USB downstream port performance test system and test method

Abstract

The application provides a USB downstream port performance test system and a test method. The USB downstream port performance test system comprises test software and a test fixture. The test software is configured in an upper computer, and the test fixture is connected to the upper computer through a device under test. The test software sends a test instruction to the test fixture through the device under test, so as to test the communication rate, the load capacity, the output overload protection function, the output short circuit protection function of the USB downstream port of the device under test, and whether the IO exists an open circuit or a short circuit phenomenon. The USB downstream port performance of the device under test is tested in an automatic mode, the operation is simple, the test efficiency is high, the test result is more accurate, and the manpower cost can be greatly saved.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of USB port performance testing, and particularly relates to a USB downstream port performance testing system and a testing method. BACKGROUND

[0002] The USB interface is one of the most popular data transmission interfaces at present. Through the USB interface, a hard disk, a U disk, a USB sound card, a USB graphics card, a USB network card, a USB card reader, a USB interface printer, a two-dimensional code scanner, a mobile phone, a tablet computer and other devices that can be used or seen by ordinary users can be connected. In industrial application intelligence, data exchange can also be performed through the USB interface, an RS232 interface and an RS485 interface. With the wide popularity of the USB interface, more and more USB devices appear on the market, and there are often multiple USB devices in a family. The reason why the USB interface is so popular is that it has a built-in USB2.0 and USB3.0 data channel, and supports a very wide data transmission rate, which can be automatically adapted to low speed, high speed and ultra-high speed. In addition, the USB interface also has a power supply function, so that the power adapter of the external device can be saved.

[0003] In order to support a higher data transmission rate and also to stably transmit signals by using a relatively long cable, each group of data lines of the USB interface adopts a differential line form, that is, each group of signals is transmitted by using two data lines, and the phases of the two data lines are opposite. The differential line can improve the anti-interference performance and realize long-distance transmission under high-speed communication. However, if one of the data lines in the differential line is short-circuited with other IO due to poor production process, virtual welding or poor contact, etc., it is often difficult to be found. Because many USB devices are designed to be differential lines in order to improve compatibility, even if one of the data lines is disconnected, some USB devices can still work, but the transmission length or speed supported will be reduced.

[0004] In addition, the USB downstream port has a power supply function. The power supply has different output capacities, for example, 500mA for USB2.0, 900mA for USB3.0, 1.5A for USB3.1, or Apple2.4A and SAMSUNG 2A for compatibility with more charging specifications. In addition, the USB downstream port generally has requirements for the output voltage under load, and requires short-circuit protection, over-current protection and abnormal reporting of the power output. Therefore, in order to ensure that the functions and performances of the USB interface of the product output are normal, it is necessary to test the functions and performances of the USB interface as follows:

[0005] The Full Speed communication test is performed on the USB 2.0 device, the Full Speed communication adopts a 3.3V Vp-p level format, and the highest rate is 12 Mbps; the Hi Speed communication test is performed on the USB 2.0 device, the Hi Speed communication adopts a 500mV Vp-p level format, and the highest rate is 480 Mbps; the Gen1 5G communication test is performed on the USB 3.0 device, the Gen1 5G communication adopts another two pairs of differential pairs except the USB 2.0 differential pair for transmission, adopts a 500mV Vp-p level format, and the highest rate is 5Gbps; the Gen2 10G communication test is performed on the USB 3.0 device, the Gen2 10G communication adopts another two pairs of differential pairs except the USB 2.0 differential pair for transmission, adopts a 500mV Vp-p level format, and the highest rate is 10Gbps; the load test of the power supply circuit is performed, the electrical load absorbs a specified current value, and whether the output voltage is in a normal range is measured; the protection function test of the power supply circuit is performed to test whether the overcurrent and short-circuit protection functions of the USB downstream port are normal; whether the three pairs of differential lines in the USB 2.0 and the USB 3.0 exist open circuit and short circuit is tested.

[0006] However, at present, the above tests are all tested by artificial item by item, the test time is long, the labor cost is high, and errors are easy to occur. In particular, when the IO of the USB interface appears short circuit and open circuit, it is difficult to find and measure. SUMMARY

[0007] In order to at least partially overcome the problems in the related art, the present application provides a USB downstream port performance test system and a test method.

[0008] According to a first aspect of the embodiments of the present application, the present application provides a USB downstream port performance test system, which comprises test software and a test fixture; the test software is configured in an upper computer, and the test fixture is connected with the upper computer through a device under test; the test software sends a test instruction to the test fixture through the device under test, so as to test the communication rate, the load capacity, the output overload protection function, the output short-circuit protection function of the USB downstream port of the device under test, and whether the IO exists open circuit and short circuit.

