System for driving an actuator

Abstract

The present invention relates to a system for driving an actuator. The system for driving an actuator capable of providing constant resolution regardless of the type of the actuator according to an aspect of the present invention includes an actuator driving circuit configured to generate a driving current for operating the actuator and output the generated driving current to operate the actuator, a current sensing unit configured to sense a current operating the actuator and generate a first sensing signal, and a gain adjusting unit configured to calculate a gain based on a first maximum driving current range of the operating actuator and a second maximum driving current range of a reference actuator and change the first sensing signal to a second sensing signal based on the gain. A signal generated based on the second sensing signal is input to the actuator driving circuit.

Description

Technical Field

[0001] This disclosure relates to a system for driving an actuator, and more specifically, to a system for driving an actuator capable of compensating for jitter. Background Technology

[0002] Electronic devices embedded in a camera module may include an optical image stabilizer (OIS) to prevent camera shake. OIS detects shake and moves the lens embedded in the camera module to prevent image shake due to the shake.

[0003] OIS uses actuators to move the lens, and the range of currents required to move the lens the same distance can vary depending on the actuator. Therefore, the resolution of OIS can vary depending on the actuator, and a decrease in resolution can result in a decrease in system performance. Summary of the Invention

[0004] This disclosure is designed to solve the above-mentioned problems and aims to provide a system for driving actuators that can provide constant resolution regardless of the type of actuator.

[0005] One aspect of this disclosure provides a system for driving an actuator, the system comprising: an actuator driving circuit configured to generate a drive current for operating the actuator and output the generated drive current to the operating actuator; a current sensing unit configured to sense the current of the operating actuator and generate a sensing signal; and a gain adjustment unit configured to calculate a gain based on a first maximum drive current range of the operating actuator and a second maximum drive current range of a reference actuator and to change the sensing signal based on the gain. A signal generated based on the second sensing signal is input to the actuator driving circuit.

[0006] Another aspect of this disclosure provides a system for driving an actuator, the system comprising: a jitter detector configured to detect jitter and generate a detection signal; a controller configured to generate a control signal based on the detection signal for moving the actuator to a target position; and a driver configured to adjust a drive current according to the control signal in accordance with a first step drive current and move the actuator to the target position. The driver changes the first step drive current according to a first maximum drive current range of the actuator. Attached Figure Description

[0007] The accompanying drawings are included to provide a further understanding of this disclosure and are incorporated in and constitute a part of this application. The drawings illustrate embodiments of the disclosure and, together with the description, serve to illustrate the principles of the disclosure. In the drawings:

[0008] Figure 1 This is a block diagram illustrating a system for driving an actuator according to an embodiment of the present disclosure;

[0009] Figures 2A to 2C This is a diagram illustrating an example of operation in a system for driving an actuator, excluding a gain adjustment unit;

[0010] Figure 3 It is a graph showing the number of steps and the step drive current according to the type of actuator in a system for driving actuators without a gain adjustment unit;

[0011] Figure 4A and Figure 4B This is a diagram illustrating an example of operation in a system for driving an actuator, including a gain adjustment unit; and

[0012] Figure 5 This is a graph showing the number of steps and the step drive current in a system for driving actuators, including a gain adjustment unit, according to the type of actuator. Detailed Implementation

[0013] Exemplary embodiments of this disclosure will now be described in detail, examples of which are illustrated in the accompanying drawings. Where possible, the same reference numerals will be used throughout the drawings to denote the same or similar parts.

[0014] When using the terms "including," "having," and "comprising" as described in this specification, an additional part may be added unless "only" is used. Unless otherwise stated, singular terms may include plural forms.

[0015] It will be understood that although the terms “first,” “second,” etc., are used herein to describe various elements, these elements should not be limited by these terms. These terms are used only to distinguish one element from another. For example, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element, without departing from the scope of this disclosure.

[0016] The term "at least one" should be understood to include any and all combinations of one or more of the associated listed items. For example, in addition to the first, second, or third item, "at least one of the first, second, and third items" means a combination of all items derived from two or more of the first, second, and third items.

[0017] Features of the various embodiments of this disclosure may be partially or wholly linked or combined with each other, and may be interoperable and technically driven in different ways. Embodiments of this disclosure may be implemented independently of each other, or may be implemented together in an interdependent manner.

