Capacitance module detection circuit, chip, optical lens movement detection device, focusing motor, camera module and electronic equipment

Abstract

The invention provides a capacitor module detection circuit, a chip, an optical lens movement detection device, a focusing motor, a camera module and electronic equipment, and the capacitor module detection circuit comprises a voltage control module which is used for controlling the voltage of a second polar plate of a first capacitor and the voltage of a second polar plate of a second capacitor; and the measuring module is used for outputting a first digital signal related to a first capacitance value and a second digital signal related to a second capacitance value according to the quantity of electric charges released by the second polar plate of the third capacitor in the process that the voltage control module changes the voltage of the second polar plate of the first capacitor and the voltage of the second polar plate of the second capacitor. The capacitor module detection circuit is only connected with the second polar plate of the first capacitor, the second polar plate of the second capacitor and the second polar plate of the third capacitor, and does not need to be connected with the first polar plate and the second polar plate of the same capacitor, so that the manufacturing difficulty of the optical lens movement detection device is reduced.

Description

Technical Field

[0001] This application relates to the field of integrated circuit technology, specifically to a capacitor module detection circuit, a chip, an optical lens movement detection device, a focusing motor, a camera module, and electronic equipment. Background Technology

[0002] Currently, camera modules typically require both optical autofocus and optical image stabilization (OIS). Optical autofocus refers to the movement of optical lenses (or optical mirrors) along the optical axis of the optical system to allow the camera to adjust focus and obtain a clear image. Optical image stabilization compensates for the displacement caused by camera shake during recording by moving optical lenses (or optical mirrors) perpendicular to the optical axis, thus preventing image blurring due to camera shake. Therefore, camera modules need to have optical lens movement detection capabilities to detect the movement of optical lenses during focusing and OIS, achieving a closed-loop control process of optical lens movement control and detection.

[0003] In related technologies, to reduce the cost of optical lens movement detection schemes, a capacitor structure is used to detect the movement of the optical lens. In this scheme, one plate of the capacitor is fixed, while the other plate moves with the optical lens. The change in the distance / area between the two plates is calculated by measuring the capacitance value, thereby determining the movement position of the optical lens. However, measuring the capacitance value typically requires the detection circuit to be electrically connected to both plates of the capacitor separately; that is, the detection circuit needs to connect to both a fixed plate and a moving plate. This is extremely difficult for miniaturized camera modules in electronic devices. Summary of the Invention

[0004] This application provides a capacitor module detection circuit, a chip, an optical lens movement detection device, a focusing motor, a camera module, and an electronic device to solve the above-mentioned technical problems.

[0005] In a first aspect, this application provides a capacitor module detection circuit. The capacitor module includes a first capacitor, a second capacitor, and a third capacitor. The first plates of the first capacitor, the second capacitor, and the third capacitor are electrically connected to each other. The capacitor module detection circuit includes:

[0006] The voltage control module is used to control the voltage of the second plate of the first capacitor and the second plate of the second capacitor.

[0007] The measurement module is used to output a first digital signal related to the value of the first capacitor based on the amount of charge released by the second plate of the third capacitor during the process of the voltage control module changing the voltage of the second plate of the first capacitor and the second plate of the second capacitor, and to output a second digital signal related to the value of the second capacitor based on the amount of charge released by the second plate of the third capacitor.

[0008] Wherein, the first capacitance value is the difference between the capacitance values ​​of the first capacitor and the second capacitor, the second capacitance value is the sum of the capacitance values ​​of the first capacitor and the second capacitor, and the difference between the capacitance values ​​of the first capacitor and the second capacitor changes as the detected object moves.

[0009] The sum of the capacitance values ​​of the first capacitor and the second capacitor does not change with the movement of the object being detected, or the series capacitance value of the first capacitor and the second capacitor does not change with the movement of the object being detected.

[0010] Secondly, this application provides a chip including the capacitor module detection circuit as described in the first aspect.

[0011] Thirdly, this application provides an optical lens movement detection device, comprising:

[0012] The chip as described in the second aspect has a first output pin, a second output pin, and a first input pin;

[0013] The capacitor module includes a first capacitor, a second capacitor, and a third capacitor, and the first plates of the first capacitor, the second capacitor, and the third capacitor are electrically connected to each other.

[0014] The difference between the capacitance values ​​of the first capacitor and the second capacitor changes as the object being detected moves.

[0015] The sum of the capacitance values ​​of the first capacitor and the second capacitor does not change with the movement of the object being detected, or the series capacitance value of the first capacitor and the second capacitor does not change with the movement of the object being detected.

[0016] The first output pin is connected to the second plate of the first capacitor to control the voltage of the second plate of the first capacitor. The second output pin is connected to the second plate of the second capacitor to control the voltage of the second plate of the second capacitor. The first input pin is connected to the second plate of the third capacitor to measure the movement distance of the optical lens based on the amount of charge released from the second plate of the third capacitor.

[0017] Fourthly, this application provides a focusing motor, including an optical lens movement detection device as described in the third aspect.

[0018] Fifthly, this application provides a camera module including a focusing motor as described in the fourth aspect.

[0019] Sixthly, this application provides an electronic device including a camera module as described in the fifth aspect.

[0020] In this application, during the process of the voltage control module changing the voltage of the second plate of the first capacitor and the second plate of the second capacitor, the measurement module can output a first digital signal related to the difference in capacitance values ​​of the first and second capacitors based on the amount of charge released by the second plate of the third capacitor, and can output a second digital signal related to the sum of capacitance values ​​of the first and second capacitors based on the amount of charge released by the second plate of the third capacitor. Since the sum of capacitance values ​​of the first and second capacitors does not change with the movement of the detection object (e.g., an optical lens), or the series capacitance value of the first and second capacitors does not change with the movement of the detection object, while the difference in capacitance values ​​of the first and second capacitors changes with the movement of the detection object, the sum of capacitance values ​​of the first and second capacitors (or the series capacitance value of the first and second capacitors) represents a fixed position, while the difference in capacitance values ​​of the first and second capacitors represents the movement distance of the detection object. Therefore, the movement distance of the detection object can be calculated using the first and second digital signals.

[0021] Meanwhile, since the capacitor module detection circuit of this application controls the voltage of the second plate of the first capacitor and the second plate of the second capacitor, and receives the charge released by the second plate of the third capacitor, the capacitor module detection circuit of this application only connects the second plates of the first capacitor, the second plate of the second capacitor, and the second plate of the third capacitor, without connecting the first plate and the second plate of the same capacitor (i.e., one moving plate and another fixed plate). Ultimately, the capacitor module detection circuit of this application can accurately determine the moving position of the detection object, while also helping to reduce the manufacturing difficulty of the optical lens moving detection device. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying 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.

[0023] Figure 1 This is a schematic diagram of a motion distance detection scheme for optical lenses in related technologies;

[0024] Figure 2 This invention illustrates a connection diagram between the photocapacitive module detection circuit and the capacitor module in an embodiment of this application.

[0025] Figure 3 This paper shows a schematic diagram of the arrangement of relevant capacitors in an embodiment of this application;

[0026] Figure 4 A schematic diagram showing another arrangement of the relevant capacitors in an embodiment of this application is shown;

[0027] Figure 5 A schematic diagram showing another arrangement of the relevant capacitors in an embodiment of this application is shown;

[0028] Figure 6 A schematic diagram showing another arrangement of the relevant capacitors in an embodiment of this application is shown;

[0029] Figure 7 A schematic diagram showing another arrangement of the relevant capacitors in an embodiment of this application is shown;

[0030] Figure 8 A schematic diagram showing another arrangement of the relevant capacitors in an embodiment of this application is shown;

[0031] Figure 9 A schematic diagram of a capacitor module detection circuit in an embodiment of this application is shown;

[0032] Figure 10 This paper shows a schematic diagram of a state switching of the capacitor module detection circuit in an embodiment of this application;

[0033] Figure 11 This illustration shows another state switching diagram of the capacitor module detection circuit in an embodiment of this application;

[0034] Figure 12 Another schematic diagram of the capacitor module detection circuit in an embodiment of this application is shown;

[0035] Figure 13 Another schematic diagram of the capacitor module detection circuit in an embodiment of this application is shown;

[0036] Figure 14 Another schematic diagram of the capacitor module detection circuit in an embodiment of this application is shown;

[0037] Figure 15 Another schematic diagram of the capacitor module detection circuit in an embodiment of this application is shown;

[0038] Figure 16 Another schematic diagram of the capacitor module detection circuit in an embodiment of this application is shown;

[0039] Figure 17 Another schematic diagram of the capacitor module detection circuit in an embodiment of this application is shown;

[0040] Figure 18 Another schematic diagram of the capacitor module detection circuit in an embodiment of this application is shown;

[0041] Figure 19 Another schematic diagram of the capacitor module detection circuit in an embodiment of this application is shown;

[0042] Figure 20 Another schematic diagram of the capacitor module detection circuit in an embodiment of this application is shown;

[0043] Figure 21 Another schematic diagram of the capacitor module detection circuit in an embodiment of this application is shown.