[0009] In the USB downstream port performance test system, the test software comprises a product database, a test fixture database, a test history database and a main program;

[0010] The product database is used for storing characteristic parameters, measurement time, measurement duration and judgment range values of products, so as to adapt to the test requirements of different products;

[0011] The test fixture database is used to store the functions, capabilities and test instruction sets of the test fixture to adapt to the tests of different devices under test;

[0012] The test history database is used to save the product models, serial numbers, PIDs, VIDs, original measurement data, test time points and determination results of recently tested products for users to trace back and export;

[0013] The main program is used to import a test file and read and write the test file through the device under test to test the read and write rates; the main program is also used to detect the signals of the device under test to call the corresponding test parameters in the product database to complete the test of the device under test; the main program is also used to obtain a model of a product manually selected by a user and test the product according to the test parameters of the product corresponding to the model in the product database.

[0014] Further, the main program is also used to call a third-party hard disk speed testing tool to test the read and write rates of the USB downstream port of the device under test.

[0015] Further, the main program is used to push the test results to a comprehensive test result interface, and the comprehensive test result interface displays the comprehensive test results, which are OK or NG; when the comprehensive test result is NG, the interface also displays the test results and original test data of each sub-test item.

[0016] Further, the test fixture includes a HUB, a first selection switch, a USB high-speed hard disk, an MCU, an IO online measurement circuit, a second selection switch, a programmable electronic load and a farad capacitor module.

[0017] The upstream interface of the HUB is connected with a USB bus through the first selection switch, and the USB bus is connected with the USB downstream port of the device under test; the downstream interface of the HUB is connected with the USB high-speed hard disk.

[0018] The MCU is connected with the host computer through a power line, a USB bus and the device under test in sequence, and the host computer supplies power to the MCU through the device under test;

[0019] The MCU is connected with the HUB and the first selection switch, and the MCU controls the first selection switch to select the connection with the IO online measurement circuit or the HUB;

[0020] The MCU is connected with the USB high-speed hard disk or the programmable electronic load through the second selection switch to select the connection with the USB high-speed hard disk or the programmable electronic load through the second selection switch, and supply power to the USB high-speed hard disk or the programmable electronic load;

[0021] The farad capacitor module includes a voltage step-down circuit and a farad capacitor, an input end of the voltage step-down circuit is connected with a power supply, an output end of the voltage step-down circuit is connected with the MCU and a positive pole of the farad capacitor, and a negative pole of the farad capacitor is grounded; the power supply on the power line charges the farad capacitor module, and when the MCU performs a power over-current protection test or a power short-circuit protection test, the farad capacitor supplies power for the MCU.

[0022] Further, the programmable electronic load is used for absorbing different currents from the power line according to different current setting instructions sent by the MCU, and is also used for short-circuiting the power line to GND according to a short-circuit instruction sent by the MCU.

[0023] Further, the IO online measurement circuit includes a first measurement switch, a negative voltage constant current source, a second measurement switch and a voltage holding circuit.

[0024] One end of the first measurement switch is connected with a USB downstream port of the device under test through the first selection switch and a USB bus, and the other end of the first measurement switch is connected with the negative voltage constant current source; the negative voltage constant current source is connected with a power supply in the device under test through the USB bus; the other end of the first measurement switch is also connected with the voltage holding circuit through the second measurement switch, and the voltage holding circuit is connected with the MCU.

[0025] The MCU is connected with the first measurement switch and the second measurement switch, and is used for controlling the first measurement switch to select the connection of which data line in the USB downstream port to be turned on, and is also used for controlling the second measurement switch to be turned on or turned off.

[0026] Further, the process of the MCU controlling the IO online measurement circuit to perform online measurement is as follows:

[0027] The MCU selects the current IO under test by controlling the first measurement switch, and then the MCU controls the second measurement switch to be started to sample a negative voltage value of the current selected channel; the negative voltage value is input into the MCU through the voltage holding circuit.

[0028] The MCU enables an internal analog-digital conversion circuit ADC to perform analog-digital conversion on the received negative voltage value, so as to obtain a voltage value of the current IO under test under the negative voltage constant current source.

[0029] The above two steps are repeatedly performed to complete the measurement of all IOs in the IO online measurement circuit.

[0030] The MCU returns the voltage values of all the IOs under the constant current source of the negative pressure to the test software, so that the test software judges whether there is an open circuit or a short circuit according to the reverse voltage values of the IOs.

