Testing device of camera POC filter circuit

Abstract

The utility model discloses a camera POC filter circuit testing device, the camera POC filter circuit testing device comprises a POC power supply, a plurality of POC filter circuits, a coaxial cable connector and a processor, the POC filter circuits have different signal filtering frequency bands, the POC power supply is connected with the plurality of POC filter circuits, the coaxial cable connector is connected with the coaxial cable connector, and the processor is connected with the coaxial cable connector. The POC filter circuits are connected with the coaxial cable connector, and the coaxial cable connector is further connected with the processor and the camera. According to the utility model, a plurality of POC filter circuits with filtering functions of different signal frequency bands are designed in the testing device for the POC filter circuit of the camera, and the actual effects of POC filtering in the plurality of different POC filter circuits can be tested at the same time by combining with the processor, so that the POC filter circuits with different circuit parameters or different circuit structures can be debugged at the same time; therefore, the POC filter circuit with the best effect can be selected to be applied to the final design of a product, and compared with a test scheme of a domain control board, the test cost is reduced, and the test efficiency is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to camera POC filter circuit test technical field especially relates to a kind of testing device of camera POC filter circuit. BACKGROUND

[0002] Currently, cameras based on GMSL (Gigabit Multimedia Serial Link, a high-speed serial communication protocol) communication have been widely used in vehicles supporting automatic driving functions. Cameras based on GMSL communication complete power supply and data transmission simultaneously through a coaxial cable. Therefore, a POC circuit needs to be designed in the GMSL communication interface. POC (Power Over Coaxia) is a technology for simultaneously transmitting data and power signals based on a coaxial cable. The core of the POC circuit is the design of the POC filter circuit, which affects the working stability and imaging quality of the camera.

[0003] In vehicles supporting automatic driving functions, the camera video signal is usually processed by a domain control unit, so the GMSL communication interface is usually designed on the domain control board. Therefore, the current POC filter circuit debugging is directly performed on the domain control board. The POC filter circuit has been designed in the completed domain control board, and only the basic device parameters can be changed during the debugging stage, making it difficult to adjust the circuit architecture. Therefore, it is not convenient to directly use the domain control board to complete the POC filter circuit debugging, which reduces the debugging efficiency. Moreover, the cost of a set of domain control board is high, increasing the debugging cost of the POC filter circuit. SUMMARY

[0004] In view of the above at least one problem existing in the prior art, the present utility model provides a testing device for a camera POC filter circuit to overcome at least one of the above problems.

[0005] To achieve the above-mentioned purpose, the utility model adopts the following technical scheme:

[0006] According to one aspect of the present utility model, a testing device for a camera POC filter circuit is provided, wherein the testing device for the camera POC filter circuit comprises a POC power supply, multiple POC filter circuits, a coaxial cable connector, and a processor. The POC filter circuits have different signal filtering frequency bands. The POC power supply is connected to the multiple POC filter circuits. The multiple POC filter circuits are connected to the coaxial cable connector. The coaxial cable connector is further connected to the processor and a camera, respectively.

[0007] Optionally, the POC filter circuit includes a filter capacitor, an inductor, and a resistor, wherein the filter capacitor is connected in series with the inductor, and the resistor is connected in parallel with the inductor.

[0008] Optionally, various POC filter circuits may include different numbers of inductors and resistors.

[0009] Optionally, the coaxial cable connector is a multi-channel coaxial cable connector, which is connected to multiple cameras.

[0010] Optionally, the testing device for the camera POC filter circuit includes a deserializer, which is connected to the processor and the coaxial cable connector respectively.

[0011] Optionally, the deserializer is a GMSL deserializer, and the GMSL deserializer is connected to the coaxial cable connector via a GMSL bus.

[0012] Optionally, the GMSL bus includes multiple buses, and various POC filter circuits are connected one-to-one to the multiple GMSL buses.

[0013] Optionally, each of the GMSL buses is also provided with a DC blocking capacitor.

[0014] Optionally, the POC power supply includes multiple POC power supplies, and each of the multiple POC power supplies is connected to a corresponding POC filter circuit.

[0015] Optionally, the POC power supply is provided with an external power supply connection terminal, which is connected to an external adjustable DC power supply.

