Product detection device and detection method

Abstract

The invention provides a product detection device and method. The device comprises a PWM signal generation circuit, a signal amplification circuit, a comparison circuit and an indication circuit. Wherein the PWM signal generation circuit is used for generating an initial PWM signal and transmitting the initial PWM signal to the signal amplification circuit; the signal amplification circuit is used for amplifying the initial PWM signal, acquiring an amplified signal and transmitting the amplified signal to a to-be-detected product; the comparison circuit is used for comparing an output signal which is output by the signal line end of the product to be detected and corresponds to the amplification signal with a preset reference voltage, and outputting a comparison result to the indication circuit; and the indicating circuit is used for displaying the comparison result. According to the invention, bad detection can be carried out on a product of a transmission line with a blocking function.

Description

Technical Field

[0001] The present invention relates to the technical field of product detection, and more specifically, to a product detection device and a detection method thereof. Background Art

[0002] With the development of consumer electronic products and the continuous improvement of technology, users have higher and higher performance requirements for such products. In order to ensure that the products can enter the market with qualification, relevant functional tests are usually carried out on them before they are assembled or shipped.

[0003] Most existing electronic products have high-speed signal communication capabilities. When testing the circuits of such products, many high-speed signal transmission lines have DC blocking capacitors, making it impossible to use a conventional multimeter or a DC power supply method to directly measure the open and short circuits of the entire line. Using a segmented measurement method not only results in excessively long test times, but also causes irreparable damage to the product due to the high error rate of segmented measurement. Summary of the Invention

[0004] In view of the above problems, an object of the present invention is to provide a product detection device and detection method, which can detect products with transmission lines having a DC isolation function and improve detection efficiency.

[0005] The product detection device provided by the present invention includes a PWM signal generating circuit, a signal amplifying circuit, a comparison circuit and an indication circuit; wherein the PWM signal generating circuit is used to generate an initial PWM signal and transmit it to the signal amplifying circuit; the signal amplifying circuit is used to amplify the initial PWM signal, obtain the amplified signal and transmit it to the product to be detected; the comparison circuit is used to compare the output signal corresponding to the amplified signal outputted from the signal line end of the product to be detected with a preset reference voltage, and output the comparison result to the indication circuit; the indication circuit is used to display the comparison result.

[0006] In addition, an optional technical solution is to provide a DC blocking capacitor in the circuit of the product to be tested; the amplified signal is a bidirectional signal with a set frequency, and the amplified signal is used to be transmitted through the DC blocking capacitor.

[0007] In addition, an optional technical solution is to provide a reverse diode connected to the ground terminal of the wire in the circuit of the product to be detected, and transmit the amplified signal to the circuit of the product to be detected through the ground terminal of the wire of the product to be detected.

[0008] In addition, an optional technical solution is that the signal amplification circuit includes an operational amplifier.

[0009] In addition, an optional technical solution is that the reference voltage includes a short-circuit reference voltage and an open-circuit reference voltage; the short-circuit reference voltage is a negative voltage, and the open-circuit reference voltage is a positive voltage.

[0010] In addition, an optional technical solution is that when the voltage of the output signal is lower than the short-circuit reference voltage, it indicates that the circuit of the product to be tested is short-circuited to the ground; when the voltage of the output signal is greater than the short-circuit reference voltage and lower than the open-circuit reference voltage, it indicates that the circuit of the product to be tested is open.

[0011] In addition, an optional technical solution is that the indicating circuit includes a driving circuit and an LED module connected to the driving circuit; wherein the driving circuit is used to control the corresponding color light in the LED module to light up according to the comparison result.

[0012] In addition, an optional technical solution is that when the circuit of the product to be detected is short-circuited to the ground, the comparison circuit outputs a low level to the enable end of the drive circuit; when the circuit of the product to be detected is open, the comparison circuit outputs a high level to the enable end of the drive circuit.

