted that the camera motor 200 typically includes a stator support and a mover support. The stator support is fixed relative to the main body of the electronic device, while the mover support is movable relative to the stator support (e.g., moving along the optical axis or the image stabilization direction). Optical lenses (or optical lenses) can be mounted on the mover support to achieve optical focusing or optical image stabilization functions through the movement of the mover support relative to the stator support. In the embodiments of this application, unless otherwise specified, the position (measured position or actual position) of the camera motor 200 refers to the position of the mover support of the camera motor 200 relative to the stator support.

[0066] In some embodiments of this application, the position detection module 20 can detect the magnetic field of the camera motor 200 to determine the measurement position of the camera motor 200. For example, in an embodiment where the camera motor 200 includes a motor coil 210 and a magnet 220, the position detection module 20 is used to detect the magnetic field of the magnet 220 and the magnetic field of the motor coil 210 to determine the measurement position of the camera motor 200. Since the magnet 220 moves with the mover bracket, the magnitude of the magnetic field of the magnet 220 is related to the measurement position of the camera motor 200. Thus, by detecting the magnetic field of the magnet 220 and the magnetic field superimposed on the motor coil 210, the measurement position of the camera motor 200 can be determined, so as to combine the measurement position of the camera motor 200 with the drive signal DRV output by the motor drive module 10 to determine the actual position of the camera motor 200.

[0067] It should be noted that, in the embodiments of this application, the measured position of the camera motor 200 refers to the position of the camera motor 200 determined by the motor measurement module under the interference generated by the drive signal DRV (for example, the interference magnetic field generated by the drive current of the motor coil 210). The measured position of the camera motor 200 is subject to interference error caused by the drive signal DRV. The actual position of the camera motor 200 refers to the position of the camera motor 200 determined by correcting the measured position of the camera motor 200 and eliminating the interference error caused by the drive signal DRV.

[0068] It is understood that the above example illustrates that the interference caused by the drive signal DRV is the interference magnetic field superimposed on the motor coil 210, with the camera motor 200 being a coil motor. However, in some possible embodiments, the camera motor 200 may also be a linear motor or a DC motor, and the interference generated by the drive signal DRV may also be interference to other types of sensors (such as potentiometer displacement sensors, inductive displacement sensors, capacitive displacement sensors, eddy current displacement sensors, or Hall effect displacement sensors).

[0069] The control module 30 outputs a control signal NC based on the received motor stroke control data and the actual position of the camera motor 200, so as to control the motor drive module 10 to output a drive signal DRV. In some embodiments of this application, the control module 30 may include a PID controller (Proportional-Integral-Derivative controller) to achieve feedback control of the camera motor 200. In some embodiments of this application, the control module 30 may also be a PI controller (Proportional-Integral controller) to achieve feedback control of the camera motor 200.

[0070] Those skilled in the art will understand that the implementation of the control module 30 is not limited thereto. For example, the control module 30 may also include a PI-D controller, a fuzzy controller, or a smooth controller.

[0071] In this embodiment, the duty cycle of each pulse in the drive signal DRV is 50%, and the actual position of the camera motor 200 is determined based on the pulse amplitude of the drive signal DRV and the measured position of the camera motor 200.

[0072] For example, taking the camera motor 200, which includes a motor coil 210 and a magnet 220, as an example, see [link to relevant documentation]. Figure 7 , Figure 7This diagram illustrates a scenario of the driving signal DRV and the magnetic field of the motor coil 210 in an embodiment of this application. The duration of each high-level pulse of the driving signal DRV is T / 2, and the duration of each low-level pulse is T / 2. In this case, during the positive and negative half-cycles of each period of the driving signal DRV, the magnetic field of the motor coil 210 exhibits the same trend but opposite directions, making the dynamic interference 1 during the positive half-cycle and the dynamic interference 2 during the negative half-cycle complementary. Furthermore, the stable interference of the motor coil's magnetic field is positively correlated with the pulse amplitude of the driving signal DRV. Therefore, by integrating over the entire cycle, the area of ​​dynamic interference 2 can fill the area of ​​dynamic interference 1, forming a gray area (i.e., the integrated result of the motor coil's magnetic field) that is proportional to the pulse amplitude of the driving signal. Taking the approximate upward and downward trend of the magnetic field of the motor coil 210 as a first-order curve as an example, it can be seen that the integrated result of the magnetic field of the motor coil 210 during each cycle of the driving signal DRV is:

[0073]

[0074] Where C1 and C2 are magnetic field coefficients (e.g., magnetic field coefficients related to permeability, dielectric constant, number of coil turns, etc.), I(t) is the magnitude of the driving signal DRV over time, I is the pulse amplitude of the driving signal DRV, and K is a coefficient.

[0075] As can be seen from the above exemplary formula, the integral result of the magnetic field of the motor coil 210 in each cycle of the drive signal DRV has a first-order linear relationship with the pulse amplitude of the drive signal DRV. After the magnetic field of the motor coil 210 interferes with the position detection of the camera motor 200, it can be seen that the following relationship is satisfied for the measured position of the camera motor 200 detected by the position detection module 20:

[0076] S1=S0+k0*I

[0077] Where S1 is the measured position of the camera motor 200, S0 is the actual position of the camera motor 200, and k0 is a coefficient.

[0078] Therefore, the actual position of the camera motor 200 can be calculated according to the following formula:

[0079] S0=S1-k0*I

[0080] It can be seen that the actual position of the camera motor 200 is positively correlated with the measured position of the camera motor 200, while the actual position of the camera motor 200 is negatively correlated with the pulse amplitude of the drive signal DRV. At the same time, the interference of the drive signal DRV on the position detection of the camera motor 200 can be eliminated after calculation according to the above formula, thus avoiding the phenomenon that the actual position of the camera motor 200 deviates from the measured position, which would cause errors in the movement control of the camera motor 200.

[0081] In this embodiment, since the duty cycle of each pulse in the drive signal DRV is 50%, the integral result or average magnitude of the magnetic field of the motor coil 210 in each cycle of the drive signal DRV has a first-order linear relationship with the pulse amplitude of the drive signal DRV. This helps to eliminate the interference of the magnetic field of the motor coil 210 on the position detection of the camera motor 200, and ultimately allows the actual position of the camera motor 200 to be determined based on the pulse amplitude of the drive signal DRV and the measured position of the camera motor 200, thus avoiding the phenomenon that the actual position of the camera motor 200 deviates from the measured position, which would cause errors in the movement control of the camera motor 200.

[0082] It should be noted that the above embodiments are illustrated by integrating the coil magnetic field once per cycle of the drive signal DRV. Therefore, the actual position of the camera motor 200 can be determined once per cycle of the drive signal DRV, but it is not limited to this. For example, the actual position of the camera motor 200 can be determined once every N cycles of the drive signal DRV, where N is an integer greater than 1. Those skilled in the art can set it according to actual needs (e.g., the position detection frequency requirement of the camera motor 200), and this application does not impose any specific limitations.

[0083] In some embodiments of this application, such as an embodiment where the position detection module 20 detects the magnetic field of the camera motor 200 to determine the measured position of the camera motor 200, the measured position of the camera motor 200 is determined based on the average magnitude and / or integral result of the magnetic field detected by the position detection module 20 during at least one cycle of the drive signal DRV.

[0084] For example, taking the camera motor 200, which includes a motor coil 210 and a magnet 220, as an example, the position detection module 20 detects the magnetic field strength of the motor coil 210 and the magnet 220 multiple times in each cycle of the drive signal DRV. Then, by calculating the multiple measured magnetic field strengths, the measurement position of the camera motor 200 can be determined. For example, the average value of the multiple measured magnetic field strengths can be calculated, and the measurement position of the camera motor 200 can be determined based on the average magnitude of the obtained magnetic field. Alternatively, the summation of the multiple measured magnetic field strengths can be performed, and the measurement position of the camera motor 200 can be determined based on the integral result of the obtained magnetic field.