[0044] Among them, 100 is the capacitor module detection circuit, 110 is the voltage control module, 111 is the first clock output unit, 112 is the second clock output unit, 120 is the measurement module, 200 is the capacitor module, 210 is the first capacitor, 211 is the first plate of the first capacitor, 212 is the second plate of the first capacitor, 220 is the second capacitor, 221 is the first plate of the second capacitor, 222 is the second plate of the second capacitor, 230 is the third capacitor, 231 is the first plate of the third capacitor, and 232 is the second plate of the second capacitor.

[0045] First digital signal Dout1, second digital signal Dout2, first reference voltage Vref1, second reference voltage Vref2;

[0046] First switch S1, second switch S2, third switch S3, fourth switch S4, first clock signal CLK1, second clock signal CLK2;

[0047] First operational amplifier OP1, integrating capacitor CI, integrating switch SI, feedback resistor RI, analog-to-digital converter ADC, demodulation unit Demod, first integrating switch SIn, second integrating switch SIp, quantizer Qt, digital-to-analog converter DAC, current mirror CM. 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, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of the stated features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0050] In this application, 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.

[0051] It should be noted that in the embodiments of this application, "connection" can be understood as electrical connection. The connection between two electrical components can be a direct or indirect connection between the two electrical components. For example, the connection between A and B can be a direct connection between A and B, or an indirect connection between A and B through one or more other electrical components.

[0052] Currently, in order to reduce the cost of optical lens movement distance detection solutions, some solutions use a capacitor structure to detect the movement distance of the optical lens. This method calculates the distance / area between the two plates of the capacitor by measuring the capacitance value, thereby determining the movement distance of the optical lens.

[0053] See Figure 1 , Figure 1A schematic diagram of a motion distance detection scheme for an optical lens in the related art is shown. In this scheme, one plate of a capacitor is set on a moving structure (e.g., a moving bracket that mounts the optical lens), while the other plate is set on a fixed structure (e.g., a fixed bracket that mounts the moving bracket to make it move). At the same time, the readout circuit needs to be electrically connected to both plates simultaneously, and then the capacitance can be calculated according to the capacitance calculation formula.

[0054] C = Q / U = εS / 4πkd

[0055] Where C is the capacitance of the capacitor being tested, Q is the charge accumulated in the capacitor, U is the voltage difference between the two plates, ε is the dielectric constant of the medium between the plates, k is the electrostatic constant, S is the area of ​​the plates facing each other, and d is the distance between the plates.

[0056] When the optical lens causes the electrode plates to move away from or closer to each other along the X-axis, changing the distance between the electrode plates, the distance the optical lens moves is:

[0057]

[0058] Where D is the moving distance of the optical lens, and d0 is the initial plate spacing of the capacitor.

[0059] As can be seen, the readout circuit needs to be electrically connected to both a stationary plate and a moving plate simultaneously, and detect the voltage across the capacitor after injecting a fixed amount of charge into the capacitor in order to obtain the distance the optical lens moves along the X-axis. However, the readout circuit requires two wires to be electrically connected to both a stationary plate and a moving plate, which is very difficult for miniaturized camera lenses (such as mobile phone camera devices) (for example, it is difficult to route wires in the moving structure).

[0060] Therefore, embodiments of this application provide a capacitor module detection circuit, a chip, an optical lens movement detection device, a focusing motor, a camera module, and an electronic device, which will be described in detail below.

[0061] Before introducing the capacitor module detection circuit 100 of this application, let's first introduce the capacitor module 200 of this application and the connection relationship between the capacitor module detection circuit 100 and the capacitor module 200.

[0062] First, refer to Figure 2 , Figure 2The diagram illustrates a connection between the photocapacitor module detection circuit 100 and the capacitor module 200 in an embodiment of this application. The capacitor module 200 includes a first capacitor 210, a second capacitor 220, and a third capacitor 230. The first plate 211 of the first capacitor 210, the first plate 221 of the second capacitor 220, and the first plate 231 of the third capacitor 230 are electrically connected to each other. The second plates 212 of the first capacitor 210, the second plate 222 of the second capacitor 220, and the second plate 232 of the third capacitor 230 are connected to the capacitor module detection circuit 100. In other words, the capacitor module detection circuit 100 of this application only connects the second plates 212, 222, and 232 of each capacitor, without connecting the first and second plates of the same capacitor (i.e., one movable plate and another fixed plate).

[0063] In this embodiment, the difference in capacitance between the first capacitor 210 and the second capacitor 220 changes with the movement of the object being detected; and the sum of the capacitance values ​​of the first capacitor 210 and the second capacitor 220 does not change with the movement of the object being detected, or the series capacitance value of the first capacitor 210 and the second capacitor 220 does not change with the movement of the object being detected. For ease of understanding, this application uses an optical lens as an example to exemplify how to arrange the plates of the first capacitor 210, the second capacitor 220, and the third capacitor 230, such that the sum of the capacitance values ​​of the first capacitor 210 and the second capacitor 220 does not change with the movement of the object being detected, or the series capacitance value of the first capacitor 210 and the second capacitor 220 does not change with the movement of the object being detected, while the difference in capacitance values ​​of the first capacitor 210 and the second capacitor 220 changes with the movement of the object being detected. It should be understood that the capacitor module detection circuit 100 of this application can be applied to, but is not limited to, optical lens movement detection schemes.

[0064] As an example, see Figure 3 , Figure 3 This paper shows a schematic diagram of the arrangement of relevant capacitors in an embodiment of this application. Figure 3 In the optical lens 1, the moving structure includes a movable support 2 and a stator support 3. The optical lens 1 is fixedly connected to the movable support 2, and the movable support 2 can move left and right relative to the stator support 3. The left and right movement of the optical lens 1 is achieved through the relative movement of the movable support 2 and the stator support 3. Understandably, the moving structure of the optical lens 1 may also include other components, such as a motor that drives the movable support 2, or a coil, magnet, etc., that drive the movable support 2.

[0065] Specifically, the first plate 211 of the first capacitor 210, the first plate 221 of the second capacitor 220, and the first plate 231 of the third capacitor 230 are electrically connected to each other, and the first plate 211 of the first capacitor 210, the first plate 221 of the second capacitor 220, and the first plate 231 of the third capacitor 230 are fixed on the moving bracket 2. Specifically, the first electrode 211 of the first capacitor 210 is fixed on the left side of the mover support 2, the first electrode 221 of the second capacitor 220 is fixed on the right side of the mover support 2, and the first electrode 231 of the third capacitor 230 is fixed on the bottom of the mover support 2; the second electrode 212 of the first capacitor 210 is fixed on the inner wall of the left side of the stator support 3 and is opposite to the first electrode 211 of the first capacitor 210; the second electrode 222 of the second capacitor 220 is fixed on the inner wall of the right side of the stator support 3 and is opposite to the first electrode 221 of the second capacitor 220; and the second electrode 232 of the third capacitor 230 is fixed on the inner wall of the bottom of the stator support 3 and is opposite to the first electrode 231 of the third capacitor 230.

[0066] It can be seen that, Figure 3 In the process, when the optical lens 1 moves left and right, the facing area of ​​the plates of the first capacitor 210, the second capacitor 220, and the third capacitor 230 remains unchanged, and the distance between the plates of the third capacitor 230 also remains unchanged. However, the distance between the plates of one of the first capacitor 210 and the second capacitor 220 decreases, while the distance between the plates of the other increases. The sum of the distances between the plates of the first capacitor 210 and the second capacitor 220 remains unchanged. According to the capacitance formula, for... Figure 3 Regarding the first capacitor 210, the second capacitor 220, and the third capacitor 230, the series capacitance value of the first capacitor 210 and the second capacitor 220 does not change with the left and right movement of the optical lens 1, while the difference between the capacitance values ​​of the first capacitor 210 and the second capacitor 220 changes with the left and right movement of the optical lens 1.

[0067] As another exemplary embodiment, see Figure 4 , Figure 4 This illustration shows another schematic diagram of the arrangement of the relevant capacitors in an embodiment of this application. Figure 4 In this configuration, the moving bracket 2 can move up and down relative to the stator bracket 3, so that the optical lens 1 can move up and down through the relative movement of the moving bracket 2 and the stator bracket 3.