[0031] According to a second aspect of the embodiments of the present application, the present application further provides a USB downstream port performance testing method, which comprises the following steps:

[0032] setting the test USB downstream port performance testing system described in any of the above;

[0033] The test software imports a USB downstream port measurement parameter setting normal range setting table into a product database; the USB downstream port measurement parameter setting normal range setting table comprises a model, a parameter category, a parameter setting, and a discrimination range;

[0034] The test software discriminates whether a device under test is connected by querying a PID, a VID, and a serial number of the connected USB device;

[0035] If the device under test is connected, the test software sends a test condition to a test fixture according to a test parameter in the imported USB downstream port measurement parameter setting normal range setting table;

[0036] The test fixture tests the USB downstream port performance according to the test condition, and feeds back a test result to the test software; the test software compares the received test result with a related parameter in the USB downstream port measurement parameter setting normal range setting table, to determine whether each test item of the USB downstream port is qualified.

[0037] In the USB downstream port performance testing method, the test fixture tests the USB downstream port performance according to the test condition, and feeds back the test result to the test software; the test software compares the received test result with the related parameter in the USB downstream port measurement parameter setting normal range setting table, to determine whether each test item of the USB downstream port is qualified.

[0038] The test software reads and writes a large file block to a USB high-speed hard disk connected to a USB downstream port of the device under test, to determine whether a communication rate of the USB downstream port of the device under test is qualified;

[0039] The test software writes a "normal load characteristic test" instruction to a programmable electronic load inside the test fixture connected to the USB downstream port of the device under test, and reads back a voltage value of the USB interface at this time through the test fixture, to determine whether a load capacity of the USB downstream port of the device under test is qualified;

[0040] The test software writes the instruction of "over-current protection test" to the programmable electronic load inside the test fixture connected to the USB downstream port of the device under test, and reads back the measured parameters of the USB interface during the protection period through the test fixture, and compares the measured parameters with the set parameters in the database to determine whether the output overload protection function of the USB downstream port of the device under test is qualified.

[0041] The test software writes the instruction of "short-circuit protection test" to the programmable electronic load inside the test fixture connected to the USB downstream port of the device under test, and reads back the measured parameters of the USB interface during the protection period through the test fixture, and compares the measured parameters with the set parameters in the database to determine whether the output short-circuit protection function of the USB downstream port of the device under test is qualified.

[0042] The test software initiates the "IO open-circuit short-circuit test" test to the IO open-circuit short-circuit test circuit inside the test fixture connected to the USB downstream port of the device under test, and reads back the measured voltage readings of each IO through the test fixture, and compares the measured voltage readings with the set parameters in the database to determine whether the IO of the USB downstream port of the device under test has open-circuit or short-circuit phenomenon.

[0043] According to the above specific embodiments of the present application, at least the following beneficial effects are obtained: the USB downstream port performance test system provided by the present application sets the test software in the host computer and the test fixture connected to the host computer through the device under test; the test software sends test instructions to the test fixture through the device under test to test the communication rate, load capacity, output overload protection function, output short-circuit protection function of the USB downstream port of the device under test, and whether the IO has open-circuit or short-circuit phenomenon; the present application tests the USB downstream port performance of the device under test in an automatic manner, which is simple to operate, high in testing efficiency, more accurate in testing results, and can greatly save labor cost.

[0044] It should be understood that the above general description and the following specific embodiments are only exemplary and explanatory, and cannot limit the scope of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0045] The following accompanying drawings are part of the specification of the present application, which show the embodiments of the present application, and together with the description of the specification, illustrate the principles of the present application.

[0046] Figure 1 A structure schematic diagram of a USB downstream port performance test system provided by an embodiment of the present application.

[0047] Figure 2 A connection relationship schematic diagram of an IO online measurement circuit in a USB downstream port performance test system provided by an embodiment of the present application, a device under test, an MCU and a HUB.

[0048] BRIEF DESCRIPTION OF DRAWINGS

[0049] 1. test software;

[0050] 2. test fixture;

[0051] 21. HUB; 22. first selection switch; 23. USB high-speed hard disk; 24. MCU;

[0052] 25. IO online measurement circuit; 251. first measurement switch; 252. negative voltage constant current source; 253. second measurement switch; 254. voltage holding circuit;

[0053] 26. second selection switch; 27. programmable electronic load; 28. farad capacitor module;

[0054] 10. host computer;

[0055] 20. device under test. DETAILED DESCRIPTION

[0056] In order to make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the following will clearly explain the spirit of the present application with the aid of the drawings and detailed description. Any person skilled in the art, after understanding the embodiments of the present application, can make changes and modifications to the technology taught by the present application without departing from the spirit and scope of the present application.