[0018] Hereinafter, exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0019] Figure 1 This is a block diagram illustrating a system for driving an actuator according to an embodiment of the present disclosure.

[0020] The system 100 for driving an actuator according to an embodiment of the present disclosure can be disposed in an electronic device in which a camera module is embedded. In this case, the system 100 for driving the actuator can be embedded inside the camera module or inside an electronic device (e.g., a smartphone) in which a camera module is installed.

[0021] like Figure 1 As shown, a system 100 for driving an actuator according to an embodiment of the present disclosure includes a jitter detector 110, a controller 120, a driver 130, and an actuator 140.

[0022] Actuator 140 can move the lens of the camera module based on the drive current output from driver 130. Specifically, actuator 140 can determine the movement distance of the lens based on the amount of drive current applied from driver 130, and move the lens of the camera module in a predetermined movement direction according to the determined movement distance.

[0023] In one embodiment, actuator 140 may include a voice coil motor (VCM). The VCM can move the lens of the camera module by utilizing the principle that a force is generated when an electric current flows through a coil in a magnetic field formed by a magnet.

[0024] Shake detector 110 detects shake of the camera module (not shown) or the electronic device on which the camera module is mounted and generates a detection signal. In an embodiment, shake detector 110 may be a gyroscope sensor. A gyroscope sensor is a motion sensor that detects shake of the camera module and can detect shake of the camera module and output angular velocity.

[0025] The controller 120 generates a control signal for controlling the actuator 140 so that the jitter detected by the jitter detector 110 is canceled out. Specifically, the controller 120 may detect the position of the actuator 140 or a lens (not shown). The controller 120 may determine a target position for the actuator 140, which is used to move the lens (not shown) of the camera module in the opposite direction of the jitter, based on the detected position. The controller 120 may generate a control signal for moving the actuator 140 to the target position. In this case, the controller 120 may generate a digital control signal.

[0026] The driver 130 adjusts the drive current and moves the actuator 140 to a target position based on the control signal input from the controller 120. Specifically, the moving distance of the actuator 140 can be determined based on the drive current applied from the driver 130. The controller 120 can calculate the moving distance required for the actuator 140 to move to the target position. In addition, the controller 120 can generate a control signal to allow the drive current corresponding to the calculated moving distance to be applied to the actuator 140, and can output the control signal to the driver 130.

[0027] When a control signal is applied from the controller 120, the driver 130 can output a drive current corresponding to the control signal to the actuator 140. In this case, the driver 130 can change the drive current in step increments. The driver 130 can output a drive current corresponding to the control signal to the actuator 140 while simultaneously increasing or decreasing the drive current by a step. Here, the step drive current can represent the size of the range of drive currents included in a step.

[0028] In the driver 130 according to an embodiment of the present disclosure, the step drive current can be varied according to the maximum drive current range of the actuator 140, so that the step number (or resolution) is maintained constant regardless of the type of actuator 140.

[0029] More specifically, the driver 130 according to an embodiment of the present disclosure may determine the first step drive current of the operating actuator 140 based on a first maximum drive current range of the operating actuator 140, a second maximum drive current range of the reference actuator, and a second step drive current of the reference actuator.

[0030] Here, the actuator 140 corresponds to the actuator installed in the actual electronic device to move the lens of the camera module. The first maximum drive current range corresponds to the maximum drive current range of the actuator installed in the actual electronic device, and the first step drive current corresponds to the step drive current of the actuator installed in the actual electronic device.

[0031] Furthermore, the reference actuator corresponds to an actuator that is not actually installed in the electronic device but is used as a reference for determining the step drive current of various types of actuators. The second maximum drive current range is the maximum drive current range of the reference actuator and may have a preset value. Similar to the second maximum drive current range, the second step drive current is the step drive current of the reference actuator and may have a preset value.

[0032] In an implementation, the first step drive current of the operating actuator 140 may correspond to a value obtained by multiplying the second step drive current by the ratio of the first maximum drive current range of the operating actuator 140 to the second maximum drive current range of the reference actuator.

[0033] For example, suppose the second maximum drive current range of the reference actuator is 10mA, the second step drive current is 1mA, and the first maximum drive current range of the operating actuator 140 is 5mA. In this case, the first step drive current of the operating actuator 140 can correspond to the value obtained by multiplying 1mA (the second step drive current) by 0.5 (the ratio of the first maximum drive current range of the operating actuator 140 to the second maximum drive current range of the reference actuator (5mA / 10mA)). That is, the first step drive current of the operating actuator 140 can be 0.5mA.

