System and method for testing a characteristic impedance of a signal path routing of a printed circuit board

1. Technical Field

Embodiments of the present disclosure relate to test technology, and particularly to a system and method for testing a characteristic impedance of a signal path routing of a printed circuit board (PCB).

2. Description of Related Art

Characteristic impedance testing of signal path routings of a PCB is an important phase in the manufacturing process, and is closely interrelated to product quality. For further improvements to the impedance characterization of signal routings, a prompt and accurate test of characteristic impedances of the signal path routings on the PCB is desirable.

FIG. 1 is a schematic diagram of one embodiment of a computer including a testing system for testing a characteristic impedance of a signal path routing of a printed circuit board (PCB).

FIG. 2 is a block diagram of one embodiment of the test system in the FIG. 1 .

FIG. 3 is a flowchart of one embodiment of a method for testing a characteristic impedance of a signal path routing of a PCB using the test system of FIG. 2 .

All of the processes described below may be embodied in, and fully automated via, functional code modules executed by one or more general purpose computers or processors. The code modules may be stored in any type of readable medium or other storage device. Some or all of the methods may alternatively be embodied in specialized hardware. Depending on the embodiment, the readable medium may be a hard disk drive, a compact disc, a digital video disc, or a tape drive.

FIG. 1 is a schematic diagram of one embodiment of a computer 1 including a test system 10 . In one embodiment, the computer 1 is connected to a test device 2 , where the test device 2 may be a time domain reflectometer (TDR), for example. The test device 2 selects a signal path routing of a printed circuit board (PCB) 4 via probes 5 , and tests a characteristic impedance of each of the signal path routings of the PCB 4 . The PCB 4 is positioned on a test platform 3 . Referring to FIG. 1 , the test system 10 may be used to obtain test parameters of each of the signal path routings, control the test device 2 to test the characteristic impedance of each of the signal path routings according to the test parameters, obtain test data, and analyze the test data.

The computer 1 further includes a storage 11 and a processor 12 . The storage 11 can be a hard disk drive, random access, memory, read only memory, a cache system or a combination of the aforementioned systems. The storage 11 may store various kinds of data, such as the test information. The test parameters of each of the signal path routing of the PCB 4 , and the test data, for example. The processor 12 executes one or more computerized operations of the computer 1 and other applications, to provide functions of the computer 1 .

FIG. 2 is a block diagram of one embodiment of the test system 10 in the FIG. 1 . In one embodiment, the test system 10 includes a receiving module 100 , an initializing module 101 , an obtaining module 102 , a determining module 103 , a test module 104 , an analysis module 105 , and a generation module 106 . The modules 100 , 101 , 102 , 103 , 104 , 105 , and 106 may comprise one or more computerized codes to be executed by the processor 12 to perform one or more operations of the test system 1 .

The receiving module 100 receives test information. The test information may include an Internet Protocol address of the test device 2 , a preset storage path for storing the test parameters in the storage 11 , and a preset storage path for storing the test data in the storage 11 .

The initialization module 101 initializes the test device 2 connected to the computer 1 . In one embodiment, the initialization module 101 initializes the test device 2 by restoring the test device 2 to its factory settings.

The obtaining module 102 obtains status parameters of the test device 2 . In one embodiment, the status parameters of the test device 2 includes a temperature of the test device 2 and a probe parameter that determines whether probes 5 of the test device 2 are available probes. If the probes 5 of the test device 2 can select a signal path routing of the PCB 4 , the probes 5 of the test device 2 are available probes.

The determination module 103 determines whether the obtained status parameters are valid. In one embodiment, the storage 11 stores standard temperature of the test device 2 . If the obtained temperature of the test device 2 is within range of the standard temperature of the test device 2 , and if the probes of the test device 2 are available probes, the determination module 103 determines that the obtained status parameters are valid. If the obtained temperature of the test device 2 is not within range of the standard temperature of the test device 2 , and/or the probes of the test device 2 are not available probes, the determination module 103 determines that the obtained status parameters are invalid.

