KR20130042225A - Test apparatus and test method - Google Patents

Abstract

PURPOSE: A device for testing a device and a testing method thereof are provided to process signals including the generation of test signals and optical signal conversion to prevent testing costs from increasing due to the decline of a processing rate caused by using additional measuring devices when testing a device comprising an optical interface. CONSTITUTION: A device(100) for testing a device comprising an optical interface comprises a test signal generating part(112) generating a test signal testing a target device(10). The device comprises an electrophotic conversion part(120) converting the test signal into an optical test signal. The device comprises an optical interface part(152) for transmitting the optical test signal converted by the electrophotic conversion part to the light input part of the target device while collecting and outputting an optical responding signal outputted by the target device. The device comprises a photoelectric transformation part(160) converting the optical responding signal outputted by the optical interface part into the responding signal of an electrical signal for transmitting. The device comprises a signal receiving part(114) receiving the responding signals transmitted by the photoelectric transformation part. [Reference numerals] (10) Target device; (110) Test part; (112) Test signal generating part; (114) Signal receiving part; (116) Expected value comparing part; (120) Electrophotic conversion part; (130) Optical signal generating part; (135) Wavelength setting part; (160) Photoelectric transformation part; (170) Optical monitor part;

Description

TEST APPARATUS AND TEST METHOD}

The present invention relates to a test apparatus and a test method.

Conventionally, the test apparatus tested devices under test, such as a CPU and a memory. In addition, a loopback test for testing at an actual operating speed has been proposed (see Patent Document 1, for example). In addition, it has been proposed to include an optical interface in the device under test (see Patent Document 2, for example).

Japanese Patent Laid-Open No. 2006-220660 International Publication No. 2007-013128

Ian A. Young, et al., "Optical I / O Technology for Tera-Scale Computing", IEEE Journal of Solid-State Circuits, January 2010, Vol. 45, No. 1, pp.235-248 Hiren D. Thacker, James D. Meindl, "Prospects for Wafer-Level Testing of Gigascale Chips with Electrical and Optical I / O Interconnects", IEEE International Test Conference, 2006, 25-1

To test a device under test with such an optical interface, the optical response signal must be detected using the optical signal as a test signal. Therefore, although it was necessary to provide the optical measuring device etc. for optical communication, in this case, a processing rate will fall and it will raise test cost.

MEANS TO SOLVE THE PROBLEM In order to solve the said subject, in the 1st aspect of this invention, the test apparatus which tests a device under test WHEREIN: The test signal generation part which produces the test signal which tests a device under test, and a test signal are used as an optical test signal. An optical interface unit for transmitting an optical conversion signal to be converted, an optical test signal converted by the optical conversion unit to an optical input unit of the device under test, and receiving and outputting an optical response signal output from the device under test; It provides a test apparatus and a test method comprising a photoelectric conversion unit for converting the optical response signal to a response signal of the electrical signal and transmitting, and a signal receiving unit for receiving the response signal transmitted by the photoelectric conversion unit.

In addition, the summary of the said invention does not enumerate all of the required features of this invention. In addition, subcombinations of these groups of features may also be invented.

FIG. 1: shows the structural example of the test apparatus 100 which concerns on this embodiment with the device under test 10. FIG.
2 shows an operation flow of the test apparatus 100 according to the present embodiment.
3 shows a modification of the operation flow of the test apparatus 100 according to the present embodiment.
FIG. 4: shows the 1st modified example of the test apparatus 100 which concerns on this embodiment with the device under test 10. FIG.
5 shows an operation flow of a first modification example of the test apparatus 100 according to the present embodiment.
FIG. 6 shows a second modification of the test apparatus 100 according to the present embodiment together with the device under test 10.

EMBODIMENT OF THE INVENTION Hereinafter, although this invention is demonstrated through embodiment of invention, the following embodiment does not limit invention according to a claim. Moreover, not all of the combination of the characteristics demonstrated in embodiment is essential to the solution means of this invention.

FIG. 1: shows the structural example of the test apparatus 100 which concerns on this embodiment with the device under test 10. As shown in FIG. The test apparatus 100 is an analog circuit, a digital circuit, a memory, a system on a chip (SOC), or the like, and tests the device under test 10 having the optical interface. The device under test 10 may be a circuit in which at least one of an analog circuit, a digital circuit, a memory, and a system on a chip (SOC) is combined with an optical interface. The device under test 10 includes one or more light input units 12 and one or more light output units 14 that transmit and receive optical signals, respectively. In addition, the device under test 10 may be provided with one or more input terminals 16 and one or more output terminals 18 for transmitting and receiving electrical signals. The input terminal 16 and the output terminal 18 may be solder bumps, lands, connectors or the like.