[0013] On the other hand, the present invention also provides a product detection method, which uses the above-mentioned product detection device to detect the product to be detected, and the method includes: controlling the PWM signal generating circuit to generate an initial PWM signal; amplifying the initial PWM signal to obtain a corresponding amplified signal; obtaining an output signal output by the product to be detected that corresponds to the amplified signal; comparing the output signal with a preset reference voltage, determining the detection result and displaying the detection result.

[0014] In addition, an optional technical solution is that the test results of the product to be tested include good products and defective products; wherein the defective types of the defective products include open circuit defects and short circuit defects.

[0015] By using the above-mentioned product detection device and detection method, a PWM signal with a fixed frequency and level is provided, and then the corresponding signal data is output from the signal line end of the product after amplification and driving. Since a PWM signal is used, the signal end with a DC blocking capacitor can also be detected, thereby realizing the automatic detection of the circuit with DC blocking function, avoiding the problem of damage easily caused by manual segmented detection, and greatly improving the test efficiency.

[0016] In order to achieve the above and related purposes, one or more aspects of the present invention include the features that will be described in detail later. The following description and the accompanying drawings describe some exemplary aspects of the present invention in detail. However, these aspects indicate only some of the various ways in which the principles of the present invention can be used. In addition, the present invention is intended to include all of these aspects and their equivalents. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] By referring to the following description in conjunction with the accompanying drawings, and with a more complete understanding of the present invention, other objects and results of the present invention will become more clear and easy to understand. In the accompanying drawings:

[0018] Figure 1 is a schematic diagram of a product detection device according to an embodiment of the present invention;

[0019] Figure 2 Flowchart of a product detection method according to an embodiment of the present invention.

[0020] The same reference numerals throughout the drawings indicate similar or corresponding features or functions. DETAILED DESCRIPTION

[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0022] In the following description, for illustrative purposes, numerous specific details are set forth to provide a comprehensive understanding of one or more embodiments. However, it will be apparent that the embodiments may be practiced without these specific details. In other instances, well-known structures and devices are shown in block diagram form to facilitate description of one or more embodiments.

[0023] In the description of the present invention, it should be understood that the orientations or positional relationships indicated by the following terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the content or structure of the present invention.

[0024] To address the existing problem of transmission lines with DC blocking capacitors, it is not possible to use a conventional multimeter or a DC power supply method to directly measure the open and short circuits of the entire line. Instead, a segmented measurement method is used. This method not only results in excessively long test times, but also causes irreparable damage to the product due to the high error rate of segmented measurement. The present invention provides a product detection device and detection method, which uses an amplified PWM signal to input into the circuit of the product to be detected, and then outputs corresponding signal data from the signal line end of the product after driving. The device is suitable for automated product detection with DC blocking capacitor circuits, avoids the damage problem caused by segmented detection, and improves test efficiency.

[0025] To describe the product detection device and detection method of the present invention in detail, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0026] Figure 1 The schematic principle of the product detection device according to the embodiment of the present invention is shown.

[0027] like Figure 1 As shown, the product detection device of the embodiment of the present invention mainly includes: a PWM signal generating circuit, a signal amplifying circuit, a comparison circuit and an indication circuit; wherein the PWM signal generating circuit is used to generate an initial PWM signal and transmit it to the signal amplifying circuit for amplification processing to improve the driving ability and voltage of the PWM signal; the signal amplifying circuit is used to amplify the initial PWM signal and output a PWM_SOURCE signal, that is, the amplified signal and transmit it to the product to be detected; the comparison circuit is used to compare the output signal corresponding to the amplified signal output from the signal line end of the product to be detected with a preset reference voltage, and output the comparison result to the indication circuit; the indication circuit is used to display the comparison result, so that the detection personnel can obtain the detection result in time.

[0028] Specifically, a DC blocking capacitor can be provided in the circuit of the product to be tested, and the amplified signal is a bidirectional signal with a set frequency. The amplified signal can be transmitted through the DC blocking capacitor, thereby realizing direct detection of such circuits; of course, for products whose circuits do not have a DC blocking function, the product detection device of the embodiment of the present invention can also be used for detection.

