A transportable data storage transfer device

Abstract

The utility model discloses a movable data storage transfer device belongs to data storage technical field, solved in the application process of movable data storage transfer device, because the USB interface module of mobile hard disk is frequently plugged in and leads to the soldering point drop, interface virtual connection or electrostatic breakdown, and thus make the hard disk light but the problem of unable identification. Including mobile hard disk body, be provided with the light emitting diode on the shell of mobile hard disk body, mobile hard disk body includes USB interface module, and the USB interface module and light emitting diode between electric connection has USB interface physical fault detection circuit, and USB interface physical fault detection circuit real -time monitoring USB interface D module's impedance change and electrostatic impact to identify soldering point drop, virtual connection or breakdown failure and drive LED light alarm. In the utility model, through real -time monitoring USB interface D+ signal line's impedance change and electrostatic impact, identify soldering point drop, virtual connection or breakdown failure, and drive LED light alarm.

Description

Technical Field

[0001] This utility model relates to the field of data storage technology, and in particular to a portable data storage and transfer device. Background Technology

[0002] Portable data storage and transfer devices are essentially portable hard drives, a type of portable data storage device that uses hard disk drives or flash memory chips as storage media, along with a casing and interfaces. Common interfaces include USB and Type-C, supporting plug-and-play functionality. They offer large capacities, ranging from tens of GB to several TB, and boast fast transfer speeds. They can be used to back up documents, videos, photos, and other data, facilitating file transfer between computers, televisions, and other devices. Due to their small size and portability, they are widely applicable to personal and office scenarios, meeting the needs for large-capacity data storage and flexible transfer, making them a commonly used tool for data management.

[0003] In the application of portable data storage and transfer devices, frequent plugging and unplugging of the USB interface module of the portable hard drive can cause solder joints to fall off, the interface to become loose, or electrostatic discharge to occur, which can cause the hard drive light to illuminate but not be recognized.

[0004] Therefore, a portable data storage and transfer device is proposed to solve or alleviate the above problems. Utility Model Content

[0005] The purpose of this invention is to address the shortcomings of existing technologies by proposing a portable data storage and transfer device.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A portable data storage and transfer device includes a portable hard drive body. A light-emitting diode (LED) is disposed on the casing of the portable hard drive body. The portable hard drive body includes a USB interface module. A USB interface physical fault detection circuit is electrically connected between the USB interface module and the LED. The USB interface physical fault detection circuit monitors the impedance change and electrostatic discharge of the USB interface module in real time to identify solder joint detachment, loose connection or breakdown faults and drive the LED light alarm.

[0008] Preferably, the USB interface physical fault detection circuit includes an electrostatic discharge (ESD) detection module, an impedance detection module, a reference voltage module, a fault determination module, and an indication output module.

[0009] The signal output terminal of the USB interface module is connected to the input terminal of the impedance detection module and the input terminal of the electrostatic discharge (ESD) detection module. The output terminal of the impedance detection module is connected to the signal input terminal of the fault decision module. The output terminal of the ESD detection module is connected to the signal input terminal of the fault decision module. The reference voltage output terminal of the reference voltage module is connected to the input terminal of the fault decision module. The logic output terminal of the fault decision module is connected to the drive signal input terminal of the indicator output module. The output terminal of the indicator output module is electrically connected to the light-emitting diode (LED).

[0010] Preferably, the impedance detection module includes a first current-limiting resistor, a first filter capacitor, a first pull-up resistor, and a first operational amplifier in an LM358 dual operational amplifier. The first end of the first current-limiting resistor is connected to the signal terminal of the USB interface module, the second end of the first current-limiting resistor is connected to the non-inverting input terminal of the first operational amplifier in the LM358 dual operational amplifier, the first end of the first filter capacitor is connected to the non-inverting input terminal of the first operational amplifier in the LM358 dual operational amplifier, the second end of the first filter capacitor is grounded, the first end of the first pull-up resistor is energized, the second end of the first pull-up resistor is connected to the non-inverting input terminal of the first operational amplifier in the LM358 dual operational amplifier, and the output terminal of the first operational amplifier in the LM358 dual operational amplifier serves as the output terminal of the impedance detection module.

