CN214473672U - Clamp for verifying influence of capacitance value difference of USB3.0AC coupling capacitor on eye pattern - Google Patents

Abstract

The utility model discloses a verify USB3.0AC coupling capacitance value difference influences anchor clamps of eye pattern, including the PCB board, first TX + input end is connected with first TX + output end through first transmission line on the PCB board, first TX-input end is connected with first TX-output end through the second transmission line, the second TX + input end is connected with second TX + output end through the third transmission line, the second TX-input end is connected with the second TX-output end through the fourth transmission line, the third TX + input end is connected with the third TX + output end through the fifth transmission line, the third TX-input end is connected with the third TX-output end through the sixth transmission line, it has electric capacity C1 to establish ties on the first transmission line, it has electric capacity C2 to establish ties on the second transmission line, it has electric capacity C3 to establish ties on the third transmission line, it has electric capacity C4 to establish ties on the fourth transmission line, it has electric capacity C5 to establish ties on the fifth transmission line, a capacitor C6 is connected in series on the sixth transmission line. The clamp uses few devices, is convenient to manufacture, has the cost of all devices not exceeding 50 yuan, has low cost and has high cost performance.

Description

Clamp for verifying influence of capacitance value difference of USB3.0AC coupling capacitor on eye pattern

Technical Field

The utility model relates to a USB3.0 signal technology field especially relates to a verify that USB3.0AC coupling capacitance holds the anchor clamps that the value difference influences the eye pattern, holds the value through verifying different AC coupling capacitance and carries out the verification of USB3.0 signal, verifies USB 3.0's performance, can reachd the size that USB3.0 signal matches electric capacity in product design phase earlier stage, is applicable to the use of research and development test phase.

Background

In order to ensure that the USB3.0 can normally work, verification under different environments is required, for example, extreme environments such as high temperature and low temperature are required, and the normal verification cannot be performed, so that thinking needs to be changed, a certain mode is used to replace the change of the performance of the USB3.0 under the extreme environment, the verification is performed by changing the capacitance value of the USB3.0AC coupling capacitor, and the condition that the USB3.0 can normally work can be verified through the mode.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to the not enough of above-mentioned prior art, provide an it influences the anchor clamps of eye diagram to verify USB3.0AC coupling electric capacity appearance value difference, through changing the influence of USB3.0AC coupling electric capacity appearance value to observe USB3.0 eye diagram, just can verify out the USB3.0 condition of normally working through this kind of mode.

In order to solve the above problems, the utility model adopts the following technical proposal:

a clamp for verifying influence of capacitance difference of a USB3.0AC coupling capacitor on an eye diagram comprises a PCB, wherein a first TX + input end, a first TX-input end, a first TX + output end, a first TX-output end, a second TX + input end, a second TX-input end, a second TX + output end, a second TX-output end, a third TX + input end, a third TX-input end, a third TX + output end and a third TX-output end are arranged on the PCB, the first TX + input end is connected with the first TX + output end through a first transmission line, the first TX-input end is connected with the first TX-output end through a second transmission line, the second TX + input end is connected with the second TX + output end through a third transmission line, the second TX-input end is connected with the second TX-output end through a fourth transmission line, the third TX + input end is connected with the third TX + output end through a fifth transmission line, the third TX-input end is connected with the third TX-output end through a sixth transmission line, a capacitor C1 is connected in series on the first transmission line, a capacitor C2 is connected in series on the second transmission line, a capacitor C3 is connected in series on the third transmission line, a capacitor C4 is connected in series on the fourth transmission line, a capacitor C5 is connected in series on the fifth transmission line, and a capacitor C6 is connected in series on the sixth transmission line.

According to a further technical scheme, the first TX + input end, the first TX-input end, the first TX + output end, the first TX-output end, the second TX + input end, the second TX-input end, the second TX + output end, the second TX-output end, the third TX + input end, the third TX-input end, the third TX + output end and the third TX-output end are all 3.5mm SMA female head seats.