The test apparatus 100 supplies an optical test signal obtained by totally converting an electric test signal to the optical input unit 12 of the device under test 10. In addition, the test apparatus 100 receives an optical response signal output from the light output unit 14 of the device under test 10, receives a response signal of photoelectric conversion electricity, and compares it with an expected value. Determine whether the device 10 is good or bad. In addition, the test apparatus 100 supplies a test signal to the input terminal 16 of the device under test 10, receives a response signal output from the output terminal 18 of the device under test 10, You may judge the quality of the device under test 10 by comparing with an expected value. The test apparatus 100 includes a test unit 110, an all-optical conversion unit 120, an optical signal generator 130, a wavelength setting unit 135, a first optical switch unit 140, and a device. The interface unit 150, the photoelectric conversion unit 160, the optical monitor unit 170, and the second optical switch unit 180 are provided.

The test unit 110 outputs a test signal and receives a response signal corresponding to the test signal and compares it with the expected value. As an example, the test unit 110 acquires a test program used for testing from an external computer such as a workstation, a storage device, or the like, or acquires a test program by input from a user and executes the program. Output the test signal. In addition, the test unit 110 may display the test result as the comparison result to the user or transmit and record the result to an external computer or a storage device. The test unit 110 includes a test signal generator 112, a signal receiver 114, and an expected value comparison unit 116.

The test signal generator 112 generates a test signal for testing the device under test 10. The test signal generation unit 112 generates a test signal based on test pattern data, test sequence, etc. designated by the test program as an example. The test signal generator 112 generates a test signal used for testing the optical signal. Here, the test signal generator 112 may generate a test signal used for testing the electrical signal of the device under test 10. As an example, the test signal generator 112 generates an expected value of the response signal output from the device under test 10 in accordance with the test signal and transmits it to the expected value comparison unit 116.

The signal receiver 114 receives an electric signal converted from the optical response signal output by the device under test. Here, the signal receiving unit 114 may receive a response signal output from the device under test in accordance with the test through the device interface unit 150. The signal receiving unit 114 transmits the received signal to the expected value comparing unit 116.

The expected value comparator 116 compares the received signal received by the signal receiver 114 with the expected value. The expected value comparison unit 116 receives the expected value from the test signal generator 112. The test apparatus 100 may determine the quality of the device under test 10 based on the comparison result of the expected value comparison unit 116.

The all-optical conversion part 120 converts a test signal into an optical test signal. The all-optical conversion part 120 converts into an optical test signal by driving an LED, a laser, etc. according to a test signal as an example. Instead, the all-optical converting unit 120 may convert the light emission of the LED, laser, and the like into a test signal by modulating the light emission. In addition, the all-optical converter 120 may transmit the converted optical test signal over an optical transmission path such as an optical fiber or an optical waveguide.

The optical signal generator 130 generates an optical signal and transmits the optical signal to the device under test 10 via a path different from that of the all-optical converter 120. The optical signal generator 130 outputs, for example, an LED or a laser as continuous light (CW light) having a constant intensity. The optical signal generator 130 may be a variable wavelength light source that varies the wavelength of light to be output. The wavelength of the light output by the wavelength setting part 135 of the optical signal generation part 130 is controlled. The wavelength setting part 135 sets the wavelength of the light which a variable wavelength light source outputs according to the wavelength of the optical signal which the device under test 10 receives.

The first optical switch unit 140 receives the optical signals output from the optical signal generating unit 130 and the all-optical converting unit 120, and selects one of the optical signals to input to the optical interface unit 152. . As an example, the first optical switch unit 140 may be a waveguide switch that switches a transmission path by combining a waveguide structure with a change in refractive index caused by an external input such as heat, light, or electricity. The first optical switch unit 140 is a two-wavelength optical waveguide, and after changing the phase of an optical signal passing through an electric field or the like to one optical path, the first optical switch unit 140 combines with the other optical waveguide. It may be a switch.

Alternatively, the first optical switch unit 140 may drive the optical fiber with an electromagnetic actuator or the like and switch from the optical fiber being transmitted to another optical fiber to be transmitted. Alternatively, the first optical switch unit 140 may switch the light beam enlarged by the lens or the like into an optical transmission path that needs to be transmitted by operating a prism or a mirror. Alternatively, the first optical switch unit 140 may switch the optical transmission path by inserting a micron size mirror or shutter using MEMS (Micro Electro Mechanical Systems) technology for the light beam propagating through the space.