[0011] Preferably, the electrostatic discharge (ESD) detection module includes a 1N4148 high-speed diode, a first discharge resistor, a first energy storage capacitor, a first feedback resistor, and a second operational amplifier in an LM358 dual operational amplifier. The anode of the 1N4148 high-speed diode is connected to the signal terminal of the USB interface module, and the cathode of the 1N4148 high-speed diode is connected to the non-inverting input terminal of the second operational amplifier in the LM358 dual operational amplifier. The first terminal of the first discharge resistor is connected to the non-inverting input terminal of the second operational amplifier in the LM358 dual operational amplifier, and the second terminal of the first discharge resistor is grounded. The first terminal of the first energy storage capacitor is connected to the non-inverting input terminal of the second operational amplifier in the LM358 dual operational amplifier, and the second terminal of the first energy storage capacitor is grounded. The first terminal of the first feedback resistor is connected to the output terminal of the second operational amplifier in the LM358 dual operational amplifier, and the second terminal of the first feedback resistor is connected to the non-inverting input terminal of the second operational amplifier in the LM358 dual operational amplifier. The output terminal of the second operational amplifier in the LM358 dual operational amplifier serves as the output terminal of the ESD detection module.

[0012] Preferably, the reference voltage module includes a TL431 reference source, a first voltage divider resistor, a second voltage divider resistor, and a third voltage divider resistor. The cathode of the TL431 reference source is connected to the ground, the anode of the TL431 reference source is grounded through the first voltage divider resistor, the first end of the second voltage divider resistor is connected to the reference end of the TL431 reference source, the second end of the second voltage divider resistor outputs a first reference voltage, the first end of the third voltage divider resistor is connected to the reference end of the TL431 reference source, and the second end of the third voltage divider resistor outputs a second reference voltage.

[0013] Preferably, the fault determination module includes an LM393 dual voltage comparator and a CD4071 OR gate chip. The inverting input of the first comparator in the LM393 dual voltage comparator is connected to the output of the impedance detection module. The non-inverting input of the first comparator in the LM393 dual voltage comparator is connected to the first reference voltage of the reference voltage module. The non-inverting input of the second comparator in the LM393 dual voltage comparator is connected to the output of the impedance detection module. The inverting input of the second comparator in the LM393 dual voltage comparator is connected to the second reference voltage of the reference voltage module. The first input of the first OR gate in the CD4071 OR gate chip is connected to the LM393 dual voltage comparator. The output of the first comparator in the voltage comparator is connected to the output of the second comparator in the LM393 dual voltage comparator. The input of the second OR gate in the CD4071 OR gate is connected to the output of the electrostatic discharge (ESD) detection module. The first input of the third OR gate in the CD4071 OR gate is connected to the output of the first OR gate in the CD4071 OR gate. The second input of the third OR gate in the CD4071 OR gate is connected to the output of the second OR gate in the CD4071 OR gate. The output of the third OR gate in the CD4071 OR gate serves as the output of the fault decision module.

[0014] Preferably, the indicator output module includes a first base resistor, an NPN transistor, and a second current-limiting resistor. The first end of the first base resistor is connected to the output terminal of the fault judgment module, the second end of the first base resistor is connected to the base of the NPN transistor, the emitter of the NPN transistor is grounded, the collector of the NPN transistor is connected to the cathode of the light-emitting diode, the first end of the second current-limiting resistor is energized, and the second end of the second current-limiting resistor is connected to the anode of the light-emitting diode.

[0015] Preferably, the USB interface module includes a USB Type-A interface.