[0068] Specifically, the first plate 211 of the first capacitor 210, the first plate 221 of the second capacitor 220, and the first plate 231 of the third capacitor 230 are electrically connected to each other, and the first plates 211, 221, and 231 of the first capacitor 210, the second plate 221 of the second capacitor 220, and the first plate 231 of the third capacitor 230 are fixed on the mover support 2, and the second plates 212, 222, and 232 of the first capacitor 210, the second plate 222 of the second capacitor 220, and the second plate 232 of the third capacitor 230 are fixed on the stator support 3. The first plate 211 of the first capacitor 210 and the first plate 221 of the second capacitor 220 are a single integral plate. Part of this integral plate is opposite to the second plate 212 of the first capacitor 210 to form the first capacitor 210, and another part is opposite to the second plate 222 of the second capacitor 220 to form the second capacitor 220.

[0069] exist Figure 4 In the process, when the optical lens 1 moves up and down, the distance between the plates of the first capacitor 210, the second capacitor 220, and the third capacitor 230 remains unchanged, and the area of ​​the plates facing each other in the third capacitor 230 also remains unchanged. However, the area of ​​the plates facing each other in the first capacitor 210 and the second capacitor 220 decreases, while the area of ​​the plates facing each other in the second capacitor increases. The sum of the areas of the plates facing each other in the first capacitor 210 and the second capacitor 220 remains unchanged. According to the capacitance formula, for... Figure 4 Regarding the first capacitor 210, the second capacitor 220, and the third capacitor 230, the sum of the capacitance values ​​of the first capacitor 210 and the second capacitor 220 does not change with the left-right movement of the optical lens 1, while the difference between the capacitance values ​​of the first capacitor 210 and the second capacitor 220 changes with the up-down movement of the optical lens 1.

[0070] It should be noted that the first plates 211 of the first capacitor 210, the first plates 221 of the second capacitor 220, and the first plates 231 of the third capacitor 230, which are electrically connected to each other in the embodiments of this application, can be independent plates that are electrically connected by wires, for example, Figure 3 As shown, the first plate 211 of the first capacitor 210, the first plate 221 of the second capacitor 220, and the first plate 231 of the third capacitor 230 are electrically connected by wires. Alternatively, at least two of the three capacitors can be integrally formed plates. For example, in... Figure 4 In the first capacitor 210, the first plate 211 and the first plate 221 of the second capacitor 220 are a single integral plate; for example, see [reference needed]. Figure 5 , Figure 5The diagram shows another arrangement of the capacitors in the embodiment of this application. The first plate 211 of the first capacitor 210, the first plate 221 of the second capacitor 220, and the first plate 231 of the third capacitor 230 are an integral plate, which can eliminate the need for the wires that electrically connect the first plate 211 of the first capacitor 210, the first plate 221 of the second capacitor 220, and the first plate 231 of the third capacitor 230.

[0071] Understandably, the above arrangement of the first capacitor 210, the second capacitor 220, and the third capacitor 230 is merely an exemplary embodiment in which the sum of the capacitance values ​​(or the series capacitance values) of the first capacitor 210 and the second capacitor 220 does not change with the movement of the detected object, while the difference between the capacitance values ​​of the first capacitor 210 and the second capacitor 220 changes with the movement of the detected object. Those skilled in the art can make equivalent modifications under the guidance of this application.

[0072] For example, see Figure 6 , Figure 6 This illustration shows another arrangement of the capacitors in an embodiment of this application, wherein the second plate 212 of the first capacitor 210 and the second plate 222 of the second capacitor 220 are complementary trapezoidal plates. This allows the facing area of ​​one of the plates of the first capacitor 210 and the second capacitor 220 to decrease and the facing area of ​​the other plate to increase when the optical lens 1 moves up and down, but the sum of the facing areas of the plates of the first capacitor 210 and the second capacitor 220 remains unchanged. Therefore, the sum of the capacitance values ​​of the first capacitor 210 and the second capacitor 220 does not change with the movement of the optical lens 1, while the difference in capacitance values ​​between the first capacitor 210 and the second capacitor 220 changes with the movement of the optical lens 1.

[0073] For example, see Figure 7 , Figure 7 This illustration shows another arrangement of the capacitors in an embodiment of this application. Unlike other embodiments, the moving bracket 2 of the optical lens 1 includes an image stabilization bracket 202 and a focusing bracket 201. The image stabilization bracket 202 can move in the planes containing the X and Y axes, and the focusing bracket 201 can move along the Z axis on the image stabilization bracket 202. When the first plate 211 of the first capacitor 210, the first plate 221 of the second capacitor 220, and the first plate 231 of the third capacitor 230 are fixed on the focusing bracket 201, the capacitor module detection circuit 100 can detect the focusing position of the optical lens 1.

[0074] For example, see Figure 8 , Figure 8This illustration shows another arrangement of the capacitors in an embodiment of this application. Unlike other embodiments, the moving bracket 2 of the optical lens 1 includes a first image stabilization bracket 203, a second image stabilization bracket 204, and a first focusing bracket 205. The first image stabilization bracket 203 can move along the X-axis, the second image stabilization bracket 204 can move along the Y-axis, and the first focusing bracket 205 can move along the Z-axis. When the first plate 211 of the first capacitor 210, the first plate 221 of the second capacitor 220, and the first plate 231 of the third capacitor 230 are fixed on the first focusing bracket 205, the capacitor module detection circuit 100 can detect the focusing position of the optical lens 1.

[0075] Understandably, when the first plate 211 of the first capacitor 210, the first plate 221 of the second capacitor 220, and the first plate 231 of the third capacitor 230 are fixed on other supports (e.g., image stabilization support 202, first image stabilization support 203, and second image stabilization support 204), the movement position detection of the optical lens 1 in other directions (e.g., optical image stabilization function) can be realized.

[0076] The capacitor module detection circuit 100 for detecting the capacitor module 200 in this application will now be described. (See attached document.) Figure 9 , Figure 9 A schematic diagram of a capacitor module detection circuit 100 in an embodiment of this application is shown, wherein the capacitor module detection circuit 100 includes a voltage control module 110 and a measurement module 120.

[0077] Specifically, the voltage control module 110 is used to control the voltage of the second plate 212 of the first capacitor 210 and the second plate 222 of the second capacitor 220, so that the second plate 232 of the third capacitor 230 releases charge, and the measurement module 120 receives the charge released by the second plate 232 of the third capacitor 230 and outputs a first digital signal Dout1 related to the first capacitance value and a second digital signal Dout2 related to the second capacitance value.

[0078] In some embodiments of this application, the voltage control module 110 may include a switching circuit to switch the voltage signals connected to the second plate 212 of the first capacitor 210 and the second plate 222 of the second capacitor 220, thereby controlling the voltages of the second plates 212 of the first capacitor 210 and the second plate 222 of the second capacitor 220. In some embodiments of this application, the voltage control module 110 may include a clock signal generation circuit. The clock signal output by the clock signal generation circuit periodically changes between high and low levels, thereby controlling the voltages of the second plates 212 of the first capacitor 210 and the second plate 222 of the second capacitor 220 using the clock signal.

[0079] The measurement module 120 is used to output a first digital signal Dout1 related to the first capacitance value based on the amount of charge released by the second plate 232 of the third capacitor 230 during the process of the voltage control module 110 changing the voltage of the second plate 212 of the first capacitor 210 and the second plate 222 of the second capacitor 220, and to output a second digital signal Dout2 related to the second capacitance value based on the amount of charge released by the second plate 232 of the third capacitor 230. The first capacitance value is the difference between the capacitance values ​​of the first capacitor 210 and the second capacitor 220, and the second capacitance value is the sum of the capacitance values ​​of the first capacitor 210 and the second capacitor 220.

[0080] For example, with Figure 3 The capacitor arrangement ensures that the series capacitance of the first capacitor 210 and the second capacitor 220 does not change with the movement of the detected object. Taking the difference between the capacitance values ​​of the first capacitor 210 and the second capacitor 220 as an example, which changes with the movement of the detected object, the first capacitance value and the second capacitance value satisfy the following relationship:

[0081]

[0082] d0 = d1 + d2

[0083] Wherein, C1 is the capacitance value of the first capacitor 210, C2 is the capacitance value of the second capacitor 220, S0 is the area of ​​the plates of the first capacitor 210 and the second capacitor 220 facing each other, d1 is the distance between the plates of the first capacitor 210, d2 is the distance between the plates of the second capacitor 220, d0 is the sum of the distances between the plates of the first capacitor 210 and the second capacitor 220, and d0 remains constant.