[0085] In some embodiments of this application, see Figure 8 , Figure 8Another schematic diagram of the camera motor 200 drive circuit 100 in an embodiment of this application is shown, wherein the position detection module 20 includes a magnetic field detection unit 21 and a position determination unit 22; the magnetic field detection unit 21 is used to detect the magnetic field strength of the camera motor 200; the position determination unit 22 is used to determine the measurement position of the camera motor 200 based on the magnetic field strength of the camera motor 200, and to determine the actual position of the camera motor 200 based on the pulse amplitude of the drive signal DRV and the measurement position of the camera motor 200.

[0086] For example, the magnetic field detection unit 21 can measure the magnetic field strength of the motor coil 210 and the magnet 220 multiple times in each cycle of the drive signal DRV. The position determination module calculates the average magnitude and / or integral result of the magnetic field based on the multiple measured magnetic field strengths, and then calculates the measured position of the camera motor 200 based on the average magnitude and / or integral result of the magnetic field. It also combines the pulse amplitude of the drive signal DRV in the current cycle with the measured position of the camera motor 200 to calculate the actual position of the camera motor 200.

[0087] For example, the magnetic field detection unit 21 may include, but is not limited to, a Hall sensor, a magnetic flux sensor, or a magneto-optical sensor.

[0088] In some embodiments of this application, the pulse amplitude of each pulse of the drive signal DRV is controlled by the control signal NC. Therefore, by controlling the amplitude of each pulse, the voltage or current signal input to the camera motor 200 can be changed, thereby controlling the displacement of the camera motor 200 to reach the specified position.

[0089] It should be noted that, in the embodiments of this application, the pulse widths of multiple pulses within the cycle of each drive signal DRV are generally equal and constant. However, in some possible embodiments, the pulse widths of multiple pulses can also be controlled by the control signal NC to adjust the displacement of the camera motor 200 by adjusting the pulse width. This application does not impose specific limitations.

[0090] In some embodiments of this application, see Figure 9 , Figure 9 Another schematic diagram of the camera motor 200 drive circuit 100 in an embodiment of this application is shown, wherein the control signal NC includes a drive control signal DPC and a current control signal IPC; wherein the drive control signal DPC is used to control the output drive signal DRV pulse of the motor drive module 10, and the current control signal IPC is used to control the pulse amplitude of the output drive signal DRV of the motor drive module 10.

[0091] For example, see Figure 10 , Figure 10The diagram shows a schematic of a drive signal DRV in an embodiment of this application. For the drive signal DRV, there are two consecutive periodic pulses, one positive and one negative. The drive control signal DPC can control the rising and falling edges of the positive and negative pulses, while the current control signal IPC can control the pulse amplitude of the positive and negative pulses, so as to control the displacement of the camera motor 200 to reach the specified position.

[0092] In some embodiments of this application, see Figure 11 , Figure 11 A schematic diagram of a motor drive module 10 in an embodiment of this application is shown. The motor drive module 10 includes an H-bridge drive unit 11 and a current control unit 12. The H-bridge drive unit 11 is used to output a drive signal DRV, and the current control unit 12 is used to control the current magnitude of the H-bridge drive unit 11. The drive control signal DPC is used to control the H-bridge drive unit 11, and the current control signal IPC is used to control the current control unit 12. Therefore, the drive control signal DPC can control the H-bridge drive unit 11 to output a drive signal DRV with multiple pulses, and the current control signal IPC can control the pulse amplitude of the pulses in the drive signal DRV.

[0093] As an example, see Figure 12 , Figure 12 Another schematic diagram of the motor drive module 10 in this embodiment is shown. The H-bridge drive unit 11 includes an H-bridge circuit composed of a first transistor M1, a second transistor M2, a third transistor M3, and a fourth transistor M4. The H-bridge circuit controls the connection of the camera motor 200 to either the power supply terminal VDD or the ground terminal GND based on the drive control signal DPC. Therefore, the H-bridge drive unit 11 can output a drive signal DRV with multiple pulses per cycle to control the direction of the current flowing into the camera motor 200 and the direction in which the camera motor 200 drives the camera lens 300. Simultaneously, the current control unit 12 includes a controllable current source IS. The controllable current source IS can control the magnitude of the current flowing into the ground terminal GND through the first transistor M1 and the fourth transistor M4 (or the third transistor M3 and the second transistor M2) based on the current control signal IPC, thereby changing the pulse amplitude of the drive signal DRV output by the H-bridge drive unit 11.