[0016] This utility model has the following beneficial effects:

[0017] This invention identifies faults such as solder joint detachment, loose connection, or breakdown by real-time monitoring of the impedance change and electrostatic discharge of the USB interface D+ signal line, and drives LED lights to sound an alarm. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the structure of this utility model;

[0020] Figure 2 This is a structural block diagram of the USB interface physical fault detection circuit in this utility model.

[0021] 1. Portable hard drive body; 2. Light-emitting diode; 3. USB interface module; 4. Electrostatic discharge detection module; 5. Impedance detection module; 6. Reference voltage module; 7. Fault judgment module; 8. Indicator output module. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0023] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0024] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0025] In the description of this utility model, it should be understood that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the utility model product is in use, or the orientation or positional relationship commonly understood by those skilled in the art. They are only used to facilitate the description of this utility model and to simplify the description, and are not intended to indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0026] Furthermore, the terms "first," "second," and "third" are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0027] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0028] A portable data storage and transfer device, such as Figure 1 As shown, the device includes a portable hard drive body 1, with a light-emitting diode 2 mounted on the casing of the portable hard drive body 1. The portable hard drive body 1 includes a USB interface module 3USB, and a USB interface physical fault detection circuit is electrically connected between the USB interface module 3USB and the light-emitting diode 2. The USB interface physical fault detection circuit monitors the impedance changes and electrostatic discharge of the USB interface module in real time to identify solder joint detachment, loose connection or breakdown faults and drive the LED light alarm. The USB interface module 3USB includes a USB interface Type-A.

[0029] like Figure 2As shown, the USB interface physical fault detection circuit includes an electrostatic discharge (ESD) detection module 4, an impedance detection module 5, a reference voltage module 6, a fault decision module 7, and an indicator output module 8. The signal output terminal of the USB interface module 3 is connected to the input terminal of the impedance detection module 5 and the input terminal of the ESD detection module 4. The output terminal of the impedance detection module 5 is connected to the signal input terminal of the fault decision module 7. The output terminal of the ESD detection module 4 is connected to the signal input terminal of the fault decision module 7. The reference voltage output terminal of the reference voltage module 6 is connected to the input terminal of the fault decision module 7. The logic output terminal of the fault decision module 7 is connected to the drive signal input terminal of the indicator output module 8. The output terminal of the indicator output module 8 is electrically connected to the light-emitting diode 2.

[0030] The impedance detection module 5 includes a first current-limiting resistor, a first filter capacitor, a first pull-up resistor, and a first operational amplifier in the LM358 dual operational amplifier. The first end of the first current-limiting resistor is connected to the signal terminal of the USB interface module 3, and the second end of the first current-limiting resistor is connected to the non-inverting input terminal of the first operational amplifier in the LM358 dual operational amplifier. The first end of the first filter capacitor is connected to the non-inverting input terminal of the first operational amplifier in the LM358 dual operational amplifier, and the second end of the first filter capacitor is grounded. The first end of the first pull-up resistor is energized, and the second end of the first pull-up resistor is connected to the non-inverting input terminal of the first operational amplifier in the LM358 dual operational amplifier. The output terminal of the first operational amplifier in the LM358 dual operational amplifier serves as the output terminal of the impedance detection module 5.

[0031] The electrostatic discharge (ESD) detection module 4 includes a 1N4148 high-speed diode, a first discharge resistor, a first energy storage capacitor, a first feedback resistor, and a second operational amplifier in an LM358 dual operational amplifier. The anode of the 1N4148 high-speed diode is connected to the signal terminal of the USB interface module 3 (USB), and the cathode of the 1N4148 high-speed diode is connected to the non-inverting input terminal of the second operational amplifier in the LM358 dual operational amplifier. The first end of the first discharge resistor is connected to the non-inverting input terminal of the second operational amplifier in the LM358 dual operational amplifier, and the second end of the first discharge resistor is grounded. The first end of the first energy storage capacitor is connected to the non-inverting input terminal of the second operational amplifier in the LM358 dual operational amplifier, and the second end of the first energy storage capacitor is grounded. The first end of the first feedback resistor is connected to the output terminal of the second operational amplifier in the LM358 dual operational amplifier, and the second end of the first feedback resistor is connected to the non-inverting input terminal of the second operational amplifier in the LM358 dual operational amplifier. The output terminal of the second operational amplifier in the LM358 dual operational amplifier serves as the output terminal of the ESD detection module 4.