[0057] The illustrative embodiments of the present application and their descriptions are used to explain the present application, but are not used as limitations of the present application. In addition, the same or similar elements / components in the drawings and embodiments are used to represent the same or similar parts.

[0058] As for the "first", "second", and the like used herein, they are not intended to particularly refer to the order or sequence, nor to limit the present application. They are merely used to distinguish elements or operations described by the same technical terms.

[0059] As for the "include", "comprise", "have", "contain", and the like used herein, they are all open terms, i.e., meaning to include but not limited to.

[0060] As for the "and / or" used herein, it includes any or all combinations of the described things.

[0061] As for the "multiple" herein, it includes "two" and "more than two"; as for the "multiple groups" herein, it includes "two groups" and "more than two groups".

[0062] Certain terms used to describe this application will be discussed below or elsewhere in this specification to provide additional guidance to those skilled in the art in describing the application.

[0063] like Figure 1 As shown, the USB downstream port performance testing system provided in this application includes testing software 1 and testing fixture 2. The testing software 1 can be configured in the host computer 10, and the testing fixture 2 is connected to the host computer 10 through the device under test 20. The testing software 1 sends test commands to the testing fixture 2 through the device under test 20 to test the communication rate, load capacity, output overload protection function, output short circuit protection function, and whether there are open circuits or short circuits in the USB downstream port of the device under test 20.

[0064] In this embodiment, the testing software 1 includes a product database, a test fixture database, a test history database, and a main program. The product database stores product characteristic parameters, measurement timing, measurement duration, and judgment range values ​​to adapt to the testing needs of different products. The test fixture database stores characteristic parameters such as the functions, capabilities, and test instruction sets of the test fixture 2 to facilitate testing of different devices under test (DUTs) 20. The test history database saves the recently tested product model, serial number, PID (Product Identification Code), VID (Supplier ID), original measurement data, test time points, and judgment results for user traceability and export. The main program imports test files and reads and writes these test files to the test fixture 2 via the DUT 20 to test read / write speeds. The main program also detects signals from the DUT 20 to retrieve corresponding test parameters from the product database to complete the testing of the DUT 20. Furthermore, the main program can obtain the model of a product manually selected by the user and test the product according to the test parameters in the corresponding product database.

[0065] In addition, the main program can also call third-party hard drive speed testing tools to test the read and write speed of the USB downstream port of the device under test 20.

[0066] After the test is completed, the main program pushes the test results to the comprehensive test results interface, which will display the comprehensive test result, such as OK or NG. If the comprehensive test result is NG, the test results and raw test data of each sub-test item will also be displayed, so that users can understand which test item failed and what the measured value was. Regardless of whether the comprehensive test result is OK or NG, the tested product model, serial number, PID, VID, raw measurement data, test time point, and judgment result will be written to the historical database for users to trace and export.

[0067] In the embodiment, the test fixture 2 is used to receive high-speed data read-write of the test software 1 and is used to receive instructions sent by the test software 1 to perform normal load test, over-current protection test and short-circuit protection test of the USB power supply; the test fixture 2 is also used to report current, voltage and time parameters on the current power supply line to the test software 1 through the device under test 20, so that the test software 1 determines whether the USB data transmission of the device under test 20 is normal and whether the power supply circuit is normal, IO has open circuit or short circuit fault and the like according to the voltage, current and time parameters.

[0068] Specifically, as shown in the figure, Figure 2 The test fixture 2 includes a HUB 21, a first selection switch 22, a USB high-speed hard disk 23, an MCU 24, an IO online measurement circuit 25, a second selection switch 26, a programmable electronic load 27 and a farad capacitor module 28.

[0069] The uplink interface of the HUB 21 is connected with the USB bus through the first selection switch 22, and the USB bus is connected with the USB downlink port of the device under test 20; the downlink interface of the HUB 21 is connected with the USB high-speed hard disk 23.

[0070] The MCU 24 is connected with the host computer 10 through the power supply line, the USB bus and the device under test 20 in sequence, and the host computer 10 supplies power for the MCU 24 through the device under test 20.

[0071] The MCU 24 is connected with the HUB 21 and the first selection switch 22, and the MCU 24 controls the first selection switch 22 to select the connection with the IO online measurement circuit 25 or the HUB 21.