[0034] Therefore, despite the different maximum drive current ranges, the reference actuator and the operating actuator 140 can have the same resolution. Specifically, since the reference actuator has a second step drive current of 1mA, the reference actuator can have ten steps up to 10mA (the second maximum drive current range). Since the operating actuator 140 has a first step drive current of 0.5mA, the operating actuator 140 can also have ten steps up to 5mA (the first maximum drive current range).

[0035] As described above, regardless of the type of actuator, the driver 130 according to the embodiments of this disclosure has the same step number, and therefore no resolution degradation occurs.

[0036] In order to have the same step number regardless of the type of actuator as described above, the driver 130 includes a digital-to-analog converter 131, an error amplifier 132, an actuator drive circuit 133, a current sensing unit 134, and a gain adjustment unit 135.

[0037] The digital-to-analog converter 131 converts the digital control signal used to move the actuator 140 to the target position into an analog control signal. Specifically, the digital-to-analog converter 131 can receive the digital control signal used to move the actuator 140 to the target position from the controller 120.

[0038] The digital-to-analog converter 131 can convert digital control signals into analog voltages and output the converted analog voltages. In this case, the digital-to-analog converter 131 can output an analog voltage while increasing the analog voltage by a voltage value corresponding to the step current. Here, the step current of the digital-to-analog converter 131 can be the same as the second step drive current of the reference actuator.

[0039] For example, when the second step drive current of the reference actuator is 1mA, the step current of the digital-to-analog converter 131 can also be 1mA. The digital-to-analog converter 131 can increase the analog voltage by a voltage value corresponding to 1mA.

[0040] The current sensing unit 134 senses the current of the operating actuator 140. In one embodiment, the current sensing unit 134 may sense the current flowing through a coil included in the operating actuator 140. In another embodiment, the current sensing unit 134 may sense the current output from the actuator drive circuit 133.

[0041] In addition, the current sensing unit 134 can generate a first sensing signal by converting the sensed current into a voltage.

[0042] The gain adjustment unit 135 calculates the gain based on a first maximum drive current range of the operating actuator 140 and a second maximum drive current range of the reference actuator, and converts the first sensing signal into a second sensing signal based on the calculated gain. Here, the first sensing signal may correspond to the value sensed by the current sensing unit 134, and the second sensing signal may correspond to the value obtained by reflecting the gain onto the first sensing signal.

[0043] Specifically, the gain adjustment unit 135 can calculate the ratio of the second maximum drive current range of the reference actuator to the first maximum drive current range of the operating actuator 140 as the gain. The gain adjustment unit 135 can multiply the first sensing signal generated by the current sensing unit 134 by the calculated gain to convert the first sensing signal into a second sensing signal.

[0044] For example, suppose the second maximum drive current range of the reference actuator is 10mA and the first maximum drive current range of the operating actuator 140 is 5mA. In this case, the gain adjustment unit 135 can calculate the gain as 2 (the ratio of the second maximum drive current range of the reference actuator to the first maximum drive current range of the operating actuator 140 (10mA / 5mA)). The gain adjustment unit 135 can multiply the first sensing signal generated by the current sensing unit 134 by 2 to convert the first sensing signal into a second sensing signal. The gain adjustment unit 135 can output the second sensing signal.

[0045] Error amplifier 132 can amplify the error between the second sensing signal output from gain adjustment unit 135 and the analog control signal output from digital-to-analog converter 131.

[0046] Specifically, when the second sensing signal output from the gain adjustment unit 135 is different from the analog control signal output from the digital-to-analog converter 131, the error amplifier 132 can amplify the error between the two signals and supply the actuator drive circuit 133 with the voltage required to make the two signals the same.

[0047] In one implementation, the error amplifier 132 calculates the error ratio between the analog control signal output from the digital-to-analog converter 131 and the second sensing signal output from the gain adjustment unit 135, multiplies the analog control signal by the reciprocal of the error ratio, and outputs the value obtained through multiplication. In this case, the error ratio can be calculated as the ratio of the second sensing signal to the analog control signal.

[0048] The actuator drive circuit 133 generates a drive current for operating the actuator 140 based on the signal output from the error amplifier 132. The actuator drive circuit 133 outputs the drive current to operate the actuator 140.