[0032] The reference voltage module 6 includes a TL431 reference source, a first voltage divider resistor, a second voltage divider resistor, and a third voltage divider resistor. The cathode of the TL431 reference source is connected to the ground, and the anode of the TL431 reference source is grounded through the first voltage divider resistor. The first end of the second voltage divider resistor is connected to the reference end of the TL431 reference source, and the second end of the second voltage divider resistor outputs the first reference voltage. The first end of the third voltage divider resistor is connected to the reference end of the TL431 reference source, and the second end of the third voltage divider resistor outputs the second reference voltage.

[0033] Fault determination module 7 includes an LM393 dual voltage comparator and a CD4071 OR gate chip. The inverting input of the first comparator in the LM393 dual voltage comparator is connected to the output of the impedance detection module 5. The non-inverting input of the first comparator in the LM393 dual voltage comparator is connected to the first reference voltage of the reference voltage module 6. The non-inverting input of the second comparator in the LM393 dual voltage comparator is connected to the output of the impedance detection module 5. The inverting input of the second comparator in the LM393 dual voltage comparator is connected to the second reference voltage of the reference voltage module 6. The first input of the first OR gate in the CD4071 OR gate chip is connected to the LM393 dual voltage comparator. The output of the first comparator in the voltage comparator is connected to the output of the second comparator in the LM393 dual voltage comparator. The input of the second OR gate in the CD4071 OR gate is connected to the output of the electrostatic discharge detection module 4. The first input of the third OR gate in the CD4071 OR gate is connected to the output of the first OR gate in the CD4071 OR gate. The second input of the third OR gate in the CD4071 OR gate is connected to the output of the second OR gate in the CD4071 OR gate. The output of the third OR gate in the CD4071 OR gate serves as the output of the fault judgment module 7.

[0034] The indicator output module 8 includes a first base resistor, an NPN transistor, and a second current-limiting resistor. The first end of the first base resistor is connected to the output terminal of the fault judgment module 7, the second end of the first base resistor is connected to the base of the NPN transistor, the emitter of the NPN transistor is grounded, the collector of the NPN transistor is connected to the cathode of the light-emitting diode 2, the first end of the second current-limiting resistor is energized, and the second end of the second current-limiting resistor is connected to the anode of the light-emitting diode 2.

[0035] When the data storage and transfer device, which is actually a portable hard drive, is connected to the USB interface, the D+ signal terminal of the USB interface module 3 transmits the high-frequency signal required for data communication in real time. This signal is first diverted to the impedance detection module 5 and the electrostatic discharge detection module 4 for parallel processing.

[0036] In impedance detection module 5, the D+ signal is input to the non-inverting input of the first operational amplifier in the LM358 dual operational amplifier through the first current limiting resistor. At the same time, the first filter capacitor filters out high-frequency noise, and the first pull-up resistor stabilizes the detection point voltage within the standard operating range.

[0037] When a solder joint falls off or an interface becomes loose, the abnormal change in the impedance of the D+ line causes the voltage at the non-inverting input of the first operational amplifier in the LM358 dual operational amplifier to deviate from the threshold. If the circuit is open, the voltage will rise and exceed the threshold. If the connection is loose, the voltage will fluctuate violently within the range.

[0038] Meanwhile, the electrostatic discharge (ESD) detection module 4 captures transient pulses on the D+ line through the 1N4148 high-speed diode. When ESD generates a voltage exceeding the peak voltage, the cathode potential of the 1N4148 high-speed diode is raised and quickly charged through the first energy storage capacitor, triggering a voltage change at the non-inverting input of the second operational amplifier in the LM358 dual operational amplifier, and its output then generates a fault pulse.