[0029] In a specific embodiment of the present invention, a reverse diode connected to the ground terminal of the wire is provided in the circuit of the product to be detected, and the amplified signal is transmitted to the circuit of the product to be detected through the ground terminal of the wire of the product to be detected, that is, the reverse diode between the signal line and the ground wire is utilized, so that the detection signal is provided through the ground terminal of the wire or the ground wire end of the product, and a PWM signal with a constant frequency can be received at the signal end of the product for comparison and judgment.

[0030] In which, the signal amplification circuit may include an operational amplifier or an amplification circuit with equivalent functions, and the reference voltage preset in the comparison circuit may include a short-circuit reference voltage (REF_short) and an open-circuit reference voltage (REF_open), wherein the short-circuit reference voltage is set to a negative voltage and the open-circuit reference voltage is a positive voltage. During the comparison process, when the voltage of the output signal is lower than the short-circuit reference voltage, it indicates that the circuit of the product to be tested is short-circuited to the ground; when the voltage of the output signal is greater than the short-circuit reference voltage and lower than the open-circuit reference voltage, it indicates that the circuit of the product to be tested is open. Both situations indicate that the product is unqualified.

[0031] In another embodiment of the present invention, an indicator circuit includes a driver circuit and an LED module connected to the driver circuit; the driver circuit is configured to control the corresponding color of the LED module to illuminate based on the comparison result. When the circuit of the product to be inspected is short-circuited to ground, the comparison circuit outputs a low level to the enable terminal of the driver circuit, which controls the corresponding LED to illuminate via the enable terminal; when the circuit of the product to be inspected is open, the comparison circuit outputs a high level to the enable terminal of the driver circuit, which controls the corresponding LED to illuminate via the enable terminal.

[0032] As an example, when the product to be tested is a qualified product, after comparison by the comparison circuit, it does not meet the conditions for outputting a low level or a high level. At this time, the LED module can maintain the initial state, that is, no LED light is on; and when the product to be tested is unqualified, it will be further judged as a short circuit or an open circuit. At this time, the corresponding LED light display can be controlled according to the level output by the comparison circuit. For example, if the product has a short circuit, the red light will be on, and if the product has an open circuit, the yellow light will be on, etc.

[0033] Corresponding to the above-mentioned product detection device, the present invention also provides a product detection method, which uses the above-mentioned product detection device to detect the product to be detected.

[0034] Specifically, Figure 2 The figure shows a schematic flow of a product detection method according to an embodiment of the present invention.

[0035] like Figure 2 As shown, the product detection method of the embodiment of the present invention mainly includes the following steps:

[0036] S100: Control the PWM signal generating circuit to generate an initial PWM signal;

[0037] S200: Amplify the initial PWM signal to obtain a corresponding amplified signal;

[0038] S300: Acquire an output signal corresponding to the amplified signal output by the product to be detected;

[0039] S400: Compare the output signal with a preset reference voltage, determine a detection result, and display the detection result.

[0040] Among them, the test results of the products to be tested include good products and defective products; among them, the defective types of defective products further include open circuit defects and short circuit defects. These three situations can be displayed to the test personnel through the indicator circuit.

[0041] Specifically, the detection method of the present invention first generates a bidirectional PWM signal through a PWM signal generating circuit. After the PWM signal is processed by an operational amplifier, its driving capability is improved to form a positive and negative voltage level that causes the reverse diode of the signal line to conduct without damaging it, thereby providing a PWM-source signal with strong driving capability and meeting voltage level requirements for subsequent testing.

[0042] In addition, since the product to be tested has a reverse diode connected to the ground inside the chip, the PWM-source signal can be transmitted to the signal line end of the product through the GND line of the product to be tested. The signal output from the signal line end is then input into the comparison circuit. Since the comparison circuit has two voltages, negative REF_short and positive REF_open, as references for short-circuit and open-circuit judgments, respectively, if the voltage is lower than REF_short, it is a short circuit to ground, and the corresponding OUT_L will be output to the LED lamp drive circuit. If it is lower than REF_open, it is an open circuit, and the corresponding OUT_H will be output to the LED drive circuit enable port. Then, the LED module can be observed to see if the light is on to determine whether the product is a good product. If it is a defective product, the color of the lit LED light can be used to determine whether it is a short circuit or an open circuit.