[0016] In summary, the beneficial effects of this utility model are:

[0017] This invention relates to a testing device for camera POC filter circuits, comprising: a POC power supply, multiple POC filter circuits, a coaxial cable connector, and a processor. The POC filter circuits have different signal filtering frequency bands. The POC power supply is connected to the multiple POC filter circuits, which are connected to the coaxial cable connector. The coaxial cable connector is also connected to the processor and the camera. This invention designs multiple POC filter circuits with different signal frequency band filtering functions within a single camera POC filter circuit testing device. Combined with the processor, it facilitates simultaneous testing of the actual filtering effects of multiple different POC filter circuits. It can simultaneously debug POC filter circuits with different circuit parameters or different circuit architectures. Furthermore, this camera POC filter circuit testing device allows for the selection of the most effective POC filter circuit for application in the final product design. Compared to domain control board testing solutions, this reduces the testing cost of POC filter circuits and improves testing efficiency. Attached Figure Description

[0018] Figure 1 A schematic diagram of the structure of a test device for a camera POC filter circuit according to this utility model is shown;

[0019] Figure 2 A schematic diagram of the structure of one type of POC filter circuit according to this utility model is shown. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this utility model clearer, the embodiments of this utility model will be described in further detail below with reference to the accompanying drawings.

[0021] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0022] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" 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.

[0023] Example 1

[0024] Figure 1 The diagram shows a structural schematic of a test device for a camera POC filter circuit according to the present invention. The test device for the camera POC filter circuit of the present invention includes: a POC power supply, multiple POC filter circuits, a coaxial cable connector, and a processor. The POC filter circuits have different signal filtering frequency bands. The POC power supply is connected to the multiple POC filter circuits. The multiple POC filter circuits are connected to the coaxial cable connector. The coaxial cable connector is also connected to the processor and the camera respectively.

[0025] The testing device for the camera POC filter circuit of this utility model mainly includes a POC power supply, multiple POC filter circuits, a coaxial cable connector, and a processor. The POC power supply, multiple POC filter circuits, and coaxial cable connector are connected in sequence. The other end of the coaxial cable connector is also connected to an external camera. The power signal from the POC power supply powers the camera in sequence through the POC filter circuit and the coaxial cable connector.

[0026] The POC power supply of this utility model can be powered by a DC-DC power supply or an LDO power supply, etc. Of course, those skilled in the art can flexibly choose the specific type of power supply according to actual needs, and no specific limitation is made here.

[0027] To test the filtering effect of POC filter circuits, this invention designs a variety of POC filter circuits with different structures. Each filter circuit can filter power signals in different frequency bands. The specific structural design can be flexibly set according to actual test requirements, and no specific limitation is made here.

[0028] Coaxial cable connectors are channels for transmitting power and video signals. The POC power supply can power the camera through the coaxial cable connector, while the camera can transmit video signals to the processor through the coaxial cable connector.

[0029] The processor of this invention is connected to a coaxial cable connector. A general-purpose processing processor with certain image processing capabilities, such as a CPU, can be selected. It is mainly used to receive and process the video signal transmitted from the camera through the coaxial cable connector, so as to verify the actual effect of different POC filter circuits based on the image quality of the processed image.

[0030] This invention incorporates multiple POC filter circuits with different signal frequency band filtering functions within a camera POC filter circuit testing device. Combined with a processor, it facilitates simultaneous testing of the actual POC filtering effects of various different POC filter circuits. It can simultaneously debug POC filter circuits with different circuit parameters or different circuit architectures, thereby enabling the selection of the best-performing POC filter circuit for application in the final product design. Compared to the domain control board testing scheme, this invention reduces the testing cost of POC filter circuits and improves testing efficiency.

[0031] In some embodiments of this utility model, the POC filter circuit includes a filter capacitor, an inductor, and a resistor, wherein the filter capacitor is connected in series with the inductor, and the resistor is connected in parallel with the inductor.

[0032] The POC (Power-On-Chip) filter circuit is a crucial component of the camera's POC circuitry. It is responsible for filtering the DC power signal to eliminate noise and interference, ensuring the signal's purity and stability. Simultaneously, the POC filter circuit must also ensure that the normal transmission of high-speed serial signals over coaxial cables remains unaffected.

[0033] Specifically, the POC filter circuit of this invention consists of multiple filter capacitors, inductors, and resistors. The filter capacitors and inductors are connected in series, and the resistors and inductors are connected in parallel. These components are then connected to a coaxial cable connector via series or parallel connections. The inductor has low impedance at low frequencies, allowing DC power to pass through smoothly; while at high frequencies, the inductor has high impedance, blocking high-speed serial signals and preventing signal leakage or interference. The capacitor isolates the DC power supply and the high-speed signal path, ensuring that they do not interfere with each other.

[0034] In some embodiments of this utility model, various POC filter circuits are provided with different numbers of inductors and resistors.

[0035] For ease of understanding of this embodiment, as Figure 2 As shown, schematic diagrams of various POC filter circuits of this utility model are further provided.