[0039] After the two detection signals are input to the fault judgment module 7, the threshold judgment is performed by the LM393 dual voltage comparator. The first comparator in the LM393 dual voltage comparator compares the output voltage of the first operational amplifier in the LM358 dual operational amplifier with the 1.5V reference generated by the reference voltage module 6. If it is lower than this value, it is judged as a short circuit fault.

[0040] In the LM393 dual voltage comparator, the second comparator compares the same signal with a 2.5V reference; if the value is higher than this, it is considered an open circuit.

[0041] The output signal of the LM393 dual voltage comparator and the electrostatic pulse signal of the second operational amplifier in the LM358 dual operational amplifier are input together into the CD4071 OR gate chip for logic fusion.

[0042] The first OR gate in the CD4071 OR chip receives the comparison result between the output of the first comparator and the output of the second comparator in the LM393 dual voltage comparator. The second OR gate in the CD4071 OR chip receives the pulse signal from the output of the electrostatic discharge detection module 4. Finally, the third OR gate in the CD4071 OR chip performs an OR operation on the previous stage signal. When any fault condition is met, the third OR gate in the CD4071 OR chip outputs a high level.

[0043] The high-level drive indicator module 8 turns on the NPN transistor, which illuminates the LED 2 connected in series with the second current-limiting resistor. This provides a constant-on alarm for open circuit / short circuit / electrostatic breakdown. However, in case of a loose connection fault, the voltage fluctuation causes the comparator output to oscillate, resulting in the LED 2 flashing at a frequency of 1-5Hz.

[0044] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A portable data storage and transfer device, characterized in that, The device includes a portable hard drive body (1), on which a light-emitting diode (2) is provided. The portable hard drive body (1) includes a USB interface module (3). A USB interface physical fault detection circuit is electrically connected between the USB interface module (3) and the light-emitting diode (2). The USB interface physical fault detection circuit monitors the impedance change and electrostatic shock of the USB interface module in real time to identify solder joint detachment, loose connection or breakdown faults and drive the LED light alarm.

2. The portable data storage and transfer device according to claim 1, characterized in that, The USB interface physical fault detection circuit includes an electrostatic discharge (ESD) detection module (4), an impedance detection module (5), a reference voltage module (6), a fault decision module (7), and an indication output module (8). The signal output terminal of the USB interface module (3) is connected to the input terminal of the impedance detection module (5) and the input terminal of the electrostatic shock detection module (4). The output terminal of the impedance detection module (5) is connected to the signal input terminal of the fault decision module (7). The output terminal of the electrostatic shock detection module (4) is connected to the signal input terminal of the fault decision module (7). The reference voltage output terminal of the reference voltage module (6) is connected to the input terminal of the fault decision module (7). The logic output terminal of the fault decision module (7) is connected to the drive signal input terminal of the indicator output module (8). The output terminal of the indicator output module (8) is electrically connected to the light-emitting diode (2).

3. The portable data storage and transfer device according to claim 2, characterized in that, The impedance detection module (5) includes a first current-limiting resistor, a first filter capacitor, a first pull-up resistor, and a first operational amplifier in the LM358 dual operational amplifier. The first end of the first current-limiting resistor is connected to the signal terminal of the USB interface module (3), the second end of the first current-limiting resistor is connected to the non-inverting input terminal of the first operational amplifier in the LM358 dual operational amplifier, the first end of the first filter capacitor is connected to the non-inverting input terminal of the first operational amplifier in the LM358 dual operational amplifier, the second end of the first filter capacitor is grounded, the first end of the first pull-up resistor is energized, and the second end of the first pull-up resistor is connected to the non-inverting input terminal of the first operational amplifier in the LM358 dual operational amplifier. The output terminal of the first operational amplifier in the LM358 dual operational amplifier serves as the output terminal of the impedance detection module (5).