The device interface unit 150 mounts the device under test 10. The device interface unit 150 sucks and fixes the device under test 10 as an example. The device interface unit 150 has an optical interface unit 152. In addition, the device interface unit 150 may further include an electrical interface unit 156 when the electrical signal is exchanged with the device under test 10 to execute the test.

The optical interface unit 152 transmits the optical test signal converted by the all-optical conversion unit 120 to the optical input unit of the device under test 10, and receives the optical response signal output by the device under test 10. Output The optical interface unit 152 may transmit the optical signal generated by the optical signal generation unit 130 to the optical input unit of the device under test 10 by switching of the first optical switch unit 140. As an example, the optical interface unit 152 receives an optical signal from the first optical switch unit 140 using an optical transmission path, and outputs an optical signal to the optical monitor unit 170 using the optical transmission path. The optical interface unit 152 includes, for example, a light output unit 154 or more of the light input unit 12 included in the device under test 10, and an optical output unit included in the device under test 10 ( 14 or more light inputs 155.

The light output unit 154 outputs an optical signal to the device under test 10. The light output unit 154 outputs an optical signal as a light beam propagating through a space, for example, by a lens, a prism, a mirror, or the like. Alternatively, the light output unit 154 may arrange the output end of the light transmission path in the vicinity of the light input unit 12 of the device under test 10 or in contact with the light input unit 12 to pass an optical signal. do. The light output unit 154 may include a collimating lens at the output end of the light transmission path.

The optical input unit 155 receives the optical response signal from the device under test 10. The optical input unit 155, like the optical output unit 154, may receive an optical signal by a lens, a prism, and / or a mirror, or the like, and instead the device 10 under test receives an input terminal of the optical transmission path. May be disposed in the vicinity of the light output unit 14 or in a position in contact with the light output unit 14 to receive an optical response signal.

The electrical interface unit 156 is electrically connected to the device under test 10 to transmit and receive electrical signals. The electrical interface unit 156 receives the test signal from the test signal generator 112 and supplies the test signal to the device under test 10, and responds to the response signal output from the test device 10 according to the test signal. It transmits to the signal receiving part 114. In addition, the electrical interface unit 156 may supply the device under test 10 with a clock signal and / or a power supply having a lower frequency than the optical test signal. The electrical interface unit 156 includes, for example, an output terminal 158 of the number or more of the input terminals 16 included in the device under test 10, and an output terminal 18 provided by the device under test 10. More than a number of input terminals 159.

The output terminal 158 may be a terminal, a probe, a cantilever, a membrane bump, or the like in direct contact with the input terminal 16. In addition, when the input terminal 16 is a connector, the output terminal 158 may be a connector fitting with the input terminal 16. Like the output terminal 158, the input terminal 159 may be a terminal, a probe, a cantilever, a membrane bump, a connector, or the like that directly contacts the output terminal 18.

The photoelectric conversion unit 160 converts the optical response signal output from the optical interface unit 152 into a response signal of an electrical signal and transmits the response signal to the signal reception unit 114. As an example, the photoelectric conversion unit 160 converts an optical response signal into a response signal by using a photodiode. Instead, the photoelectric conversion unit 160 may be an image sensor such as a CCD. In this case, the photoelectric conversion unit 160 receives a plurality of optical response signals by a plurality of optical transmission paths, and thus a plurality of response signals. You may convert to.

The optical monitor 170 converts an input optical signal into an electrical signal and monitors it. As an example, the optical monitor 170 converts an optical signal into an electrical signal by using a photodiode. Alternatively, the optical monitor unit 170 may be an image sensor such as a CCD. In this case, the optical monitor unit 170 receives a plurality of optical signals by a plurality of optical transmission paths, and converts them into a plurality of electrical signals. You may convert.

The second optical switch unit 180 selects and inputs an optical response signal output from the optical interface unit 152 to either one of the optical monitor unit 170 and the photoelectric conversion unit 160. Like the first optical switch unit 140, the second optical switch unit 180 may be an optical switch of a waveguide type, a mechanical type, or a MEMS type.

2 shows an operation flow of the test apparatus 100 according to the present embodiment. The test apparatus 100 mounts the device under test 10 on the device interface unit 150 (S200). The test apparatus 100 mounts the device under test 10 in a package, wafer, or chip shape, for example. As an example, the test apparatus 100 temporarily fixes the device under test 10 to an XYZθ stage or the like moving in at least three directions and a rotational direction, and adjusts the device under test 10 by adjusting the position of the XYZθ stage. It mounts in the part 150.