[0036] Figure 2 The document provides four structural examples of POC filter circuits, combined with... Figure 1 and Figure 2 The POC filter circuit 1 can effectively isolate signals in the 66MHz to 620MHz frequency band: the DC power supply VCC1 is connected to two inductors after passing through three parallel power supply filter capacitors. For example, the three parallel power supply filter capacitors can be C1 = 10uF, C2 = 0.1uF, and C3 = 1nF. A circuit architecture using two inductors in series is used to isolate high-frequency signals. L1 = 22uH, L2 = 560nH, R1 = 5.1KΩ. R1 is connected in parallel with L1 to ensure a characteristic impedance greater than 1KΩ to prevent high-frequency signals from passing through.

[0037] The POC filter circuit 2 can effectively isolate signals in the 21MHz to 300MHz frequency band: the DC power supply VCC2 is connected to three inductors after passing through three parallel power supply filter capacitors. For example, the three parallel power supply filter capacitors can be C4 = 10uF, C5 = 0.1uF, and C6 = 1nF. A circuit architecture using three inductors in series is used to isolate high-frequency signals. L3 = 22uH, L4 = 2.2uH, L5 = 2.2uH, R2 = 1.5KΩ, R3 = 1.5KΩ. R2 and L3 are connected in parallel, and R3 and L4 are connected in parallel to ensure a characteristic impedance greater than 1KΩ to prevent high-frequency signals from passing through.

[0038] The POC filter circuit 3 can effectively isolate signals in the 6.1MHz to 650MHz frequency band: the DC power supply VCC3 is connected to four inductors after passing through three parallel power supply filter capacitors. For example, the three parallel power supply filter capacitors can be C7 = 10uF, C8 = 0.1uF, and C9 = 1nF. A circuit architecture using four inductors in series is used to isolate high-frequency signals. L6 = 22uH, L7 = 6.8uH, L8 = 470nH, L9 = 470nH, R4 = 5.1KΩ, R5 = 5.1KΩ, R6 = 1.5KΩ. The parallel connections of R4 and L6, R5 and L7, and R6 and L8 ensure a characteristic impedance greater than 1KΩ to prevent high-frequency signals from passing through.

[0039] The POC filter circuit 4 can effectively isolate signals in the 20MHz to 2250MHz frequency band: the DC power supply VCC4 is connected to six inductors after passing through three parallel power supply filter capacitors. For example, the three parallel power supply filter capacitors can be C10 = 10uF, C11 = 0.1uF, and C12 = 1nF. The circuit architecture using six inductors in series is used to isolate high-frequency signals. L10 = 15uH, L11 = 6.8uH, L12 = 2.2uH, L13 = 47nH, L14 = 47nH, L15 = 47nH, R7 = 5.1KΩ, R8 = 5.1KΩ, R9 = 1.5KΩ. R10 and R11 are reserved resistors. Connecting R7 in parallel with L10, R8 in parallel with L11, R9 in parallel with L12, R10 in parallel with L13, and R11 in parallel with L14 ensures a characteristic impedance greater than 1KΩ to block high-frequency signals. Optionally, other components with different parameters can be soldered to further select suitable circuit parameters.

[0040] It should be noted that the above-mentioned various POC filter circuit structures are merely examples of this utility model. Those skilled in the art can flexibly adjust the various POC filter circuits according to actual testing needs, and no specific limitations are made here.

[0041] In some embodiments of this utility model, the coaxial cable connector is a multi-channel coaxial cable connector, which is connected to a multi-channel camera.

[0042] The coaxial cable connector of this invention can be a multi-channel coaxial cable connector. The number of channels in the multi-channel coaxial cable connector corresponds to the number of cameras connected. For example, when connecting four GMSL cameras, a four-channel coaxial cable connector can be used. As a specific implementation, the four-channel coaxial cable connector of this invention can be the FAKRA connector 818024869 from Elec-Tech International. Of course, other models can also be selected according to actual needs.

[0043] The coaxial cable connector of this invention is an integrated multi-channel coaxial cable connector, which can simultaneously connect multiple GMSL cameras, reducing the interface size and saving space.

[0044] In some embodiments of this utility model, the testing device for the camera POC filter circuit includes a deserializer, which is connected to the processor and the coaxial cable connector respectively.

[0045] The testing device for the camera POC filter circuit of this utility model includes a deserializer. One end of the deserializer is connected to a coaxial cable connector, and the other end is connected to a processor. It is mainly used to deserialize the serial signal transmitted from the coaxial cable connector and then transmit it to the processor for subsequent processing to meet the signal processing requirements of the processor.

[0046] In some embodiments of this utility model, the deserializer is a GMSL deserializer, and the GMSL deserializer is connected to the coaxial cable connector via a GMSL bus.

[0047] Corresponding to the settings of the GMSL camera, the deserializer of this invention can be a GMSL deserializer. The GMSL deserializer is connected to the coaxial cable connector via a GMSL bus. As a specific implementation, the GMSL deserializer of this invention can use the Maxim Integrated MAX96712 chip. This serial deserializer supports MIPI bus communication and has four GMSL bus communication interfaces, namely PORTA, PORTB, PORTC, and PORTD. Of course, other models of serial deserializers can be selected according to actual needs, and no specific limitation is made here.