[0072] When the MCU 24 controls the first selection switch 22 to select the connection with the HUB 21, the HUB 21 collects the test instructions of the test software 1 and sends the collected test instructions to the MCU 24; the MCU 24 uploads the test data to the test software 1 through the HUB 21, the first selection switch 22, the USB bus and the device under test 20 in sequence, so that the test software 1 completes the collection of the test data.

[0073] When the MCU 24 controls the first selection switch 22 to select the connection with the IO online measurement circuit 25, the IO online measurement circuit 25 sends the measured voltage value to the MCU 24, and the MCU 24 returns the voltage value of the IO to the test software 1 through the HUB 21, the first selection switch 22, the USB bus and the device under test 20 in sequence, so that the test software 1 determines whether there is an open circuit or a short circuit condition according to the voltage value of the IO.

[0074] MCU 24 is connected with USB high-speed hard disk 23 or programmable electronic load 27 through second selection switch 26, so as to select the connection of USB high-speed hard disk 23 or programmable electronic load 27 through second selection switch 26, thereby supplying power for USB high-speed hard disk 23 or programmable electronic load 27. When MCU 24 supplies power for programmable electronic load 27 through second selection switch 26, MCU 24 is also used for controlling programmable electronic load 27 to carry out normal load test, over-current protection test and short-circuit protection test of power supply and the like.

[0075] Among them, programmable electronic load 27 can absorb relatively high power in a short time, for example, 5V*4A=20W; it can also support short circuit between power supply line and GND. Specifically, programmable electronic load 27 can absorb different currents from the power supply line according to different current setting instructions sent by MCU 24, and can also short circuit the power supply line to GND according to the short circuit instruction sent by MCU 24.

[0076] Farad capacitor module 28 includes voltage step-down circuit and farad capacitor, wherein the input end of voltage step-down circuit is connected with power supply, the output end of voltage step-down circuit is connected with MCU 24, and the output end of voltage step-down circuit is connected with the positive electrode of farad capacitor, and the negative electrode of farad capacitor is grounded. The power supply on the power supply line charges farad capacitor module 28. When MCU 24 executes over-current protection test or short-circuit protection test of power supply, the power supply on USB bus will be lost due to the protection function of device under test 20 being started, at this time, farad capacitor discharges, and farad capacitor supplies power for MCU 24, so as to ensure the execution of over-current protection test or short-circuit protection test of power supply.

[0077] In the above embodiment, IO online measurement circuit 25 includes first measurement switch 251, negative voltage constant current source 252, second measurement switch 253 and voltage holding circuit 254. Wherein one end of first measurement switch 251 is connected with USB downstream port of device under test 20 through first selection switch 22 and USB bus, the other end of first measurement switch 251 is connected with negative voltage constant current source 252, negative voltage constant current source 252 is connected with power supply in device under test 20 through USB bus. The other end of first measurement switch 251 is also connected with voltage holding circuit 254 through second measurement switch 253, voltage holding circuit 254 is connected with MCU 24. MCU 24 is connected with first measurement switch 251 and second measurement switch 253, and is used for controlling first measurement switch 251 to select the connection of which data line in USB downstream port to be turned on, and is also used for controlling second measurement switch 253 to be turned on or turned off.

[0078] IO online measurement circuit 25 is different from conventional measurement method, and the conventional measurement method is as follows:

[0079] Measure whether the IO is open circuit: the two probes of the ohmmeter are placed at the source end of the IO and the interface end of the IO respectively.

[0080] Measure whether a certain IO is short-circuited with other IOs, GND, VBUS, etc. The measurement of whether the measured IO is short-circuited with other IOs needs to be measured separately, and the number of measurements is large and the test time is relatively long. For short-circuit measurement, any IO needs to be measured with the other 5 IOs inside USB3.0, GND, and VBUS, which is equivalent to 7 measurements. All IO tests need 27 measurements (7+6+5+4+3+2=27), which is very time-consuming. If only the reverse current between the measured IO and GND is measured to determine whether the IO is short-circuited with other IOs, GND, and VBUS, the measurement speed can be greatly improved, and only 6 measurements are needed to determine the voltage generated by the constant current source on the current measured IO.

[0081] In order to realize fast testing and simplify the complex circuit of sampling the source end of the IO during open circuit testing, the following method is used:

[0082] The sampling point of the source end of the IO test is unified to GND. The reason for this is that the reverse breakdown voltage of the ESD protection diode between the IO of a certain specified model and GND is fixed in a certain fixed range, so this feature can be used to simplify the sampling of the source end during IO open circuit testing. The pin8 and pin9 of the USB3.0 downstream port are capacitively isolated, and if a DC voltage source is used to test between them and GND, it will be in an open circuit state, but we can use the principle that the voltage across a capacitor cannot change abruptly to make a transient test to achieve the above-mentioned IO open circuit test.