[0084] Assume that the first digital signal Dout1 and the first capacitor value, and the second digital signal Dout2 and the second capacitor value, satisfy the following relationship:

[0085] Dout1=(C1-C2)*k1

[0086] Dout2=(C1+C2)*k2

[0087] Where C1 is the capacitance value of the first capacitor 210, C2 is the capacitance value of the second capacitor 220, and k1 and k2 are conversion coefficients.

[0088] It can be known that:

[0089]

[0090]

[0091] Therefore, the difference between the plate spacing of the first capacitor 210 and the plate spacing of the second capacitor 220 satisfies the following formula:

[0092]

[0093] exist Figure 3 From the above, it can be seen that the difference between the plate spacing of the first capacitor 210 and the plate spacing of the second capacitor 220 is twice the moving distance of the optical lens. Therefore, the moving distance D of the optical lens can be calculated using the following formula:

[0094]

[0095] As can be seen, since the sum of the plate spacing of the first capacitor 210 and the second capacitor 220 remains unchanged, after determining the first digital signal Dout1 corresponding to the sum of the capacitance values ​​of the first capacitor 210 and the second capacitor 220, and the second digital signal Dout2 corresponding to the difference in capacitance values ​​of the first capacitor 210 and the second capacitor 220, the moving distance of the optical lens can be calculated according to the above formula.

[0096] Therefore, in the process of the voltage control module 110 changing the voltage of the second plate 212 of the first capacitor 210 and the second plate 222 of the second capacitor 220, the measurement module 120 can output a first digital signal Dout1 related to the sum of the capacitance values ​​of the first capacitor 210 and the second capacitor 220 based on the amount of charge released by the second plate 232 of the third capacitor 230, and can output a second digital signal Dout2 related to the difference in capacitance values ​​of the first capacitor 210 and the second capacitor 220 based on the amount of charge released by the second plate 232 of the third capacitor 230. Since the sum of the capacitance values ​​of the first capacitor 210 and the second capacitor 220 does not change with the detection pair... The capacitance value of the first capacitor 210 and the second capacitor 220 changes with the movement of the object being detected, or the series capacitance value of the first capacitor 210 and the second capacitor 220 does not change with the movement of the object being detected, while the difference between the capacitance values ​​of the first capacitor 210 and the second capacitor 220 changes with the movement of the object being detected. Therefore, the sum of the capacitance values ​​of the first capacitor 210 and the second capacitor 220 (or the series capacitance value of the first capacitor 210 and the second capacitor 220) represents a fixed position, while the difference between the capacitance values ​​of the first capacitor 210 and the second capacitor 220 represents the moving distance of the object being detected. Thus, the moving distance of the object being detected can be calculated using the first digital signal Dout1 and the second digital signal Dout2.

[0097] Meanwhile, since the capacitor module detection circuit 100 of this application controls the voltage of the second plate 212 of the first capacitor 210 and the second plate 222 of the second capacitor 220, and receives the charge released by the second plate 232 of the third capacitor 230, the capacitor module detection circuit 100 of this application only connects the second plate 212 of the first capacitor 210, the second plate 222 of the second capacitor 220 and the second plate 232 of the third capacitor 230, without connecting the first plate and the second plate of the same capacitor (i.e., one moving plate and another fixed plate). In the end, the capacitor module detection circuit 100 of this application can accurately determine the moving position of the detection object, and also helps to reduce the manufacturing difficulty of the optical lens moving detection device.

[0098] In some embodiments of this application, during the process of the measurement module 120 outputting a first digital signal Dout1 related to the first capacitance value based on the amount of charge released by the second plate 232 of the third capacitor 230, the voltage changes of the second plate 212 of the first capacitor 210 and the second plate 222 of the second capacitor 220 are opposite. For example, in one unit time, the second plate 212 of the first capacitor 210 is 5V and the second plate 222 of the second capacitor 220 is 0V. In the next unit time, the second plate 212 of the first capacitor 210 is 0V and the second plate 222 of the second capacitor 220 is 5V.

[0099] Meanwhile, during the process of the measurement module 120 outputting a second digital signal Dout2 related to the second capacitor value based on the amount of charge released by the second plate 232 of the third capacitor 230, the voltage changes of the second plate 212 of the first capacitor 210 and the second plate 222 of the second capacitor 220 are the same. For example, in one unit time, the second plate 212 of the first capacitor 210 and the second plate 222 of the second capacitor 220 are both 3V, and in the next unit time, the second plate 212 of the first capacitor 210 and the second plate 222 of the second capacitor 220 are both -2V.

[0100] In some embodiments of this application, the voltage control module 110 has a first operating state, a second operating state, a third operating state, and a fourth operating state; in the first operating state, the voltage control module 110 controls the voltage of the second plate 212 of the first capacitor 210 to be a first reference voltage Vref1, and controls the voltage of the second plate 222 of the second capacitor 220 to be a second reference voltage Vref2; in the second operating state, the voltage control module 110 controls the voltage of the second plate 212 of the first capacitor 210 to be a second reference voltage Vref2, and controls the voltage of the second plate 222 of the second capacitor 220 to be a second reference voltage Vref2. In the third operating state, the voltage control module 110 controls the voltage of the second plate 212 of the first capacitor 210 to be the first reference voltage Vref1, and controls the voltage of the second plate 222 of the second capacitor 220 to be the first reference voltage Vref1; in the fourth operating state, the voltage control module 110 controls the voltage of the second plate 212 of the first capacitor 210 to be the second reference voltage Vref2, and controls the voltage of the second plate 222 of the second capacitor 220 to be the second reference voltage Vref2.

[0101] Specifically, see Figure 10 , Figure 10 This illustration shows a state switching diagram of the capacitor module detection circuit 100 in an embodiment of this application. When the voltage control module 110 switches from a first operating state to a second operating state, since there is no charge loss on the first plate 211 of the first capacitor 210, the first plate 221 of the second capacitor 220, and the first plate 231 of the third capacitor 230, according to the law of charge conservation:

[0102] (VX1-Vref1)*C1+(VX1-Vref2)*C2+VX1*C3=(VX2-Vref2)*C1+(VX2-Vref1

[0103] )*C2+VX2*C3

[0104] Wherein, C3 is the capacitance value of the third capacitor 230, VX1 is the voltage of the first plate of the first capacitor 210, the second capacitor 220 and the third capacitor 230 in the first working state, and VX2 is the voltage of the first plate of the first capacitor 210, the second capacitor 220 and the third capacitor 230 in the second working state.

[0105] After conversion according to the above formula, we can know that:

[0106] (VX1-VX2)*(C1+C2+C3)=(C1-C2)*(Vref1-Vref2)

[0107] The charge released by the second plate 232 of the third capacitor 230 satisfies the following formula:

[0108] △Q1=(VX1-VX2)*C3

[0109] Wherein, △Q1 is the amount of charge released by the second plate 232 of the third capacitor 230 when the voltage control module 110 switches from the first working state to the second working state.

[0110] Based on the above formula, the charge released by the second plate 232 of the third capacitor 230 can be calculated using the following formula:

[0111]

[0112] As can be seen, the above formula contains terms C1-C2. Therefore, when the voltage control module 110 switches from the first working state to the second working state, the amount of charge released by the second plate 232 of the third capacitor 230 is related to the difference in capacitance values ​​between the first capacitor 210 and the second capacitor 220. Therefore, when the voltage control module 110 switches from the first working state to the second working state, the measurement module 120 can output a first digital signal Dout1 related to the first capacitance value (i.e., the difference in capacitance values ​​between the first capacitor 210 and the second capacitor 220) based on the amount of charge released by the second plate 232 of the third capacitor 230.

[0113] Similarly, see Figure 11 , Figure 11 This paper shows another state switching diagram of the capacitor module detection circuit 100 in an embodiment of this application. When the voltage control module 110 switches from the third operating state to the fourth operating state, since there is no charge loss on the first plate 211 of the first capacitor 210, the first plate 221 of the second capacitor 220, and the first plate 231 of the third capacitor 230, according to the law of charge conservation:

[0114] (VX3-Vref1)*C1+(VX3-Vref1)*C2+VX3*C3=(VX4-Vref2)*C1+(VX4-Vref2

[0115] )*C2+VX4*C3

[0116] Wherein, VX3 is the voltage of the first plate of the first capacitor 210, the second capacitor 220 and the third capacitor 230 in the third working state, and VX4 is the voltage of the first plate of the first capacitor 210, the second capacitor 220 and the third capacitor 230 in the fourth working state.