[0049] In a system 100 for driving an actuator according to an embodiment of the present disclosure, the step drive current of the actuator drive circuit 133 may be different from the step current of the digital-to-analog converter 131.

[0050] Specifically, the step current of the digital-to-analog converter 131 can be the same as the step drive current of the reference actuator. On the other hand, the step drive current of the actuator drive circuit 133 is the step drive current of the operating actuator 140 and can have a different value than the step current of the digital-to-analog converter 131, because the signal output from the digital-to-analog converter 131 changes based on the gain adjustment unit 135 reflecting the gain signal.

[0051] Figures 2A to 2C This is a diagram illustrating an example of operation in a system for driving an actuator, excluding a gain adjustment unit. Figure 3 This is a graph showing the number of steps and the step drive current according to the type of actuator in a system for driving actuators without a gain adjustment unit.

[0052] Although the signals output from the digital-to-analog converter 131, the error amplifier 132, and the current sensing unit 134 correspond to voltages, for ease of description, current values ​​will be used as a reference below.

[0053] Figure 2A An example of operation in a system 100 for driving an actuator is shown when an error occurs between the signal output from the digital-to-analog converter 131 and the signal output from the current sensing unit 134.

[0054] For example, the digital-to-analog converter 131 can output a signal corresponding to 5mA. When there is no signal output from the current sensing unit 134 or when the signal output from the current sensing unit 134 is equal to 5mA, the error amplifier 132 can output a signal corresponding to 5mA. Therefore, the actuator drive circuit 133 can output 5mA to the actuator 140. The current sensing unit 134 can sense the current of the actuator 140, and the sensed current of the actuator 140 can be 4mA, such as... Figure 2A As shown.

[0055] Error amplifier 132 amplifies the error between the signal output from digital-to-analog converter 131 and the signal output from current sensing unit 134. Specifically, the signal output from digital-to-analog converter 131 may correspond to 5mA, and the signal output from current sensing unit 134 may correspond to 4mA. In this case, error amplifier 132 can calculate the error ratio between the signal output from digital-to-analog converter 131 and the signal output from current sensing unit 134, so that the output of current sensing unit 134 becomes 5mA, and error amplifier 132 can multiply the signal output from digital-to-analog converter 131 by the reciprocal of the error ratio.

[0056] Error amplifier 132 can calculate the error ratio as 4 / 5, which is the ratio of the 4mA output of current sensing unit 134 to the 5mA output of digital-to-analog converter 131. Error amplifier 132 can multiply the 5mA output of digital-to-analog converter 131 by the reciprocal of the error ratio, 5 / 4. Therefore, error amplifier 132 can output 6.25mA to actuator drive circuit 133.

[0057] The actuator drive circuit 133 can output 5mA. The current sensing unit 134 can sense the current of the actuator 140, and the sensed current of the actuator 140 can be 5mA. As a result, in the system 100 for driving the actuator, the signal output from the digital-to-analog converter 131 can be made the same as the signal output from the current sensing unit 134 by the error amplifier 132.

[0058] Figure 2B and Figure 2C An example of operation in a system 100 for driving an actuator is shown when there is no error between the signal output from the digital-to-analog converter 131 and the signal output from the current sensing unit 134.

[0059] As an example, the digital-to-analog converter 131 can output a signal corresponding to 5mA, such as Figure 2B As shown. When the signal output from the current sensing unit 134 is equal to 5mA, the error amplifier 132 can output a signal corresponding to 5mA. Therefore, the actuator drive circuit 133 can output 5mA to the actuator 140. The current sensing unit 134 can sense the current of the actuator 140, and the sensed current of the actuator 140 can be 5mA, such as... Figure 2B As shown.

[0060] As another example, the digital-to-analog converter 131 can output a signal corresponding to 10mA, such as Figure 2CAs shown. When the signal output from the current sensing unit 134 is equal to 10mA, the error amplifier 132 can output a signal corresponding to 10mA. Therefore, the actuator drive circuit 133 can output 10mA to the actuator 140. The current sensing unit 134 can sense the current of the actuator 140, and the sensed current of the actuator 140 can be 10mA, such as... Figure 2C As shown.