[0083] The process of the MCU24 controlling the IO online measurement circuit 25 to perform online measurement is as follows:

[0084] The MCU24 selects the current measured IO by controlling the first measurement switch 251, and then the MCU24 controls the second measurement switch 253 to start sampling the negative voltage value of the current selected channel. The negative voltage value is input into the MCU24 through the voltage holding circuit 254. The magnitude of the negative voltage value mainly depends on the forward voltage V F of the ESD protection diode on the GND side of the current IO under the current forward current I F .

[0085] MCU 24 enables internal high-resolution analog-to-digital conversion circuit ADC to analog-to-digital convert the received negative voltage value, to obtain the accurate voltage value of the current measured IO under the negative voltage constant current source 252.

[0086] The above two steps are repeated to complete the measurement of all measured IOs in the IO online measurement circuit 25.

[0087] MCU 24 returns the measured voltage value of all IOs under the negative voltage constant current source 252 to the test software 1, so that the test software 1 judges whether there is an open circuit or a short circuit according to the reverse voltage value of each IO.

[0088] Based on the USB downstream port performance test system provided in the present application, the present application further provides a USB downstream port performance test method, which comprises the following steps:

[0089] S1, the test software 1 imports the USB downstream port measurement parameter setting normal range setting table into the product database.

[0090] S2, the test software 1 judges whether there is a measured device 20 connected by querying the PID, VID and serial number of the connected USB device.

[0091] S3, if there is a measured device 20 connected, the test software 1 sends the test conditions to the test fixture 2 according to the test parameters in the imported USB downstream port measurement parameter setting normal range setting table.

[0092] S4, the test fixture 2 tests the USB downstream port performance according to the test conditions, and feeds back the test results to the test software 1, and the test software 1 compares the received test results with the related parameters in the USB downstream port measurement parameter setting normal range setting table to determine whether each test item of the USB downstream port is qualified; the specific process is:

[0093] The test software 1 reads and writes large file blocks to the USB high-speed hard disk 23 connected to the USB downstream port of the measured device 20, to determine whether the communication rate of the USB downstream port of the measured device 20 is qualified.

[0094] The test software 1 writes the instruction of "normal load characteristic test" to the programmable electronic load 27 inside the test fixture 2 connected to the USB downstream port of the measured device 20, and reads back the voltage value of the USB interface at this time through the test fixture 2, to determine whether the load capacity of the USB downstream port of the measured device 20 is qualified.

[0095] The test software 1 writes the instruction of "over-current protection test" to the programmable electronic load 27 inside the test fixture 2 connected to the USB downstream port of the device under test 20, and reads back the measured parameters of the USB interface during the protection period, such as voltage, current, hiccup duration, hiccup time interval, etc., and compares them with the set parameters in the database to determine whether the output overload protection function of the USB downstream port of the device under test 20 is qualified.

[0096] The test software 1 writes the instruction of "short-circuit protection test" to the programmable electronic load 27 inside the test fixture 2 connected to the USB downstream port of the device under test 20, and reads back the measured parameters of the USB interface during the protection period, such as voltage, current, hiccup duration, hiccup time interval, etc., and compares them with the set parameters in the database to determine whether the output short-circuit protection function of the USB downstream port of the device under test 20 is qualified.

[0097] The test software 1 initiates the "IO open / short circuit test" test to the IO open / short circuit test circuit inside the test fixture 2 connected to the USB downstream port of the device under test 20, and reads back the measured voltage readings of each IO, and compares them with the set parameters in the database to determine whether the IO of the USB downstream port of the device under test 20 has open / short circuit phenomenon.

[0098] In the above step S1, the USB downstream port measurement parameter setting is set to a normal range setting master table including model, parameter category, parameter setting and its judgment range. Among them, the parameter category includes product identification, read-write speed, VBUS maximum and minimum no-load voltage, VBUS normal load current and VBUS maximum and minimum normal load voltage, VBUS over-current parameter, VBUS short-circuit parameter, IO open / short circuit judgment parameter and the model of the test fixture 2.