[0043] It should be noted that, for the embodiments of the product detection method, reference may be made to the description in the embodiments of the product detection device, which will not be described in detail here.

[0044] According to the above-mentioned product detection device and detection method, the amplified PWM signal is transmitted to the product, and the reverse diode between the signal line and the ground line is cleverly used to input the PWM signal from the ground line to the product, and the output signal is collected from the signal line end and compared with the reference signal, thereby realizing automatic detection of the line with DC isolation function, avoiding the damage problem caused by manual segmented detection, and greatly improving the testing efficiency and application scope of the product.

[0045] The product inspection device and method according to the present invention are described above by way of example with reference to the accompanying drawings. However, those skilled in the art will appreciate that various modifications may be made to the product inspection device and method described above without departing from the scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A product detection device, characterized in that: It includes a PWM signal generating circuit, a signal amplifying circuit, a comparing circuit and an indicating circuit; wherein, The PWM signal generating circuit is used to generate an initial PWM signal and transmit it to the signal amplifying circuit; The signal amplifying circuit is used to amplify the initial PWM signal, obtain the amplified signal and transmit it to the product to be detected; The comparison circuit is used to compare the output signal corresponding to the amplified signal outputted from the signal line end of the product to be detected with a preset reference voltage, and output the comparison result to the indication circuit; The indicating circuit is used to display the comparison result.

2. The product detection device according to claim 1, characterized in that: A DC blocking capacitor is provided in the circuit of the product to be detected; The amplified signal is a bidirectional signal with a set frequency, and the amplified signal is used for transmission through the DC blocking capacitor.

3. The product detection device according to claim 1, characterized in that: A reverse diode connected to the grounding end of the electric wire is arranged in the circuit of the product to be detected, and the amplified signal is transmitted to the circuit of the product to be detected through the grounding end of the electric wire of the product to be detected.

4. The product detection device according to claim 1, characterized in that: The signal amplifying circuit includes an operational amplifier.

5. The product detection device according to claim 1, characterized in that: The reference voltage includes a short-circuit reference voltage and an open-circuit reference voltage; The short-circuit reference voltage is a negative voltage, and the open-circuit reference voltage is a positive voltage.

6. The product detection device according to claim 5, characterized in that: When the voltage of the output signal is lower than the short-circuit reference voltage, it indicates that the circuit of the product to be detected is short-circuited to the ground; When the voltage of the output signal is greater than the short-circuit reference voltage and lower than the open-circuit reference voltage, it indicates that the circuit of the product to be detected is open.

7. The product detection device according to claim 6, characterized in that: The indicating circuit includes a driving circuit and an LED module connected to the driving circuit; wherein, The driving circuit is used to control the lights of corresponding colors in the LED modules to light up according to the comparison result.

8. The product detection device according to claim 7, characterized in that: When the circuit of the product to be detected is short-circuited to the ground, the comparison circuit outputs a low level to the enable terminal of the drive circuit; When the circuit of the product to be detected is open, the comparison circuit outputs a high level to the enable terminal of the drive circuit.

9. A product detection method, characterized in that: Using the product detection device according to any one of claims 1 to 8 to detect the product to be detected, the method comprises: Controlling the PWM signal generating circuit to generate an initial PWM signal; Amplifying the initial PWM signal to obtain a corresponding amplified signal; Acquire an output signal output by the product to be detected corresponding to the amplified signal; The output signal is compared with a preset reference voltage to determine a detection result and display the detection result.

10. The product detection method according to claim 9, characterized in that: The test results of the product to be tested include good products and defective products; wherein the defective types of the defective products include open circuit defects and short circuit defects.

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