[0061] like Figure 2B and Figure 2C As shown, in the system 100 for driving the actuator, excluding the gain adjustment unit 135, when there is no error between the signal output from the digital-to-analog converter 131 and the signal output from the current sensing unit 134, the value output from the digital-to-analog converter 131 is equal to the value output from the actuator drive circuit 133. That is, the step current of the digital-to-analog converter 131 is the same as the step drive current of the actuator drive circuit 133.

[0062] As a result, in the system 100 for driving the actuator, excluding the gain adjustment unit 135, the same step drive currents S1 and S2 can be provided regardless of the type of actuator 140, such as Figure 3 As shown.

[0063] More specifically, the maximum drive current range of the first actuator 1 may differ from the maximum drive current range of the second actuator 2. The first actuator 1 may have a maximum drive current range of 10mA, and the second actuator 2 may have a maximum drive current range of less than 5mA, which is less than that of the first actuator 1.

[0064] Furthermore, the step current S3 of the digital-to-analog converter 131 can be 1mA, such as Figure 3 As shown.

[0065] In the system 100 for driving the actuator without the gain adjustment unit 135, the step current S3 of the digital-to-analog converter 131 is the same as the step drive current of the actuator 140, so the step drive current S1 of the first actuator 1 can also be 1mA. Since the maximum drive current range of the first actuator 1 is 10mA, the system 100 for driving the actuator without the gain adjustment unit 135 can drive and control the first actuator 1 in ten steps.

[0066] Furthermore, in the system 100 for driving the actuator without the gain adjustment unit 135, the step current S3 of the digital-to-analog converter 131 is the same as the step drive current of the actuator 140, so the step drive current S2 of the second actuator 2 can also be 1mA. Since the maximum drive current range of the second actuator 2 is 5mA, the system 100 for driving the actuator without the gain adjustment unit 135 can drive and control the second actuator 2 in five steps. That is, since the second actuator 2 has a smaller maximum drive current range than the first actuator 1, the number of steps (i.e., resolution) can be reduced. Therefore, the performance of the system 100 for driving the actuator may be degraded.

[0067] Figure 4A and Figure 4B This is a diagram illustrating an example of operation in a system for driving an actuator, including a gain adjustment unit. Figure 5 This is a graph showing the number of steps and the step drive current in a system for driving actuators, including a gain adjustment unit, according to the type of actuator.

[0068] Although the signals output from the digital-to-analog converter 131, error amplifier 132, current sensing unit 134 and gain adjustment unit 135 correspond to voltages, for ease of description, current values ​​will be used as a reference below.

[0069] Furthermore, for ease of description, it is assumed that the reference actuator has a maximum drive current range of 10mA and the operating actuator 140 has a maximum drive current range of less than 5mA of the reference actuator.

[0070] Figure 4A An example of operation is shown in a system 100 for driving an actuator, including a gain adjustment unit 135, when the digital-to-analog converter 131 outputs a signal corresponding to 5mA.

[0071] The digital-to-analog converter 131 can output a signal corresponding to 5mA. When there is no signal output from the gain adjustment unit 135 or when the signal output from the digital-to-analog converter 131 is equal to 5mA, the error amplifier 132 can output a signal corresponding to 5mA. Therefore, the actuator drive circuit 133 can output 5mA to the actuator 140. The current sensing unit 134 can sense the current of the actuator 140, and the sensed current of the actuator 140 can be 5mA, such as... Figure 4A As shown.

[0072] The gain adjustment unit 135 can multiply 5mA (the output of the current sensing unit 134) by a gain. Specifically, the gain adjustment unit 135 can calculate the gain as 2, which is the ratio of the second maximum drive current range of the reference actuator to the first maximum drive current range of the operating actuator 140 (10mA / 5mA). The gain adjustment unit 135 can output 10mA, obtained by multiplying 5mA (the output of the current sensing unit 134) by 2.

[0073] Error amplifier 132 amplifies the error between the signal output from digital-to-analog converter 131 and the signal output from gain adjustment unit 135. Specifically, the signal output from digital-to-analog converter 131 may correspond to 5mA, and the signal output from gain adjustment unit 135 may correspond to 10mA. In this case, error amplifier 132 can calculate the error ratio between the signal output from digital-to-analog converter 131 and the signal output from gain adjustment unit 135, so that the output of gain adjustment unit 135 becomes 5mA, and error amplifier 132 can multiply the signal output from digital-to-analog converter 131 by the reciprocal of the error ratio.