Adopt the produced beneficial effect of above-mentioned technical scheme to lie in: the influence on the USB3.0 eye diagram is observed by changing the capacitance value of the USB3.0AC coupling capacitor, whether the USB3.0 can normally work can be verified by the mode, the number of devices used by the clamp is small, the clamp is convenient to manufacture, the cost of all devices does not exceed 50 yuan, the cost is low, and the cost performance is very high.

Drawings

Fig. 1 is a schematic diagram of the present invention.

In the figure: 1. a PCB board; 2. a first TX + input; 3. a first TX-input; 4. a first TX + output; 5. a first TX output; 6. a second TX + input; 7. a second TX-input; 8. a second TX + output; 9. a second TX-output; 10. a third TX + input; 11. a third TX-input; 12. a third TX + output; 13. a third TX output; 14. a first transmission line; 15. a second transmission line; 16. a third transmission line; 17. a fourth transmission line; 18. a fifth transmission line; 19. a sixth transmission line.

Detailed Description

The following describes embodiments of the present invention in further detail with reference to the accompanying drawings and examples. The following examples are intended to illustrate the invention, but are not intended to limit the scope of the invention.

As shown in FIG. 1, a clamp for verifying that USB3.0AC coupling capacitance difference affects eye diagram comprises a PCB board 1, the PCB board 1 is provided with a first TX + input end 2, a first TX-input end 3, a first TX + output end 4, a first TX-output end 5, a second TX + input end 6, a second TX-input end 7, a second TX + output end 8, a second TX-output end 9, a third TX + input end 10, a third TX-input end 11, a third TX + output end 12 and a third TX-output end 13, the first TX + input end 2 is connected with the first TX + output end 4 through a first transmission line 14, the first TX-input end 3 is connected with the first TX-output end 5 through a second transmission line 15, the second TX + input end 6 is connected with the second TX + output end 8 through a third transmission line 16, the second TX-input end 7 is connected to the second TX-output end 9 through a fourth transmission line 17, the third TX + input end 10 is connected to the third TX + output end 12 through a fifth transmission line 18, the third TX-input end 11 is connected to the third TX-output end 13 through a sixth transmission line 19, a capacitor C1 is connected in series to the first transmission line 14, a capacitor C2 is connected in series to the second transmission line 15, a capacitor C3 is connected in series to the third transmission line 16, a capacitor C4 is connected in series to the fourth transmission line 17, a capacitor C5 is connected in series to the fifth transmission line 18, and a capacitor C6 is connected in series to the sixth transmission line 19.

The first TX + input end 2, the first TX-input end 3, the first TX + output end 4, the first TX-output end 5, the second TX + input end 6, the second TX-input end 7, the second TX + output end 8, the second TX-output end 9, the third TX + input end 10, the third TX-input end 11, the third TX + output end 12 and the third TX-output end 13 are all 3.5mm SMA female head seats.

The working principle is as follows: the first TX + input end 2, the first TX-input end 3, the second TX + input end 6, the second TX-input end 7, the third TX + input end 10 and the third TX-input end 11 are signal input ends, the USB3.0 signal source is connected through the SMA cable, the first transmission line 14, the second transmission line 15, the third transmission line 16, the fourth transmission line 17, the fifth transmission line 18 and the sixth transmission line 19 are three pairs of differential transmission line pairs, capacitors C1 and C2 which are serially connected between the first transmission line 14 and the second transmission line 15 are 1uf, capacitors C3 and C4 which are serially connected between the third transmission line 16 and the fourth transmission line 17 are 100uf, capacitors C5 and C6 which are serially connected between the fifth transmission line 18 and the sixth transmission line 19 are 1000uf, and three pairs of SMA female head seats (a first TX + output end 4, a first TX-output end 5, a second TX + output end 8) on the right side of the PCB board 1 are provided with the first TX + output end 4, the second TX-input end 4 and the second TX-output end 8, A second TX-output end 9, a third TX + output end 12 and a third TX-output end 13) as output ends, and the output ends are connected to an oscilloscope through an SMA cable to output USB3.0 differential signals TX + and TX-signals.