[0117] After conversion according to the above formula, we can know that:

[0118] (VX3-VX4)*(C1+C2+C3)=(C1+C2)*(Vref1-Vref2)

[0119] The charge released by the second plate 232 of the third capacitor 230 satisfies the following formula:

[0120] △Q2=(VX3-VX4)*C3

[0121] Wherein, △Q1 is the amount of charge released by the second plate 232 of the third capacitor 230 when the voltage control module 110 switches from the third working state to the fourth working state.

[0122] According to the above formula, the charge released by the second plate 232 of the third capacitor 230 can be calculated using the following formula:

[0123]

[0124] As can be seen, the above formula contains the term C1+C2. Therefore, when the voltage control module 110 switches from the third working state to the fourth working state, the amount of charge released by the second plate 232 of the third capacitor 230 is related to the sum of the capacitance values ​​of the first capacitor 210 and the second capacitor 220. Therefore, when the voltage control module 110 switches from the third working state to the fourth working state, the measurement module 120 can output a second digital signal Dout2 related to the second capacitance value (i.e., the sum of the capacitance values ​​of the first capacitor 210 and the second capacitor 220) based on the amount of charge released by the second plate 232 of the third capacitor 230.

[0125] It should be noted that in the embodiments of this application, the first reference voltage Vref1 and the second reference voltage Vref2 are not equal. Those skilled in the art can select an appropriate reference voltage according to actual needs. For example, the first reference voltage Vref1 can be greater than the second reference voltage Vref2, the second reference voltage Vref2 is the ground terminal voltage, and the first reference voltage Vref1 is the power supply terminal voltage. Alternatively, the first reference voltage Vref1 can be less than the second reference voltage Vref2, the second reference voltage Vref2 is the power supply terminal voltage, and the first reference voltage Vref1 is the ground terminal voltage.

[0126] It should be noted that the capacitor module detection circuit 100 of this application can eliminate multiple interference factors and improve the detection accuracy of the optical lens movement distance. For example, in an embodiment where the first electrode plate 211 of the first capacitor 210, the first electrode plate 221 of the second capacitor 220, and the first electrode plate 231 of the third capacitor 230 are a single integral electrode plate, parasitic capacitance may exist in the capacitor module 200 due to the influence of other metal structural components (e.g., metal casing). For example, see [reference needed]. Figure 12 , Figure 12Another schematic diagram of the capacitor module detection circuit 100 in this application embodiment is shown. Other metal structural components and the integral plate form parasitic capacitance. Although parasitic capacitance exists, the solution of this application will not be affected by parasitic capacitance. The following is a detailed description.

[0127] Specifically, when the voltage control module 110 switches from the first operating state to the second operating state, since there is no charge loss in the first plate 211 of the first capacitor 210, the first plate 221 of the second capacitor 220, and the first plate 231 of the third capacitor 230, according to the law of charge conservation:

[0128] (VX1-Vref1)*C1+(VX1-Vref2)*C2+VX1*C3+VX1*CP=(VX2-Vref2)*C1+(

[0129] VX2-Vref1)*C2+VX2*C3+VX2*CP

[0130] Where CP is the capacitance value of the parasitic capacitance.

[0131] After conversion according to the above formula, we can know that:

[0132] (VX1-VX2)*(C1+C2+C3+CP)=(C1-C2)*(Vref1-Vref2)

[0133] Therefore, the charge released by the second plate 232 of the third capacitor 230 can be calculated using the following formula:

[0134]

[0135] Similarly, when the voltage control module 110 switches from the third operating state to the fourth operating state, the charge released by the second plate 232 of the third capacitor 230 can be calculated using the following formula:

[0136]

[0137] Suppose that the first digital signal Dout1, the second digital signal Dout2, and the charge released by the second plate 232 of the third capacitor 230 satisfy the following relationship:

[0138] Dout1=△Q1*kx

[0139] Dou2=△Q2*ky

[0140] Where kx and ky are conversion coefficients.

[0141] Therefore, we can conclude that:

[0142]

[0143] Finally, combining the aforementioned formula for calculating the movement distance D of the optical lens, we can derive the movement distance D of the optical lens from the following formula:

[0144]

[0145] As can be seen, the above formula cancels out the Vref1-Vref2 term, the C1+C2+C3+CP term, and the C3 term. Therefore, the capacitor module detection circuit 100 of this application will not be affected by the accuracy of the first reference voltage Vref1, the accuracy of the second reference voltage Vref2, the parasitic capacitance, or the third capacitor 230, which is beneficial to improving the detection accuracy of the optical lens movement distance.

[0146] It should be noted that, as shown above, the capacitance value of the third capacitor does not affect the calculation of the optical lens's movement distance D. Therefore, in the aforementioned... Figures 3 to 8 The fact that the capacitance value of the third capacitor remains fixed is only an exemplary embodiment of this application. In reality, changes in the capacitance value of the third capacitor will not affect the detection accuracy of the optical lens movement distance D in this application.

[0147] In some embodiments of this application, such as the embodiment where the voltage control module 110 includes a switching circuit, see [link to relevant documentation]. Figure 13 , Figure 13 Another schematic diagram of the capacitor module detection circuit 100 in an embodiment of this application is shown, wherein the voltage control module 110 includes a first switch S1, a second switch S2, a third switch S3, and a fourth switch S4; the first terminal of the first switch S1 is connected to a first reference voltage Vref1, and the second terminal of the first switch S1 is connected to the second plate 212 of the first capacitor 210; the first terminal of the second switch S2 is connected to a second reference voltage Vref2, and the second terminal of the second switch S2 is connected to the second plate 212 of the first capacitor 210; the first terminal of the third switch S3 is connected to the first reference voltage Vref1, and the second terminal of the third switch S3 is connected to the second plate 222 of the second capacitor 220; the first terminal of the fourth switch S4 is connected to the second reference voltage Vref2, and the second terminal of the fourth switch S4 is connected to the second plate 222 of the second capacitor 220.

[0148] It should be noted that when the first switch S1 and the fourth switch S4 are closed, and the second switch S2 and the third switch S3 are open, the voltage of the second plate 212 of the first capacitor 210 is the first reference voltage Vref1, and the voltage of the second plate 222 of the second capacitor 220 is the second reference voltage Vref2. This corresponds to the first working state of the voltage control module 110.

[0149] When the second switch S2 and the third switch S3 are closed, and the first switch S1 and the fourth switch S4 are open, the voltage of the second plate 212 of the first capacitor 210 is the second reference voltage Vref2, and the voltage of the second plate 222 of the second capacitor 220 is the first reference voltage Vref1. This corresponds to the second working state of the voltage control module 110.

[0150] When the first switch S1 and the third switch S3 are closed, and the second switch S2 and the fourth switch S4 are open, the voltage of the second plate 212 of the first capacitor 210 is the first reference voltage Vref1, and the voltage of the second plate 222 of the second capacitor 220 is the first reference voltage Vref1. This corresponds to the third working state of the voltage control module 110.

[0151] When the second switch S2 and the fourth switch S4 are closed, and the first switch S1 and the third switch S3 are open, the voltage of the second plate 212 of the first capacitor 210 is the second reference voltage Vref2, and the voltage of the second plate 222 of the second capacitor 220 is the second reference voltage Vref2. This corresponds to the fourth working state of the voltage control module 110.

[0152] It can be seen that by controlling the first switch S1, the second switch S2, the third switch S3 and the fourth switch S4, the voltage control module 110 can achieve the purpose of controlling the voltage of the second plate 212 of the first capacitor 210 and the second plate 222 of the second capacitor 220.

[0153] In some embodiments of this application, such as the embodiment where the voltage control module 110 includes a clock signal generation circuit, see [link to relevant documentation]. Figure 14 , Figure 14 Another schematic diagram of the capacitor module detection circuit 100 in an embodiment of this application is shown, wherein the voltage control module 110 includes a first clock output unit 111 and a second clock output unit 112; the first clock output unit 111 is used to output a first clock signal CLK1 with a high level of the first reference voltage Vref1 and a low level of the second reference voltage Vref2; the second clock output unit 112 is used to output a second clock signal CLK2 with a high level of the first reference voltage Vref1 and a low level of the second reference voltage Vref2; wherein the first clock signal CLK1 and the second clock signal CLK2 are out of phase.

[0154] It should be noted that when the first clock output unit 111 inputs the first clock signal CLK1 to the second plate 212 of the first capacitor 210, and the second clock output unit 112 inputs the second clock signal CLK2 to the second plate 222 of the second capacitor 220, since the first clock signal CLK1 and the second clock signal CLK2 are out of phase, when the first clock signal CLK1 is high and the second clock signal is low, the voltage of the second plate 212 of the first capacitor 210 is the first reference voltage Vref1, and the voltage of the second plate 222 of the second capacitor 220 is the second reference voltage Vref2. This corresponds to the first operating state of the voltage control module 110. Conversely, when the first clock signal CLK1 is low and the second clock signal is high, the voltage of the second plate 212 of the first capacitor 210 is the second reference voltage Vref2, and the voltage of the second plate 222 of the second capacitor 220 is the first reference voltage Vref1. This corresponds to the second operating state of the voltage control module 110.