[0074] Error amplifier 132 can calculate the error ratio as 10 / 5, which is the ratio of the 10mA output of gain adjustment unit 135 to the 5mA output of digital-to-analog converter 131. Error amplifier 132 can multiply the 5mA output of digital-to-analog converter 131 by the reciprocal of the error ratio, 5 / 10. Therefore, error amplifier 132 can output 2.5mA to actuator drive circuit 133.

[0075] The actuator drive circuit 133 can output 2.5mA. The current sensing unit 134 can sense the current of the actuator 140, and the sensed current of the actuator 140 can be 2.5mA. The gain adjustment unit 135 can multiply the output 2.5mA of the current sensing unit 134 by a gain. Specifically, the gain adjustment unit 135 can calculate the gain as 2, which is the ratio of the second maximum drive current range of the reference actuator to the first maximum drive current range of the actuator 140 (10mA / 5mA). The gain adjustment unit 135 can output 5mA, obtained by multiplying the output 2.5mA of the current sensing unit 134 by 2.

[0076] As a result, in the system 100 used to drive the actuator, the signal output from the digital-to-analog converter 131 can be made the same as the signal output from the gain adjustment unit 135 by the error amplifier 132.

[0077] Figure 4B An example of operation is shown in a system 100 for driving an actuator, including a gain adjustment unit 135, when the digital-to-analog converter 131 outputs a signal corresponding to 10mA.

[0078] The digital-to-analog converter 131 can output a signal corresponding to 10mA. When there is no output signal from the gain adjustment unit 135 or when the signal output from the digital-to-analog converter 131 is equal to 10mA, the error amplifier 132 can output a signal corresponding to 10mA. Therefore, the actuator drive circuit 133 can output 10mA to the actuator 140. The current sensing unit 134 can sense the current operating the actuator 140, and the sensed current operating the actuator 140 can be 10mA, such as... Figure 4B As shown.

[0079] The gain adjustment unit 135 can multiply 10mA (the output of the current sensing unit 134) by the gain. Specifically, the gain adjustment unit 135 can calculate the gain as 2, which is the ratio of the second maximum drive current range of the reference actuator to the first maximum drive current range of the operating actuator 140 (10mA / 5mA). The gain adjustment unit 135 can output 20mA, obtained by multiplying 10mA (the output of the current sensing unit 134) by 2.

[0080] Error amplifier 132 amplifies the error between the signal output from digital-to-analog converter 131 and the signal output from gain adjustment unit 135. Specifically, the signal output from digital-to-analog converter 131 may correspond to 10mA, and the signal output from gain adjustment unit 135 may correspond to 20mA. In this case, error amplifier 132 calculates the error ratio between the signal output from digital-to-analog converter 131 and the signal output from gain adjustment unit 135, such that the output of gain adjustment unit 135 becomes 5mA, and error amplifier 132 can multiply the signal output from digital-to-analog converter 131 by the reciprocal of the error ratio.

[0081] Error amplifier 132 can calculate the error ratio as 20 / 10, which is the ratio of the output 20mA of gain adjustment unit 135 to the output 10mA of digital-to-analog converter 131. Error amplifier 132 can multiply 10mA (output of digital-to-analog converter 131) by 10 / 20 (the reciprocal of the error ratio). Therefore, error amplifier 132 can output 5mA to actuator drive circuit 133.

[0082] The actuator drive circuit 133 can output 5mA. The current sensing unit 134 can sense the current operating the actuator 140, and the sensed current operating the actuator 140 can be 5mA. The gain adjustment unit 135 can multiply the output 5mA of the current sensing unit 134 by a gain. Specifically, the gain adjustment unit 135 can calculate the gain as 2, which is the ratio of the second maximum drive current range of the reference actuator to the first maximum drive current range of the operating actuator 140 (10mA / 5mA). The gain adjustment unit 135 can output 10mA obtained by multiplying 5mA (the output of the current sensing unit 134) by 2.

[0083] As a result, in the system 100 used to drive the actuator, the signal output from the digital-to-analog converter 131 can be made the same as the signal output from the gain adjustment unit 135 by the error amplifier 132.

[0084] like Figure 4A and Figure 4B As shown, in the system 100 for driving an actuator, which includes a gain adjustment unit 135, the value output from the digital-to-analog converter 131 may differ from the value output from the actuator drive circuit 133. That is, the step current of the digital-to-analog converter 131 may differ from the step drive current of the actuator drive circuit 133.