If the status parameters of the test device 2 are valid, the obtaining module 102 obtains test parameters of each signal path routing of the PCB 4 according to the preset storage path that stores the test parameters in the storage 11 . The test parameters of each signal path routing includes a name, a type, a length, and a standard characteristic impedance of the signal path routing.

The testing module 104 controls the test device 2 to test the characteristic impedance of a signal path routing of the PCB 4 according to the test parameters, obtain test data of the signal path routing from the test device 2 , and store the test data of the signal path routing in the storage 11 .

The analysis module 105 compares the test data of the signal path routing of the PCB 4 with a corresponding standard characteristic impedance of the signal path routing in the test parameters, and determines if the test data of the signal path routing is acceptable. If the test data of the signal path routing is within the standard characteristic impedance of the signal path routing, the test data of the signal path routing is acceptable. If the test data of the signal path routing is not within the standard characteristic impedance of the signal path routing, the test data of the signal path routing is not acceptable.

The determination module 103 determines whether any other signal path routings of the PCB 4 need to be tested.

The generation module 106 generates a test report to store the test data and the comparison results if there are no signal path routing of the PCB 4 needs to be tested, and stores the test report in the storage 11 according to the test information.

FIG. 3 is a flowchart of one embodiment of a method for testing a characteristic impedance of a signal path routing of a PCB. Depending on the embodiment, additional blocks may be added, others removed, and the ordering of the blocks may be changed.

In block S 10 , the receiving module 100 receives test information by the computer 1 .

In block S 12 , the initialization module 101 initializes the test device 2 connected to the computer 1 .

In block S 14 , the obtaining module 102 obtains status parameters of the test device 2 . The status parameters of the test device 2 includes the temperature of the test device 2 and a probe parameter that determines whether the probes 5 of the test device 2 are available probes.

In block S 16 , the determination module 103 determines whether the obtained status parameters are valid. The storage 11 stores standard temperature of the test device 2 . If the obtained temperature of the test device 2 is within range of the standard temperature of the test device 2 , and the probes of the test device 2 are available probes, the determination module 103 determines that the obtained status parameters are valid. If the obtained temperature of the test device 2 is not within range of the standard temperature of the test device 2 , and/or the probes of the test device 2 are not available probes, the determination module 103 determines that the obtained status parameters are invalid.

In block S 18 , if the status parameters of the test device are valid, the obtaining module 102 obtains test parameters of signal path routings of the PCB 4 according to the preset storage path that stores the test parameters in the storage 11 . The test parameters of each signal path routing comprises a name, a type, a length, and a standard characteristic impedance of the signal path routing. Otherwise, if the status parameters of the test device are invalid, the procedure returns to block S 12 described above.

In block S 20 , the testing module 104 controls the test device 2 to test the characteristic impedance of a signal path routing of the PCB 4 according to the test parameters.

In block S 22 , the testing module 104 obtains test data of the signal path routing from the test device 2 , and stores the test data of the signal path routing in the storage 11 .

In block S 24 , the analyzing module 105 compares the test data of the signal path routing of the PCB 4 with a corresponding standard characteristic impedance of the signal path routing in the test parameters, and determines if the test data of the signal path routing is acceptable. If the test data of the signal path routing is within the standard characteristic impedance of the signal path routing, the test data of the signal path routing is acceptable. If the test data of the signal path routing is not within the standard characteristic impedance of the signal path routing, the test data of the signal path routing is not acceptable.

In block S 26 , the determination module 103 determines whether any other signal path routings of the PCB 4 need to be tested.

In block S 28 , if there are no signal path routings of the PCB 4 that need to be tested, the generation module 106 generates a test report and the comparison results and stores the test report in the storage 11 according to the test information. Otherwise, if there are signal path routings of the PCB 4 that need to be tested, the procedure returns to block S 20 described above.

It should be emphasized that the above-described embodiments of the present disclosure, particularly, any embodiments, are merely possible examples of implementations, merely set forth for a clear understanding of the principles of the disclosure. Many variations and modifications may be made to the above-described embodiment(s) of the disclosure without departing substantially from the spirit and principles of the disclosure. All such modifications and variations are intended to be included herein within the scope of this disclosure and the present disclosure and protected by the following claims.