[0099] The product identification in the product identification includes a product PID and a product VID. The read-write rate includes a USB 2.0 minimum write rate, a USB 2.0 minimum read rate, a USB 3.0 minimum write rate, and a USB 3.0 minimum read rate. The VBUS over-current parameter includes minimum and maximum maintenance currents when VBUS over-current is not hiccup, minimum and maximum voltages when VBUS over-current is hiccup, minimum and maximum time lengths when VBUS over-current is hiccup, minimum and maximum interval time lengths when VBUS over-current is hiccup. The VBUS short-circuit parameter includes a VBUS short-circuit resistance, whether to hiccup when VBUS short-circuit, whether to lock when VBUS short-circuit, minimum and maximum maintenance currents when VBUS short-circuit is not hiccup, maximum voltage when VBUS short-circuit is hiccup, minimum and maximum time lengths when VBUS short-circuit is hiccup, minimum and maximum interval time lengths when VBUS short-circuit is hiccup. The IO open-circuit or short-circuit determination parameter includes a USB 2.0 IO reverse minimum voltage, a USB 2.0 reverse maximum voltage, a USB 3.0 IO reverse minimum voltage, and a USB 3.0 reverse maximum voltage.

[0100] It should be noted that the USB downstream port performance test method provided by the above embodiment and the USB downstream port performance test system embodiment belong to the same concept, and the specific implementation process is detailed in the system embodiment, which will not be repeated here.

[0101] In the example embodiment, the embodiment of the application also provides a computer storage medium, which is a computer readable storage medium, for example, a memory including a computer program, and the computer program can be executed by a processor to complete the USB downstream port performance test method in any one of the embodiments of the application.

[0102] The above embodiments of the application can be implemented in various hardware, software coding or combination of both. For example, the embodiments of the application can also represent program codes executed in a data signal processor to perform the above method. The application can also relate to various functions performed by a computer processor, a digital signal processor, a microprocessor or a field programmable gate array. The above processor can be configured according to the application to perform specific tasks, which are completed by executing machine-readable software codes or firmware codes defining specific methods disclosed by the application. The software codes or firmware codes can be developed to represent different program languages and different formats or forms. The software codes can also be compiled for different target platforms. However, the software codes performing tasks according to the application and other types of configuration codes of different code styles, types and languages do not deviate from the spirit and scope of the application.

[0103] The above description is only a specific implementation of the application, and any equivalent changes and modifications made by those skilled in the art without departing from the concept and principles of the application shall fall within the scope of protection of the application.

Claims

1. A USB downstream port performance test system, characterized in that, The test software is configured in a host computer, and the test fixture is connected with the host computer through a device under test; the test software sends a test instruction to the test fixture through the device under test, so as to test a communication rate, a load capacity, an output overload protection function, an output short circuit protection function and whether there is an open circuit or a short circuit phenomenon of a USB downstream port of the device under test; The test fixture comprises a HUB, a first selection switch, a USB high-speed hard disk, an MCU, an IO online measurement circuit, a second selection switch, a programmable electronic load and a farad capacitor module; An upstream interface of the HUB is connected with a USB bus through the first selection switch, and the USB bus is connected with a USB downstream port of the device under test; a downstream interface of the HUB is connected with the USB high-speed hard disk; The MCU is connected with the host computer through a power supply line, a USB bus and the device under test in sequence, and the host computer supplies power for the MCU through the device under test; The MCU is connected with the HUB and the first selection switch, and the MCU controls the first selection switch to select a connection with the IO online measurement circuit or the HUB; The MCU is connected with the USB high-speed hard disk or the programmable electronic load through the second selection switch, so as to select a connection with the USB high-speed hard disk or the programmable electronic load through the second selection switch, supply power for the USB high-speed hard disk or the programmable electronic load; The farad capacitor module comprises a voltage step-down circuit and a farad capacitor, an input end of the voltage step-down circuit is connected with a power supply, an output end of the voltage step-down circuit is connected with the MCU and a positive pole of the farad capacitor, and a negative pole of the farad capacitor is grounded; power supply on the power supply line charges the farad capacitor module, and the farad capacitor supplies power for the MCU when the MCU performs a power overcurrent protection test or a power short circuit protection test; The programmable electronic load is used for absorbing different currents from the power supply line according to different current setting instructions sent by the MCU, and is also used for short-circuiting the power supply line to GND according to a short circuit instruction sent by the MCU; The IO online measurement circuit comprises a first measurement switch, a negative voltage constant current source, a second measurement switch and a voltage holding circuit; One end of the first measurement switch is connected with the USB downstream port of the device under test through the first selection switch and the USB bus, and the other end of the first measurement switch is connected with the negative voltage constant current source; the negative voltage constant current source is connected with a power supply in the device under test through the USB bus; the other end of the first measurement switch is also connected with the voltage holding circuit through the second measurement switch, and the voltage holding circuit is connected with the MCU; The MCU is connected with the first measurement switch and the second measurement switch, and is used for controlling the first measurement switch to select a connection with which data line in the USB downstream port to be conducted, and is also used for controlling the second measurement switch to be conducted or disconnected; The process of the MCU controlling the IO online measurement circuit to perform online measurement is as follows: The MCU selects the current measured IO by controlling the first measurement switch, and then the MCU controls to start the second measurement switch to sample the negative voltage value of the current selected channel; The negative voltage value is input into the MCU through the voltage holding circuit; The MCU enables the internal analog-digital conversion circuit ADC to perform analog-digital conversion on the received negative voltage value to obtain the voltage value of the current measured IO under the negative voltage constant current source; The above two steps are repeatedly executed to complete the measurement of all measured IOs in the IO online measurement circuit; The MCU returns the measured voltage values of all IOs under the negative voltage constant current source to the test software, so that the test software judges whether there is an open circuit or a short circuit according to the reverse voltage value of each IO.