[0085] As a result, in the system 100 for driving the actuator, including the gain adjustment unit 135, a constant step number, i.e., constant resolution, can be provided regardless of the type of actuator 140 being operated. Figure 5 As shown.

[0086] More specifically, the maximum drive current range of the first actuator 1 may differ from the maximum drive current range of the second actuator 2. The first actuator 1 may have a maximum drive current range of 10mA, and the second actuator 2 may have a maximum drive current range of 5mA smaller than that of the first actuator 1.

[0087] Furthermore, the step current S3 of the digital-to-analog converter 131 can be 1mA, such as Figure 5 As shown.

[0088] In the system 100 for driving actuators, including a gain adjustment unit 135, the step current S3 of the digital-to-analog converter 131 can be the same as the step drive current S1 of the first actuator 1. When the maximum drive current range of the first actuator 1 is the same as the maximum drive current range of the reference actuator, the gain adjustment unit 135 can calculate the gain as 1, which is the ratio of the maximum drive current range of the reference actuator to the maximum drive current range of the first actuator 1 (10mA / 10mA). The gain adjustment unit 135 can multiply the signal output from the current sensing unit 134 by 1 and output the value obtained by multiplication. When no other errors occur, the error amplifier 132 outputs the signal from the digital-to-analog converter 131 to the actuator drive circuit 133.

[0089] As a result, the step drive current S1 of the first actuator 1 can be the same as the step current S3 of the digital-to-analog converter 131, such as Figure 5As shown. Since the maximum drive current range of the first actuator 1 is 10mA, the system 100 for driving the actuator, including the gain adjustment unit 135, can drive and control the first actuator 1 in ten steps.

[0090] Furthermore, in the system 100 for driving actuators, including the gain adjustment unit 135, the step current S3 of the digital-to-analog converter 131 may differ from the step drive current S2 of the second actuator 2. When the maximum drive current range of the second actuator 2 differs from the maximum drive current range of the reference actuator, the gain adjustment unit 135 can calculate the gain as 2, which is the ratio of the maximum drive current range of the reference actuator to the maximum drive current range of the second actuator 2 (10mA / 5mA). The gain adjustment unit 135 can multiply the signal output from the current sensing unit 134 by 2 and output the value obtained through multiplication.

[0091] Error amplifier 132 calculates the error ratio between the signal output from digital-to-analog converter 131 and the signal output from gain adjustment unit 135. Typically, when no other errors occur, the signal output from gain adjustment unit 135 is doubled as the signal output from digital-to-analog converter 131. Therefore, error amplifier 132 can calculate the error ratio between the signal output from digital-to-analog converter 131 and the signal output from gain adjustment unit 135 to be 2. Error amplifier 132 multiplies the signal output from digital-to-analog converter 131 by 1 / 2 (the reciprocal of the error ratio) and outputs the value obtained through multiplication to actuator drive circuit 133.

[0092] As a result, the step drive current S2 of the second actuator 2 can be 0.5mA, which is half of the step current S3 of the digital-to-analog converter 131. Figure 5 As shown. Since the maximum drive current range of the second actuator 2 is 5mA, the system 100 for driving the actuator, including the gain adjustment unit 135, can drive and control the second actuator 2 in ten steps.

[0093] In the system 100 for driving actuators, including the gain adjustment unit 135, the step number (i.e., resolution) remains constant even when the maximum drive current range of the second actuator 2 is less than the maximum drive current range of the first actuator 1. Therefore, in the system 100 for driving actuators, including the gain adjustment unit 135, constant resolution is provided regardless of the type of actuator 140, and performance degradation due to resolution degradation is prevented.

[0094] According to this disclosure, the resolution will not decrease even when the maximum drive current range of the actuator decreases. Therefore, in this disclosure, system performance degradation due to resolution degradation can be prevented.

[0095] Furthermore, this disclosure provides constant resolution regardless of the type of actuator, thus making it compatible with various types of actuators with different maximum drive current ranges. Therefore, the actuator can be freely and easily modified in this disclosure.