[0155] When the first clock output unit 111 inputs a first clock signal CLK1 to the second plate 212 of the first capacitor 210 and the second plate 222 of the second capacitor 220, or when the second clock output unit 112 inputs a second clock signal CLK2 to the second plate 212 of the first capacitor 210 and the second plate 222 of the second capacitor 220, if the first clock signal CLK1 or the second clock signal CLK2 is at a high level, then the voltage of the second plate 212 of the first capacitor 210 is the first reference voltage Vref1, and the voltage of the second plate 222 of the second capacitor 220 is the first reference voltage Vref1. This corresponds to the third working state of the voltage control module 110. Conversely, if the first clock signal CLK1 or the second clock signal CLK2 is at a low level, then the voltage of the second plate 212 of the first capacitor 210 is the second reference voltage Vref2, and the voltage of the second plate 222 of the second capacitor 220 is the second reference voltage Vref2. This corresponds to the fourth working state of the voltage control module 110.

[0156] As can be seen, the first clock signal CLK1 and the second clock signal CLK2 output by the first clock output unit 111 and the second clock output unit 112 can also achieve the purpose of voltage control module 110 on the second plate 212 of the first capacitor 210 and the second plate 222 of the second capacitor 220.

[0157] For example, the first clock output unit 111 and the second clock output unit 112 may include, but are not limited to, circuits that can generate clock signals, such as RC oscillators, crystal oscillators and phase-locked loops.

[0158] In some embodiments of this application, see Figure 15 , Figure 15 Another schematic diagram of the capacitor module detection circuit 100 in an embodiment of this application is shown, wherein the measurement module 120 includes a first operational amplifier OP1 and an integrating capacitor CI; the inverting input terminal of the first operational amplifier OP1 is connected to the second plate 232 of the third capacitor 230, and the non-inverting input terminal of the first operational amplifier OP1 is connected to the ground terminal; the first plate of the integrating capacitor CI is connected to the inverting input terminal of the first operational amplifier OP1, and the second plate of the integrating capacitor CI is connected to the output terminal of the first operational amplifier OP1.

[0159] It should be noted that the first operational amplifier OP1 and the integrating capacitor CI form an integrator. The integrator can integrate the charge output from the second plate 232 of the third capacitor 230, thereby converting the charge signal into a voltage signal. After the voltage signal is further converted into a digital signal by the relevant analog-to-digital conversion circuit, a first digital signal Dout1 related to the value of the first capacitor and a second digital signal Dout2 related to the value of the second capacitor can be output.

[0160] For example, in Figure 15 In the measurement module 120, there are also an integral switch SI and an analog-to-digital converter ADC; the first terminal of the integral switch SI is connected to the inverting input terminal of the first operational amplifier OP1, and the second terminal of the integral switch SI is connected to the output terminal of the first operational amplifier OP1; the input terminal of the analog-to-digital converter ADC is connected to the output terminal of the first operational amplifier OP1, and the analog-to-digital converter ADC is used to output a first digital signal Dout1 and a second digital signal Dout2.

[0161] When the voltage control module 110 is in the first operating state, with the first switch S1, the fourth switch S4, and the integrating switch S1 closed, and the second switch S2 and the third switch S3 open, due to the virtual short and virtual open characteristics of the first operational amplifier OP1, the voltage at the inverting input terminal of the first operational amplifier OP1 is the ground voltage. Similarly, when the voltage control module 110 is in the second operating state, with the first switch S1, the fourth switch S4, and the integrating switch open, and the second switch S2 and the third switch S3 closed, due to the virtual short and virtual open characteristics of the first operational amplifier OP1, the voltage at the inverting input terminal of the first operational amplifier OP1 is the ground voltage. Therefore, the first operating state switches to the second operating state. According to the law of charge conservation, we know that:

[0162] (VX1-Vref1)*C1+(VX1-Vref2)*C2+VX1*C3=(VX2-Vref2)*C1+(VX2-Vref1

[0163] )*C2+VX2*C3

[0164] After conversion according to the above formula, we can know that:

[0165] (VX1-VX2)*(C1+C2+C3)=(C1-C2)*(Vref1-Vref2)

[0166] The charge released by the second plate 232 of the third capacitor 230 satisfies the following formula:

[0167] △Q1=(VX2-VX1)*C3

[0168] It can be seen that the charge released by the second plate 232 of the third capacitor 230 can be calculated using the following formula:

[0169]

[0170] Since the charge released by the second plate 232 of the third capacitor 230 is integrated by the integrating capacitor CI, the voltage difference across the integrating capacitor CI is:

[0171]

[0172] Wherein, Vout1 is the voltage output by the integrating capacitor CI when the voltage control module 110 switches from the first working state to the third working state.

[0173] Finally, after the analog-to-digital converter (ADC) converts the voltage output from the integrating capacitor CI, the resulting first digital signal Dout1 is:

[0174] Dout1 = Vout1 * k

[0175] Where k is the conversion coefficient of the analog-to-digital converter (ADC).

[0176] Similarly, when the voltage control module 110 switches from the third operating state to the fourth operating state, the voltage output by the integrating capacitor CI is:

[0177]

[0178] Vout2 is the voltage output by the integrating capacitor CI when the voltage control module 110 switches from the third working state to the fourth working state.

[0179] Finally, after the analog-to-digital converter (ADC) converts the voltage output from the integrating capacitor CI, the resulting second digital signal Dout2 is:

[0180] Dout2 = Vout2 * k

[0181] As can be seen from the above formula, the first digital signal Dout1 is related to the difference in capacitance between the first capacitor 210 and the second capacitor 220, and the second digital signal Dout2 is related to the sum of capacitance between the first capacitor 210 and the second capacitor 220. Therefore, the moving distance of the detected object can be calculated using the first digital signal Dout1 and the second digital signal Dout2. The relevant calculation process can be found in the above content and will not be repeated here.

[0182] In some embodiments of this application, such as the embodiment where the voltage control module 110 includes a first clock output unit 111 and a second clock output unit 112, see [reference needed]. Figure 16 , Figure 16 Another schematic diagram of the capacitor module detection circuit 100 in an embodiment of this application is shown, wherein the measurement module 120 further includes a feedback resistor RI, a demodulation unit Demod, and an analog-to-digital converter ADC; the first end of the feedback resistor RI is connected to the inverting input terminal of the first operational amplifier OP1, and the second end of the feedback resistor RI is connected to the output terminal of the first operational amplifier OP1; the demodulation unit Demodulates the continuous voltage signal output by the first operational amplifier OP1 into a discrete signal, and the analog-to-digital converter ADC outputs a first digital signal Dout1 and a second digital signal Dout2 according to the discrete signal.

[0183] It should be noted that the feedback resistor RI, the first operational amplifier OP1, and the integrating capacitor CI form a charge amplifier. The charge amplifier can convert the charge signal output by the second capacitor 220 into a continuous voltage signal. The demodulation unit Demod can demodulate the continuous voltage signal output by the first operational amplifier OP1 into a discrete signal, such as the Vout1 and Vout2 voltage signals in the above embodiment. The analog-to-digital converter (ADC) performs analog-to-digital conversion and outputs the first digital signal Dout1 and the second digital signal Dout2. The moving distance of the detected object can then be calculated using the first digital signal Dout1 and the second digital signal Dout2.

[0184] In some embodiments of this application, see Figure 17 , Figure 17This illustration shows another schematic diagram of the capacitor module detection circuit 100 in an embodiment of this application. The measurement module 120 further includes a first integrating switch SIn, a second integrating switch SIp, a quantizer Qt, and a digital-to-analog converter (DAC). The first terminal of the first integrating switch SIn is connected to the inverting input terminal of the first operational amplifier OP1, and the second terminal of the first integrating switch SIn is connected to the output terminal of the first operational amplifier OP1. The first terminal of the second integrating switch SIp is connected to the inverting input terminal of the first operational amplifier OP1, and the second terminal of the second integrating switch SIp is connected to the first plate of the integrating capacitor CI. The quantizer Qt is connected to the output terminal of the first operational amplifier OP1, the input terminal of the DAC is connected to the output terminal of the quantizer Qt, and the output terminal of the DAC is connected to the inverting input terminal of the first operational amplifier OP1.