Next, the test apparatus 100 confirms the connection state of the device under test 10 and the device interface unit 150 (S210). The test apparatus 100 confirms the connection state between the optical input unit 12 and the optical output unit 14 and the optical interface unit 152 of the device under test 10. In this case, the first optical switch unit 140 selects the optical signal output from the optical signal generator 130 and inputs the optical signal to the optical interface unit 152, and the second optical switch unit 180 provides the optical interface. The optical response signal output from the unit 152 is selected and input to the optical monitor unit 170. And the test apparatus 100 detects the connection state of the device under test 10 and the optical interface unit 152 according to the monitoring result of the optical monitor unit 170, and as the connection state is detected, it is tested. The test of the device 10 is started.

In order to detect the connection state between the device under test 10 and the optical interface unit 152, the optical signal generation unit 130 may generate CW light having a predetermined intensity and supply it to the device under test 10. . And the optical monitor part 170 detects the connection state of the device under test 10 and the optical interface part 152, when monitoring the CW light of a predetermined intensity range.

When the device under test 10 includes the plurality of light input units 12 and the light output units 14, the test apparatus 100 includes a plurality of optical signals generated by one optical signal generator 130. The optical switch for switching to the transmission path is provided in the first optical switch unit 140, and the optical interface unit 152 may input the optical signals transmitted by the plurality of optical transmission paths to the plurality of optical input units 12, respectively. . Instead, the test apparatus 100 transmits the optical signals generated by the plurality of optical signal generators 130 to the plurality of optical transmission paths, respectively, and the optical interface unit 152 transmits the plurality of optical transmission paths. The optical signals to be input may be input to the plurality of optical input units 12, respectively.

The optical interface unit 152 receives the optical response signals output from the plurality of optical output units 14 into the plurality of optical transmission paths, and passes them to the second optical switch unit 180. The second optical switch unit 180 synchronizes the plurality of optical response signals with one optical monitor unit 170 so as to sequentially monitor the plurality of optical response signals with the switching timing of the first optical switch unit 140. The transmission path and the optical monitor 170 are selected and switched. Thereby, the pair of optical signal generation unit 130 and the optical monitor unit 170 can detect the connection between the plurality of optical input unit 12, the optical output unit 14, and the optical interface unit 152.

Instead, the test apparatus 100 is provided with a plurality of optical monitors 170, so that the second optical switch unit 180 with less or fewer switching times, the light input unit 12 and the light output unit. The connection between the 14 and the optical interface unit 152 may be detected. Instead, the test apparatus 100 includes a plurality of optical monitors 170 and a plurality of optical signal generators 130 to provide a first optical switch 140 and a second optical switch 180. With fewer switching times or without switching, the connection of the plurality of light input units 12 and the light output units 14 and the optical interface unit 152 may be detected.

In addition, the test apparatus 100 may branch and input the optical signal which the 1 or more optical signal generation part 130 generate | occur | produced into the some optical transmission path. In this case, the test apparatus 100 may monitor each of the plurality of optical response signals output by the optical interface unit 152 with the same number of optical monitor units 170 as the number of optical response signals. Thereby, the test apparatus 100 can detect the connection of the some optical input part 12, the optical output part 14, and the optical interface part 152 simultaneously. When the connection state between the device under test 10 and the optical interface unit 152 cannot be detected, the test apparatus 100 returns to step S200 and mounts the device under test 10 again.

Here, when the connection state cannot be detected even if the device under test 10 is repeatedly mounted, the test apparatus 100 may determine that the device under test 10 is defective. For example, when the test apparatus 100 cannot detect the connected state even after repeating the mounting of the device under test 10 a predetermined number of times, the light input unit 12 of the device under test 10 and / Or it determines with the light output part 14 defective.

In addition, the test apparatus 100 may detect the passage characteristic of the optical component provided in the device under test 10. The device under test 10 includes optical components such as a WDM combiner and an optical filter, for example, in the case where the device under test 10 is divided or combined according to the wavelength of the light input from the light input unit 12. . The test apparatus 100 changes the wavelength of the optical signal generated by the optical signal generator 130 by the wavelength setting unit 135, supplies the optical signal to the optical input unit 12, and simultaneously outputs the light from the optical output unit 14. The optical response signal is received, and the optical response unit 170 monitors the optical response signal. As a result, the test apparatus 100 can monitor the wavelength dependence of the input optical signal with respect to the optical response signal of the device under test 10, and thus the pass characteristic of the optical component provided in the device under test 10 can be monitored. Can be detected.