[0048] In some embodiments of this utility model, the GMSL bus includes multiple buses, and various POC filter circuits are connected one-to-one to the multiple GMSL buses.

[0049] The multiple filtering circuits to be verified in this invention are independent circuit structures. Therefore, multiple GMSL buses can be set up accordingly, and multiple POC filtering circuits can be connected to multiple GMSL buses one by one, so that each GMSL signal can be transmitted independently on each GMSL bus, and the filtering effect of each POC filtering circuit can be independently verified.

[0050] In some embodiments of this invention, each of the GMSL buses is also provided with a DC blocking capacitor.

[0051] Each GMSL bus communication interface of the GMSL deserializer can be connected in series with a 0.1uF DC blocking capacitor to the GMSL bus. The DC blocking capacitor is mainly used to isolate DC power signals and prevent them from interfering with the transmission of video signals. Of course, those skilled in the art can flexibly choose the appropriate value of the DC blocking capacitor according to actual needs, and no specific limitation is made here.

[0052] In some embodiments of this utility model, the POC power supply includes multiple POC power supplies, and each of the multiple POC power supplies is connected to a corresponding POC filter circuit.

[0053] This invention allows for the provision of multiple POC DC power supplies corresponding to various POC filter circuits, with each power supply connected to a specific POC filter circuit. Using multiple POC DC power supplies enables independent power supply and voltage control for the camera through each POC filter circuit. Alternatively, those skilled in the art can use a single POC DC power supply for unified power supply based on actual needs.

[0054] In some embodiments of this utility model, the POC power supply is provided with an external power supply connection terminal, which is connected to an external adjustable DC power supply.

[0055] The POC power supply of this invention is provided with one or more external power supply connection terminals. An external adjustable DC power supply can supply power to the POC power supply through the external power supply connection terminals. Therefore, the POC power supply voltage in the test device of this invention is adjustable, thereby meeting different debugging requirements.

[0056] In addition, during debugging, the required voltage for different coaxial cable lengths can be determined by adjusting the DC power supply voltage. This is because coaxial cables cause some loss to the camera's power supply voltage, and the longer the coaxial cable, the greater the voltage drop. Therefore, the power supply voltage needs to be increased to avoid undervoltage at the camera end.

[0057] The above description is merely a specific embodiment of this utility model. Under the teachings of this utility model, those skilled in the art can make other improvements or modifications based on the above embodiments. Those skilled in the art should understand that the above specific description is only to better explain the purpose of this utility model, and the scope of protection of this utility model should be determined by the scope of the claims.

Claims

1. A test apparatus for a camera POC filter circuit, wherein, The testing device for the camera POC filter circuit includes: a POC power supply, multiple POC filter circuits, a coaxial cable connector, and a processor. The POC filter circuits have different signal filtering frequency bands. The POC power supply is connected to the multiple POC filter circuits, the multiple POC filter circuits are connected to the coaxial cable connector, and the coaxial cable connector is also connected to the processor and the camera respectively.

2. The test apparatus for the camera POC filter circuit as described in claim 1, wherein, The POC filter circuit includes a filter capacitor, an inductor, and a resistor. The filter capacitor is connected in series with the inductor, and the resistor is connected in parallel with the inductor.

3. The test apparatus for the camera POC filter circuit as described in claim 1, wherein, Various POC filter circuits contain different numbers of inductors and resistors.

4. The test apparatus for the camera POC filter circuit as described in claim 1, wherein, The coaxial cable connector is a multi-channel coaxial cable connector, which is connected to multiple cameras.

5. The test apparatus for the camera POC filter circuit as described in claim 1, wherein, The testing device for the camera POC filter circuit includes a deserializer, which is connected to the processor and the coaxial cable connector respectively.

6. The test apparatus for the camera POC filter circuit as described in claim 5, wherein, The deserializer is a GMSL deserializer, and the GMSL deserializer is connected to the coaxial cable connector via a GMSL bus.

7. The test apparatus for the camera POC filter circuit as described in claim 6, wherein, The GMSL bus includes multiple buses, and various POC filter circuits are connected one-to-one to the multiple GMSL buses.

8. The test apparatus for the camera POC filter circuit as described in claim 7, wherein, Each of the GMSL buses is also equipped with a DC blocking capacitor.

9. The testing apparatus for the camera POC filter circuit as described in claim 1, wherein, The POC power supply includes multiple POC power supplies, and each of the multiple POC power supplies is connected to a corresponding POC filter circuit.

10. The test apparatus for the camera POC filter circuit as described in any one of claims 1 to 9, wherein, The POC power supply is equipped with an external power supply connection terminal, which is connected to an external adjustable DC power supply.

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