[0185] It should be noted that in the first and third operating states of the voltage control module 110, the first integrating switch SIn is closed, while the second integrating switch SIp is open; in the second and fourth operating states of the voltage control module 110, the first integrating switch SIn is open, while the second integrating switch SIp is closed, so that in the second and fourth operating states of the voltage control module 110, the integrating capacitor CI integrates the charge output from the second plate 232 of the third capacitor 230. Simultaneously, the first integrating switch SIn, the second integrating switch SIp, the integrating capacitor CI, the first operational amplifier OP1, the quantizer Qt, and the digital-to-analog converter DAC constitute part of the circuitry of the SD ADC (Sigma-Delta ADC). Therefore, based on the analog-to-digital conversion principle of the SD ADC, the charge input to the second plate 232 of the third capacitor 230 in multiple cycles can be quantized, and the first digital signal Dout1 and the second digital signal Dout2 can be output.

[0186] In some embodiments of this application, such as the embodiment where the voltage control module 110 includes a first clock output unit 111 and a second clock output unit 112, see [reference needed]. Figure 18 , Figure 18Another schematic diagram of the capacitor module detection circuit 100 in an embodiment of this application is shown, wherein the measurement module 120 further includes a demodulation unit Demod, a quantizer Qt, and a digital-to-analog converter DAC; the input terminal of the demodulation unit Demod is connected to the second plate 232 of the third capacitor 230, and the output terminal of the demodulation unit Demod is connected to the inverting input terminal of the first operational amplifier OP1. The demodulation unit Demod is used to demodulate the continuous charge signal output from the second plate 232 of the third capacitor 230 into a discrete signal; the quantizer Qt is connected to the output terminal of the first operational amplifier OP1, the input terminal of the digital-to-analog converter DAC is connected to the output terminal of the quantizer Qt, and the output terminal of the digital-to-analog converter DAC is connected to the inverting input terminal of the first operational amplifier OP1.

[0187] It should be noted that when the second plate 212 of the first capacitor 210 and the second plate 222 of the second capacitor 220 are connected to a clock signal, the second plate 232 of the third capacitor 230 outputs a continuous charge signal (i.e., a current signal). The demodulation unit Demod can demodulate the continuous charge signal output by the second plate 232 of the third capacitor 230 into a discrete signal. For example, the continuous charge signal can be demodulated into the ΔQ1 and ΔQ2 signals described in the aforementioned embodiment. After the SD ADC, composed of the integrating capacitor CI, the first operational amplifier OP1, the quantizer Qt, and the digital-to-analog converter DAC, performs analog-to-digital conversion on ΔQ1 and ΔQ2, the first digital signal Dout1 or the second digital signal Dout2 can be obtained.

[0188] In some embodiments of this application, such as the embodiment where the voltage control module 110 includes a first clock output unit 111 and a second clock output unit 112, see [reference needed]. Figure 19 , Figure 19 Another schematic diagram of the capacitor module detection circuit 100 in an embodiment of this application is shown, wherein, relative to Figure 18 The measurement module 120 also includes a current mirror CM; the input terminal of the current mirror CM is connected to the second plate 232 of the third capacitor 230, and the output terminal of the current mirror CM is connected to the input terminal of the demodulation unit Demod.

[0189] It should be noted that parasitic capacitance may also exist in the metal structure of the second plate 232 of the third capacitor 230 and the input port of the capacitor module detection circuit 100. This may cause the charge released by the second plate 232 of the third capacitor 230 to be absorbed by the parasitic capacitance, resulting in a decrease in measurement accuracy. In the above embodiment, since a current mirror CM is further provided, the current mirror CM can mirror the current signal formed by the charge released by the second plate 232 of the third capacitor 230 and input the mirrored current to the demodulation unit Demod for demodulation, ensuring that the measurement module 120 can normally output the first digital signal Dout1 and the second digital signal Dout2. At the same time, the current mirror CM isolates the influence of parasitic capacitance between the second plate 232 of the third capacitor 230 and the input port of the capacitor module detection circuit 100, thereby improving the measurement accuracy of the capacitor module detection circuit 100 of this application.

[0190] It is worth noting that the above description of the capacitor module detection circuit 100 is intended to clearly illustrate the implementation and verification process of this application. Those skilled in the art can also make equivalent modifications under the guidance of this application; for example, refer to... Figure 20 , Figure 20 The diagram shows another schematic of the capacitor module detection circuit 100 in an embodiment of this application. Those skilled in the art can further add a capacitor Cdummy, another set of integrating capacitors CI connected to the non-inverting input terminal and the inverting output terminal of the first operational amplifier OP1, and an integrating switch SI, thereby modifying the measurement module 120 of this application from a single-ended circuit structure to a fully differential circuit structure.

[0191] Furthermore, this application embodiment also provides a chip, which includes the capacitor module detection circuit 100 described above. A chip (Integrated Circuit, IC) is also called a chip, and this chip can be, but is not limited to, a System-on-Chip (SoC) chip or a System-in-Package (SIP) chip. Since the chip of this application possesses the capacitor module detection circuit 100 described in the above embodiments, it has all the beneficial effects of the capacitor module detection circuit 100 in the above embodiments, and will not be repeated here.

[0192] Furthermore, to better implement the capacitor module detection circuit 100 in the embodiments of this application, based on the chip having the capacitor module detection circuit 100, this application also provides an optical lens movement detection device, see reference. Figure 21 , Figure 21A schematic diagram of an optical lens movement detection device according to an embodiment of this application is shown. The optical lens movement detection device includes: a chip 1000 as described in any of the above embodiments, the chip 1000 having a first output pin TX1, a second output pin TX1, and a first input pin RX; and a capacitor module 200, the capacitor module 200 including a first capacitor 210, a second capacitor 220, and a third capacitor 230, the first electrode 211 of the first capacitor 210, the first electrode 221 of the second capacitor 220, and the first electrode 231 of the third capacitor 230 being electrically connected to each other.

[0193] In this embodiment, the sum of the capacitance values ​​of the first capacitor 210 and the second capacitor 220 does not change with the movement of the optical lens, while the difference between their capacitance values ​​changes with the movement of the optical lens. The first output pin TX1 is connected to the second plate 212 of the first capacitor 210 to control the voltage of the second plate 212. The second output pin TX2 is connected to the second plate 222 of the second capacitor 220 to control the voltage of the second plate 222. The first input pin RX is connected to the second plate 232 of the third capacitor 230 to measure the movement distance of the optical lens based on the amount of charge released from the second plate 232 of the third capacitor 230. This embodiment of the optical lens movement detection device only requires electrical connection to the first capacitor 210, the second capacitor 220, and the second plate 232 of the third capacitor 230, eliminating the need to electrically connect a moving plate and a fixed plate of the same capacitor, thereby reducing the manufacturing difficulty of the optical lens movement detection device.

[0194] Furthermore, to better implement the optical lens movement detection device in the embodiments of this application, this application also provides a focusing motor based on the optical lens movement detection device, the focusing motor including the optical lens movement detection device described in any of the above embodiments. Since the focusing motor in the embodiments of this application has all the beneficial effects of the optical lens movement detection device described in the above embodiments due to the inclusion of the optical lens movement detection device, it will not be described again here.

[0195] Furthermore, to better implement the focusing motor in the embodiments of this application, based on the focusing motor, this application also provides a camera module, which includes the focusing motor as described in any of the above embodiments. Since the camera module in the embodiments of this application is equipped with the optical lens movement detection device of the above embodiments, it possesses all the beneficial effects of the optical lens movement detection device, which will not be elaborated further here.

[0196] Furthermore, to better implement the camera module in the embodiments of this application, based on the camera module, this application also provides an electronic device, which includes the camera module as described in any of the above embodiments. The electronic device may be, but is not limited to, a display, a car center console screen, a car, a smart wearable device, a mobile terminal, or a smart home device. Smart wearable devices include, but are not limited to, smartwatches, smart bracelets, and neck massagers. Mobile terminals include, but are not limited to, smartphones, laptops, tablets, and POS (point of sales terminal) machines. Smart home devices include, but are not limited to, smart sockets, smart rice cookers, smart robot vacuums, and smart lights. Since the electronic device in the embodiments of this application is equipped with the optical lens movement detection device of the above embodiments, it has all the beneficial effects of the optical lens movement detection device, which will not be repeated here.

[0197] 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.

[0198] 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.

[0199] 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.

[0200] 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.