When the clamp is used for testing, a USB3.0 signal source is connected to a first TX + input end 2 and a first TX-input end 3 on a clamp plate through an SMA cable, signals are transmitted through a pair of differential transmission lines of a first transmission line 14 and a second transmission line 15, capacitors C1 and C2 connected in series between the first transmission line 14 and the second transmission line 15 are 1uf, the differential signals output by the output end are sent to an oscilloscope at the moment, an eye diagram at the moment is observed, when the capacitance value of an AC coupling capacitor is 1uf, the USB3.0 eye diagram is good, read-write verification of a USB flash disk is carried out, and the function is normal. And then connecting a USB3.0 signal source to a second TX + input end 6 and a second TX-input end 7 on the clamp plate through an SMA cable, transmitting signals through a pair of differential transmission lines of a third transmission line 16 and a fourth transmission line 17, wherein the capacitors C3 and C4 connected in series between the third transmission line 16 and the fourth transmission line 17 are 100uf, transmitting the differential signals output by the output end to an oscilloscope, observing an eye diagram at the moment, and when the capacitance value of the AC coupling capacitor is 100uf, the USB3.0 eye diagram is deteriorated but still meets the specification requirement, performing read-write verification on the USB flash disk again, and the function is still normal. Finally, a USB3.0 signal source is connected to a third TX + input end 10 and a third TX-input end 11 on a clamp plate through an SMA cable, signals are transmitted through a pair of differential transmission lines, namely a fifth transmission line 18 and a sixth transmission line 19, capacitors C5 and C6 connected in series between the fifth transmission line 18 and the sixth transmission line 19 are 1000uf, the differential signals output by an output end are sent to an oscilloscope, the eye diagram at the moment is observed, when the capacitance value of the AC coupling capacitor is 1000uf, the USB3.0 eye diagram is closed, the USB3.0 eye diagram is read and written again, the U disk is verified, the functions cannot be identified and are invalid, the influence on the USB3.0 eye diagram is observed by changing the capacitance value of the USB3.0AC coupling capacitor, whether the USB3.0 can work normally or not can be verified in this way, and the verification shows that the larger the capacitance value is, the more serious influence on the USB3.0 eye diagram is, and the function loss can also be caused.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the embodiments of the present invention.

Claims (2)

1. A clamp for verifying that USB3.0AC coupling capacitance value difference affects an eye pattern is characterized in that: comprises a PCB (1), wherein a first TX + input end (2), a first TX-input end (3), a first TX + output end (4), a first TX-output end (5), a second TX + input end (6), a second TX-input end (7), a second TX + output end (8), a second TX-output end (9), a third TX + input end (10), a third TX-input end (11), a third TX + output end (12) and a third TX-output end (13) are arranged on the PCB (1), the first TX + input end (2) is connected with the first TX + output end (4) through a first transmission line (14), the first TX-input end (3) is connected with the first TX-output end (5) through a second transmission line (15), the second TX + input end (6) is connected with the second TX + output end (8) through a third transmission line (16), the second TX-input end (7) is connected with a second TX-output end (9) through a fourth transmission line (17), the third TX + input end (10) is connected with a third TX + output end (12) through a fifth transmission line (18), the third TX-input end (11) is connected with a third TX-output end (13) through a sixth transmission line (19), a capacitor C1 is connected in series on the first transmission line (14), a capacitor C2 is connected in series on the second transmission line (15), a capacitor C3 is connected in series on the third transmission line (16), a capacitor C4 is connected in series on the fourth transmission line (17), a capacitor C5 is connected in series on the fifth transmission line (18), and a capacitor C6 is connected in series on the sixth transmission line (19).

2. The fixture for verifying that the difference of the capacitance values of the USB3.0AC coupling capacitors affects the eye diagram according to claim 1, wherein: the first TX + input end (2), the first TX-input end (3), the first TX + output end (4), the first TX-output end (5), the second TX + input end (6), the second TX-input end (7), the second TX + output end (8), the second TX-output end (9), the third TX + input end (10), the third TX-input end (11), the third TX + output end (12) and the third TX-output end (13) are all 3.5mm SMA female head seats.

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