[0094] It is understood that the implementation of the motor drive module 10 is not limited to this. For example, in some possible embodiments, the drive control signal DPC can also be used to control the direction of the drive signal DRV output by the motor drive module 20, and the current control signal IPC can also be used to control the pulse and pulse amplitude of the drive signal DRV output by the motor drive module 20. Figure 12For example, in the positive half-cycle, the drive control signal DPC controls the first transistor M1 and the fourth transistor M4 to remain on, and the current control signal IPC controls the controllable current source IS to output multiple pulse currents with different pulse amplitudes in the positive half-cycle; in the negative half-cycle, the drive control signal DPC controls the second transistor M2 and the third transistor M3 to remain on, and the current control signal IPC controls the controllable current source IS to output multiple pulse currents with different pulse amplitudes in the negative half-cycle. That is, in both the positive and negative half-cycles, the drive control signal DPC controls the current direction of the drive signal DRV output by the motor drive module 20, while the current control signal IPC controls the current pulses and pulse amplitudes of the drive signal DRV output by the motor drive module 20; for another example, see [reference needed]. Figure 13 , Figure 13 Another schematic diagram of the motor drive module 10 in this embodiment is shown. The controllable current source IS can also be connected to the power supply terminal VDD, and the pulse amplitude of the drive signal DRV can be changed by controlling the input current of the power supply terminal VDD.

[0095] It is worth noting that the above description of the camera motor 200 drive circuit 100 is intended to clearly illustrate the implementation and verification process of this application. Those skilled in the art can make equivalent modifications and designs under the guidance of this application. For example, this application embodiment uses the calculation of the actual position of the camera module by the position determination unit 22 of the position detection module 20 as an example for illustrative purposes. However, in some possible embodiments, the position detection module 20 may only include the magnetic field detection unit 21. The magnetic field detection unit 21 forwards the detected magnetic field strength data to the control module 30, and the control module 30 calculates the actual position of the camera module.

[0096] Furthermore, to better implement the camera motor 200 drive circuit 100 in the embodiments of this application, based on the camera motor 200 drive circuit 100, this application also provides a camera motor 200 drive chip, which includes the camera motor 200 drive circuit 100 as described in any of the above embodiments. Since the camera motor 200 drive chip in the embodiments of this application has all the beneficial effects of the camera motor 200 drive circuit 100 described above, it will not be repeated here.

[0097] Furthermore, to better implement the camera motor 200 driver chip in the embodiments of this application, based on the camera motor 200 driver chip, this application also provides a camera module, which includes the camera motor 200 driver chip as described in any of the above embodiments. Since the camera module in the embodiments of this application has all the beneficial effects of the camera motor 200 driver circuit 100 described in the above embodiments, it will not be repeated here.

[0098] Furthermore, this application also provides an electronic device, which includes a device body and a camera module as described above disposed within the device body. The electronic device may be, but is not limited to, smart wearable devices, mobile terminals, smart home devices, etc. Smart wearable devices include, but are not limited to, smartwatches, smart bracelets, smart glasses, neck massagers, etc. Mobile terminals include, but are not limited to, smartphones, laptops, tablets, in-vehicle computers, etc. Smart home devices include, but are not limited to, smart robot vacuums, smart lights, smart floor scrubbers, window cleaning robots, etc.

[0099] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the detailed descriptions of other embodiments above, which will not be repeated here.

[0100] The basic concepts have been described above. Obviously, for those skilled in the art, the detailed disclosure above is merely illustrative and does not constitute a limitation of this application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements, and corrections to this application. Such modifications, improvements, and corrections are suggested in this application, and therefore remain within the spirit and scope of the exemplary embodiments of this application.