[0201] For each patent, patent application, patent application publication, and other material such as articles, books, specifications, publications, and documents referenced in this application, the entire contents of that patent application are incorporated herein by reference, except for historical application documents that are inconsistent with or conflict with the content of this application, and documents that limit the broadest scope of the claims of this application (currently or subsequently appended to this application). It should be noted that if there are any inconsistencies or conflicts between the descriptions, definitions, and / or terminology used in the supplementary materials of this application and the content of this application, the descriptions, definitions, and / or terminology used in this application shall prevail.

[0202] The foregoing has provided a detailed description of a capacitor module detection circuit, chip, optical lens movement detection device, focusing motor, 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 descriptions of the above embodiments are 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 capacitance module detection circuit, characterized in that: The capacitor module includes a first capacitor, a second capacitor and a third capacitor, the first plate of the first capacitor, the first plate of the second capacitor and the first plate of the third capacitor are electrically connected to each other, and the capacitor module detection circuit includes: A voltage control module, the voltage control module is used to control the voltage of the second plate of the first capacitor and the second plate of the second capacitor; a measuring module, the measuring module being configured to output a first digital signal related to a first capacitance value according to an amount of charge released by the second electrode plate of the third capacitor, and output a second digital signal related to a second capacitance value according to an amount of charge released by the second electrode plate of the third capacitor, during a process in which the voltage control module changes the voltages of the second electrode plate of the first capacitor and the second electrode plate of the second capacitor; The first capacitance value is the difference between the capacitance values ​​of the first capacitance and the second capacitance, the second capacitance value is the sum of the capacitance values ​​of the first capacitance and the second capacitance, and the difference between the capacitance values ​​of the first capacitance and the second capacitance changes with the movement of the detection object; The sum of the capacitance values ​​of the first capacitor and the second capacitor does not change with the movement of the detection object, or the series capacitance value of the first capacitor and the second capacitor does not change with the movement of the detection object.

2. The capacitor module detection circuit according to claim 1, characterized in that: In the process in which the measuring module outputs a first digital signal related to the first capacitance value according to the amount of charge released by the second electrode plate of the third capacitor, the voltage changes of the second electrode plate of the first capacitor and the second electrode plate of the second capacitor are opposite; When the measuring module outputs a second digital signal related to the second capacitance value according to the amount of charge released by the second plate of the third capacitor, the voltage changes of the second plate of the first capacitor and the second plate of the second capacitor are the same.

3. The capacitor module detection circuit according to claim 2, characterized in that: The voltage control module has a first working state, a second working state, a third working state and a fourth working state; The measuring module outputs the first digital signal related to the first capacitance value according to the amount of charge released by the second electrode plate of the third capacitor when the voltage control module switches from the first working state to the second working state; The measuring module outputs the second digital signal related to the second capacitance value according to the amount of charge released by the second electrode plate of the third capacitor when the voltage control module switches from the third working state to the fourth working state; Wherein, in the first working state, the voltage control module controls the voltage of the second plate of the first capacitor to be a first reference voltage, and controls the voltage of the second plate of the second capacitor to be a second reference voltage, and the first reference voltage is not equal to the second reference voltage; In the second working state, the voltage control module controls the voltage of the second plate of the first capacitor to be the second reference voltage, and controls the voltage of the second plate of the second capacitor to be the first reference voltage; In the third working state, the voltage control module controls the voltage of the second plate of the first capacitor to be the first reference voltage, and controls the voltage of the second plate of the second capacitor to be the first reference voltage; In the fourth working state, the voltage control module controls the voltage of the second plate of the first capacitor to be the second reference voltage, and controls the voltage of the second plate of the second capacitor to be the second reference voltage.

4. The capacitor module detection circuit according to claim 3, characterized in that: The voltage control module includes a first switch, a second switch, a third switch and a fourth switch; A first end of the first switch is connected to the first reference voltage, and a second end of the first switch is connected to the second plate of the first capacitor; A first end of the second switch is connected to the second reference voltage, and a second end of the second switch is connected to the second plate of the first capacitor; A first end of the third switch is connected to the first reference voltage, and a second end of the third switch is connected to the second plate of the second capacitor; A first end of the fourth switch is connected to the second reference voltage, and a second end of the fourth switch is connected to the second plate of the second capacitor.

5. The capacitor module detection circuit according to claim 3, characterized in that: The voltage control module includes a first clock output unit and a second clock output unit; The first clock output unit is used to output a first clock signal whose high level is the first reference voltage and whose low level is the second reference voltage; The second clock output unit is used to output a second clock signal whose high level is the first reference voltage and whose low level is the second reference voltage; The first clock signal and the second clock signal are in opposite phases.

6. The capacitor module detection circuit according to claim 1, characterized in that: The measuring module includes a first operational amplifier and an integrating capacitor; The inverting input terminal of the first operational amplifier is connected to the second plate of the third capacitor, and the non-inverting input terminal of the first operational amplifier is connected to the ground terminal; The first plate of the integrating capacitor is connected to the inverting input terminal of the first operational amplifier, and the second plate of the integrating capacitor is connected to the output terminal of the first operational amplifier.

7. The capacitor module detection circuit according to claim 6, characterized in that: The measurement module also includes an integration switch and an analog-to-digital converter; The first end of the integration switch is connected to the inverting input end of the first operational amplifier, and the second end of the integration switch is connected to the output end of the first operational amplifier; The input end of the analog-to-digital converter is connected to the output end of the first operational amplifier, and the analog-to-digital converter is used to output the first digital signal and the second digital signal.

8. The capacitor module detection circuit according to claim 6, characterized in that: The measurement module also includes a feedback resistor, a demodulation unit and an analog-to-digital converter; The first end of the feedback resistor is connected to the inverting input end of the first operational amplifier, and the second end of the feedback resistor is connected to the output end of the first operational amplifier; The demodulation unit is used to demodulate the continuous voltage signal output by the first operational amplifier into a discrete signal, and the analog-to-digital converter is used to output the first digital signal and the second digital signal according to the discrete signal.

9. The capacitor module detection circuit according to claim 6, characterized in that: The measurement module also includes a first integrating switch, a second integrating switch, a quantizer, and a digital-to-analog converter; A first terminal of the first integration switch is connected to an inverting input terminal of the first operational amplifier, and a second terminal of the first integration switch is connected to an output terminal of the first operational amplifier; A first end of the second integration switch is connected to the inverting input end of the first operational amplifier, and a second end of the second integration switch is connected to the first plate of the integration capacitor; The quantizer is connected to the output end of the first operational amplifier, the input end of the digital-to-analog converter is connected to the output end of the quantizer, and the output end of the digital-to-analog converter is connected to the inverting input end of the first operational amplifier.

10. The capacitor module detection circuit according to claim 6, characterized in that: The measurement module also includes a demodulation unit, a quantizer and a digital-to-analog converter; The input end of the demodulation unit is connected to the second plate of the third capacitor, the output end of the demodulation unit is connected to the inverting input end of the first operational amplifier, and the demodulation unit is used to demodulate the continuous charge signal output by the second plate of the third capacitor into a discrete signal; The quantizer is connected to the output end of the first operational amplifier, the input end of the digital-to-analog converter is connected to the output end of the quantizer, and the output end of the digital-to-analog converter is connected to the inverting input end of the first operational amplifier.

11. The capacitor module detection circuit according to claim 10, characterized in that: The measurement module also includes a current mirror; The input end of the current mirror is connected to the second plate of the third capacitor, and the output end of the current mirror is connected to the input end of the demodulation unit.

12. A chip, characterized in that: It comprises a capacitance module detection circuit as described in any one of claims 1 to 11.

13. An optical lens movement detection device, characterized in that: include: The chip as claimed in claim 12, wherein the chip has a first output pin, a second output pin and a first input pin; A capacitor module, the capacitor module comprising a first capacitor, a second capacitor and a third capacitor, wherein a first plate of the first capacitor, a first plate of the second capacitor and a first plate of the third capacitor are electrically connected to each other; wherein the difference between the capacitance values ​​of the first capacitor and the second capacitor changes with the movement of the optical lens; The sum of the capacitance values ​​of the first capacitor and the second capacitor does not change with the movement of the detection object, or the series capacitance value of the first capacitor and the second capacitor does not change with the movement of the detection object; The first output pin is connected to the second plate of the first capacitor to control the voltage of the second plate of the first capacitor, the second output pin is connected to the second plate of the second capacitor to control the voltage of the second plate of the second capacitor, and the first input pin is connected to the second plate of the third capacitor to measure the moving distance of the optical lens according to the amount of charge released by the second plate of the third capacitor.

14. A focus motor, characterized in that: Comprising the optical lens movement detection device as described in claim 13.

15. A camera module, characterized in that: Comprising the focus motor as claimed in claim 14.

16. An electronic device, characterized in that: Including the camera module as described in claim 15.

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