2. The USB downstream port performance test system of claim 1, wherein, The test software includes a product database, a test fixture database, a test history database, and a main program; The product database is used to store the characteristic parameters, measurement time, measurement duration, and judgment range value of the product to adapt to the test requirements of different products; The test fixture database is used to store the functions, capabilities, and test instruction set of the test fixture to adapt to the test of different devices under test; The test history database is used to save the product model, serial number, PID, VID, original measurement data, test time point, and determination result of the recently tested product for user traceability and export; The main program is used to import a test file and read and write the test file to the test fixture through the device under test to test the read and write rate; the main program is also used to detect the signal of the device under test to call the corresponding test parameters in the product database to complete the test of the device under test; the main program is also used to obtain the model of a product manually selected by a user and test the product according to the test parameters of the product corresponding to the model in the product database.

3. The USB sink performance test system of claim 2, wherein, The main program is also used to call a third-party hard disk speed testing tool to test the read and write rate of the USB downstream port of the device under test.

4. The USB downstream port performance test system of claim 2, wherein, The main program is used to push the test result to a comprehensive test result interface, and the comprehensive test result is displayed on the interface, which is OK or NG; When the comprehensive test result is NG, the test result and the original test data of each sub-test item are also displayed on the interface.

5. A USB downstream port performance testing method, characterized in that, The steps include: setting the USB downstream port performance test system according to any one of claims 1-4; The test software imports the USB downstream port measurement parameter setting normal range setting table into the product database; The USB downstream port measurement parameter setting normal range setting table includes model, parameter category, parameter setting, and its judgment range; The test software queries the PID, VID, and serial number of the connected USB device to determine whether there is a device under test connected; If there is a device under test connected, the test software sends the test condition to the test fixture according to the test parameters in the imported USB downstream port measurement parameter setting normal range setting table. The test fixture tests the USB downstream port performance according to the test conditions and feeds back the test results to the test software, the test software compares the received test results with the related parameters in the normal range setting table to determine whether each test item of the USB downstream port is qualified.

6. The USB downstream port performance testing method of claim 5, wherein, The test fixture tests the USB downstream port performance according to the test conditions and feeds back the test results to the test software, the test software compares the received test results with the related parameters in the normal range setting table to determine whether each test item of the USB downstream port is qualified. The test software reads and writes large file blocks to the USB high-speed hard disk connected to the USB downstream port of the device under test to determine whether the communication rate of the USB downstream port of the device under test is qualified; The test software writes the instruction of "normal load characteristic test" to the programmable electronic load inside the test fixture connected to the USB downstream port of the device under test, and reads back the voltage value of the USB interface at this time through the test fixture to determine whether the load capacity of the USB downstream port of the device under test is qualified; The test software writes the instruction of "over-current protection test" to the programmable electronic load inside the test fixture connected to the USB downstream port of the device under test, and reads back the measured parameters of the USB interface during the protection period through the test fixture, and compares them with the set parameters in the database to determine whether the output overload protection function of the USB downstream port of the device under test is qualified; The test software writes the instruction of "short-circuit protection test" to the programmable electronic load inside the test fixture connected to the USB downstream port of the device under test, and reads back the measured parameters of the USB interface during the protection period through the test fixture, and compares them with the set parameters in the database to determine whether the output short-circuit protection function of the USB downstream port of the device under test is qualified; The test software initiates the "IO open-circuit short-circuit test" test to the IO open-circuit short-circuit test circuit inside the test fixture connected to the USB downstream port of the device under test, and reads back the measured voltage readings of each IO through the test fixture, and compares them with the set parameters in the database to determine whether the IO of the USB downstream port of the device under test has open-circuit or short-circuit phenomenon.

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