[0101] Furthermore, this application uses specific terms to describe embodiments of the application. For example, "an embodiment," "one embodiment," and / or "some embodiments" refer to a particular feature, structure, or characteristic associated with at least one embodiment of the application. Therefore, it should be emphasized and noted that "an embodiment," "one embodiment," or "an alternative embodiment" mentioned twice or more in different locations in this specification do not necessarily refer to the same embodiment. In addition, certain features, structures, or characteristics in one or more embodiments of the application can be appropriately combined.

[0102] Similarly, it should be noted that, in order to simplify the description of the present application and thus aid in the understanding of one or more embodiments of the invention, the foregoing description of the embodiments of the present application sometimes combines multiple features into a single embodiment, drawing, or description thereof. However, this disclosure method does not imply that the subject matter of the application requires more features than those mentioned in the claims. In fact, the embodiments contain fewer features than all the features of the single embodiments disclosed above.

[0103] The foregoing has provided a detailed description of the camera motor 200 drive circuit 100, drive chip, camera module, and electronic device provided in the embodiments of this application. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A camera motor drive circuit, characterized in that, include: A motor drive module, wherein the motor drive module is used to output drive signals to drive the camera motor; A position detection module, which is used to detect the measurement position of the camera motor; The control module is used to output a control signal based on the received motor stroke control data and the actual position of the camera motor. The control signal is used to control the motor drive module to output the drive signal. Wherein, the duty cycle of each pulse in the drive signal is equal to 50%, and the actual position of the camera motor is determined based on the pulse amplitude of the drive signal and the measured position of the camera motor; The position detection module is used to detect the magnetic field of the camera motor to determine the measurement position of the camera motor; The measurement position of the camera motor is determined based on the average magnitude and / or integral result of the magnetic field detected by the position detection module during at least one cycle of the drive signal.

2. The camera motor drive circuit as described in claim 1, characterized in that, The actual position of the camera motor is positively correlated with the measured position of the camera motor, and the actual position of the camera motor is negatively correlated with the pulse amplitude of the drive signal.

3. The camera motor drive circuit as described in claim 1, characterized in that, The actual position of the camera motor is determined once per cycle of the drive signal; or The actual position of the camera motor is determined once every N cycles of the drive signal, where N is an integer greater than 1.

4. The camera motor drive circuit as described in claim 1, characterized in that, The camera motor includes a motor coil and a magnet; The motor coil receives the drive signal output by the motor drive module and generates a magnetic field, and the magnet moves under the action of the magnetic field of the motor coil. The position detection module is used to detect the magnetic field of the magnet and the motor coil to determine the measurement position of the camera motor.

5. The camera motor drive circuit as described in claim 1, characterized in that, The position detection module includes a magnetic field detection unit and a position determination unit; The magnetic field detection unit is used to detect the magnetic field strength of the camera motor; The position determination unit is used to determine the measurement position of the camera motor based on the magnetic field strength of the camera motor, and to determine the actual position of the camera motor based on the pulse amplitude of the drive signal and the measurement position of the camera motor.

6. The camera motor drive circuit as described in claim 1, characterized in that, The amplitude of each pulse of the driving signal is controlled by the control signal.

7. The camera motor drive circuit as described in claim 6, characterized in that, The control signals include drive control signals and current control signals; The drive control signal is used to control the motor drive module to output the drive signal pulse, and the current control signal is used to control the pulse amplitude of the drive signal output by the motor drive module. or The drive control signal is used to control the direction of the drive signal output by the motor drive module, and the current control signal is used to control the pulse and pulse amplitude of the drive signal output by the motor drive module.

8. The camera motor drive circuit as described in claim 7, characterized in that, The motor drive module includes an H-bridge drive unit and a current control unit; The H-bridge drive unit is used to output the drive signal, and the current control unit is used to control the current magnitude of the H-bridge drive unit; The drive control signal is used to control the H-bridge drive unit, and the current control signal is used to control the current control unit.

9. A camera motor driver chip, characterized in that, Includes the camera motor drive circuit as described in any one of claims 1 to 8.

10. A camera module, characterized in that, Includes the camera motor driver chip as described in claim 9.

11. An electronic device, characterized in that, Includes the camera module as described in claim 10.

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