4. A portable data storage and transfer device according to claim 2, characterized in that, The electrostatic discharge (ESD) detection module (4) includes a 1N4148 high-speed diode, a first discharge resistor, a first energy storage capacitor, a first feedback resistor, and a second operational amplifier in an LM358 dual operational amplifier. The anode of the 1N4148 high-speed diode is connected to the signal terminal of the USB interface module (3), and the cathode of the 1N4148 high-speed diode is connected to the non-inverting input terminal of the second operational amplifier in the LM358 dual operational amplifier. The first end of the first discharge resistor is connected to the non-inverting input terminal of the second operational amplifier in the LM358 dual operational amplifier, and the second end of the first discharge resistor is grounded. The first end of the first energy storage capacitor is connected to the non-inverting input terminal of the second operational amplifier in the LM358 dual operational amplifier, and the second end of the first energy storage capacitor is grounded. The first end of the first feedback resistor is connected to the output terminal of the second operational amplifier in the LM358 dual operational amplifier, and the second end of the first feedback resistor is connected to the non-inverting input terminal of the second operational amplifier in the LM358 dual operational amplifier. The output terminal of the second operational amplifier in the LM358 dual operational amplifier serves as the output terminal of the ESD detection module (4).

5. A portable data storage and transfer device according to claim 2, characterized in that, The reference voltage module (6) includes a TL431 reference source, a first voltage divider resistor, a second voltage divider resistor, and a third voltage divider resistor. The cathode of the TL431 reference source is connected to the ground, the anode of the TL431 reference source is grounded through the first voltage divider resistor, the first end of the second voltage divider resistor is connected to the reference end of the TL431 reference source, the second end of the second voltage divider resistor outputs a first reference voltage, the first end of the third voltage divider resistor is connected to the reference end of the TL431 reference source, and the second end of the third voltage divider resistor outputs a second reference voltage.

6. A portable data storage and transfer device according to claim 2, characterized in that, The fault determination module (7) includes an LM393 dual voltage comparator and a CD4071 OR gate chip. The inverting input of the first comparator in the LM393 dual voltage comparator is connected to the output of the impedance detection module (5). The non-inverting input of the first comparator in the LM393 dual voltage comparator is connected to the first reference voltage of the reference voltage module (6). The non-inverting input of the second comparator in the LM393 dual voltage comparator is connected to the output of the impedance detection module (5). The inverting input of the second comparator in the LM393 dual voltage comparator is connected to the second reference voltage of the reference voltage module (6). The first input of the first OR gate in the CD4071 OR gate chip is connected to the LM393 dual voltage comparator. The output of the first comparator in the 93 dual voltage comparator is connected to the output of the second comparator in the LM393 dual voltage comparator. The input of the second OR gate in the CD4071 OR gate chip is connected to the output of the electrostatic discharge detection module (4). The first input of the third OR gate in the CD4071 OR gate chip is connected to the output of the first OR gate in the CD4071 OR gate chip. The second input of the third OR gate in the CD4071 OR gate chip is connected to the output of the second OR gate in the CD4071 OR gate chip. The output of the third OR gate in the CD4071 OR gate chip serves as the output of the fault judgment module (7).

7. A portable data storage and transfer device according to claim 2, characterized in that, The indicator output module (8) includes a first base resistor, an NPN transistor, and a second current-limiting resistor. The first end of the first base resistor is connected to the output terminal of the fault judgment module (7), the second end of the first base resistor is connected to the base of the NPN transistor, the emitter of the NPN transistor is grounded, the collector of the NPN transistor is connected to the cathode of the light-emitting diode (2), the first end of the second current-limiting resistor is energized, and the second end of the second current-limiting resistor is connected to the anode of the light-emitting diode (2).

8. A portable data storage and transfer device according to claim 2, characterized in that, The USB interface module (3) includes a USB interface Type-A.

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