[0096] Furthermore, the methods described in this specification may be implemented, at least in part, using one or more computer programs or components. Components may be provided as a series of computer instructions on a computer-readable or machine-readable medium, including volatile and non-volatile memory. Instructions may be provided as software or firmware and may be implemented, wholly or partially, in a hardware configuration such as an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), a digital signal processor (DSP), or other similar device. Instructions may be configured to be executed by one or more processors or other hardware components, and these processors or other hardware configurations, when executing the series of computer instructions, perform, or enable to perform, all or part of the methods and procedures disclosed in this specification.

Claims

1. A system for driving an actuator, the system comprising: An actuator drive circuit is configured to generate a drive current for operating the actuator and output the generated drive current to the operating actuator. A current sensing unit configured to sense the current of the operating actuator and generate a first sensing signal; as well as A gain adjustment unit is configured to calculate a gain based on a first maximum drive current range of the operating actuator and a second maximum drive current range of a reference actuator, and to convert the first sensing signal into a second sensing signal based on the gain. The signal generated based on the second sensing signal is input to the actuator drive circuit. The gain adjustment unit calculates the ratio of the second maximum drive current range to the first maximum drive current range as the gain, and The gain adjustment unit multiplies the first sensing signal by the gain to convert the first sensing signal into the second sensing signal.

2. The system for driving an actuator according to claim 1, further comprising: A digital-to-analog converter configured to convert digital control signals used to move the actuator to a target position into analog control signals and output the converted analog control signals; as well as An error amplifier configured to amplify the error between the second sensing signal output from the gain adjustment unit and the analog control signal output from the digital-to-analog converter.

3. The system for driving an actuator according to claim 2, wherein, The error amplifier calculates the error ratio between the analog control signal and the second sensing signal and multiplies the analog control signal by the reciprocal of the error ratio.

4. The system for driving an actuator according to claim 3, wherein, The error amplifier calculates the ratio of the second sensing signal to the analog control signal as the error ratio.

5. The system for driving an actuator according to claim 2, wherein, The step drive current of the actuator drive circuit is different from the step current of the digital-to-analog converter.

6. The system for driving an actuator according to claim 5, wherein, The step drive current of the actuator drive circuit corresponds to the ratio of the step current of the digital-to-analog converter to the gain.

7. The system for driving an actuator according to claim 1, wherein, The operating actuator has the same resolution as the reference actuator.

8. A system for driving an actuator, the system comprising: A jitter detector, configured to detect jitter and generate a detection signal; A controller configured to generate a control signal based on the detected signal for moving the actuator to a target position; as well as A driver configured to adjust the drive current according to the control signal by a first step drive current and move the actuator to the target position. The driver determines the first step drive current of the operating actuator based on the second maximum drive current range of the reference actuator, the second step drive current of the reference actuator, and the first maximum drive current range of the operating actuator. The first step drive current of the actuator corresponds to a value obtained by multiplying the second step drive current by the ratio of the first maximum drive current range to the second maximum drive current range.

9. The system for driving an actuator according to claim 8, wherein, The driver includes: A digital-to-analog converter configured to convert the control signal input from the controller into an analog voltage and output the converted analog voltage; A current sensing unit configured to sense the current of the operating actuator and generate a first sensing signal; A gain adjustment unit is configured to calculate a gain based on a first maximum drive current range of the operating actuator and a second maximum drive current range of a reference actuator, and to convert the first sensing signal into a second sensing signal based on the gain. An error amplifier configured to amplify the error between the second sensing signal output from the gain adjustment unit and the analog control signal output from the digital-to-analog converter; and An actuator drive circuit is configured to generate a drive current for the operating actuator based on a signal output from the error amplifier and to output the generated drive current to the operating actuator.

10. The system for driving an actuator according to claim 9, wherein, The gain adjustment unit calculates the ratio of the second maximum drive current range to the first maximum drive current range as the gain.

11. The system for driving an actuator according to claim 9, wherein, The digital-to-analog converter outputs the analog voltage while simultaneously adding a step current to the analog voltage. The actuator drive circuit outputs the drive current while increasing the drive current with the first step drive current. and The first step drive current of the actuator drive circuit is different from the step current of the digital-to-analog converter.

12. The system for driving an actuator according to claim 11, wherein, The first step drive current of the actuator drive circuit corresponds to the ratio of the step current of the digital-to-analog converter to the gain.

13. The system for driving an actuator according to claim 9, wherein, The error amplifier calculates the ratio of the second sensing signal to the analog control signal as the error ratio, and multiplies the analog voltage by the reciprocal of the error ratio.

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