When the test apparatus 100 detects a connection state between the device under test 10 and the optical interface unit 152, the test apparatus 100 detects a connection state of an electrical signal between the device under test 10 and the electrical interface unit 156. . The test apparatus 100 inputs a predetermined electrical signal from the test signal generator 112, that is, an electrical signal having a logic value or pattern, such as a predetermined Hi / Lo, through the output terminal 158. Supplies). And the test apparatus 100 receives the response signal output from the output terminal 18 to the signal receiving part 114 via the input terminal 159, and detects the connection state of an electrical signal.

For example, the test apparatus 100 supplies a constant voltage as a predetermined electrical signal from the test signal generator 112, and the signal receiver 114 receives a voltage value within a predetermined range to establish a connection state. Detect. The test apparatus 100 determines that the device under test 10 and the device interface unit 150 can be normally connected based on detecting the connection state between the device under test 10 and the electrical interface unit 156. You may also If the test apparatus 100 cannot detect the connection state between the device under test 10 and the electrical interface unit 156, the test apparatus 100 returns to step S200 to mount the device under test 10 again.

Here, when the connection state cannot be detected even if the device under test 10 is repeatedly mounted, the test apparatus 100 may determine that the device under test 10 is defective. For example, when the test apparatus 100 cannot detect the connection state even if the mounting of the device under test 10 is repeated a predetermined number of times, the input terminal 16 of the device under test 10 and / or It is determined that the output terminal 18 is defective.

The test apparatus 100 starts a test of the device under test 10 when detecting the normal connection between the device under test 10 and the device interface unit 150. The test apparatus 100 determines whether the test to be performed is an optical test or an electrical signal test (S220). The test apparatus 100 determines, for example, whether or not a test to be executed from a test program, a test sequence, a control command, or the like is an optical test.

When the test to be performed is a test of an electrical signal, the test apparatus 100 supplies a test signal generated from the test signal generator 112 to the input terminal 16 through the output terminal 158 (S230). . Here, the test signal generator 112 transmits the expected value corresponding to the supplied test signal to the expected value comparison unit 116. The test apparatus 100 receives the response signal that the device under test 10 outputs from the output terminal 18 in accordance with the supplied test signal to the signal receiving unit 114 via the input terminal 159 (S240). . The signal receiving unit 114 transmits the received response signal to the expected value comparing unit 116, and the expected value comparing unit 116 receives the response signal received from the signal receiving unit 114 and the test signal generating unit 112. The expected value is compared to determine whether the device under test 10 is successful (S250).

When the test to be performed is an optical test, the test apparatus 100 uses the first optical switch unit 140 to connect the all-optical conversion unit 120 and the optical interface unit 152 to the second optical switch unit 180. The optical interface unit 152 and the photoelectric conversion unit 160 are connected respectively. The test apparatus 100 converts the test signal generated from the test signal generator 112 into an optical test signal through the all-optical converter 120 and supplies it to the optical input unit 12 (S260). Here, the test signal generator 112 transmits the expected value corresponding to the supplied test signal to the expected value comparison unit 116.

The test apparatus 100 converts the optical response signal that the device under test 10 outputs from the optical output unit 14 according to the supplied optical test signal into a response signal which is an electrical signal through the photoelectric conversion unit 160. The signal is received by the signal receiver 114 (S270). The signal receiving unit 114 transmits the received response signal to the expected value comparing unit 116, and the expected value comparing unit 116 receives the response signal received from the signal receiving unit 114 and the test signal generating unit 112. The expected value is compared to determine whether the device under test 10 is successful (S250).

The test apparatus 100 repeats step S220 to step S250 until the test to be performed is completed (S280). Thereby, the test apparatus 100 can perform the optical test by the optical test signal of the device under test 10. In addition, the test apparatus 100 can perform a test in which the optical test by the optical test signal of the device under test 10 and the test by the electric signal are mixed. In addition, since the test apparatus 100 can independently perform the transfer of the optical signal and the transfer of the electrical signal, the response signal to the optical test signal can be independently received when both the electrical signal and the optical signal are output. Can be. Similarly, even when both the electrical signal and the optical signal are output, the test apparatus 100 can independently receive the response signal to the electrical test signal. In addition, when the device under test 10 is supplied with an electric signal from a device other than the test device 100 or when the supply of the electric signal is not required, the test device 100 is connected to the device under test 10. The optical test may be performed only by connecting the optical interface unit 152.

In addition, the test apparatus 100 transmits a high speed test signal and / or a response signal as an optical signal, and transmits a low speed clock signal, a test signal, a response signal, and / or a power supply as an electric signal to perform the test. Testing of the device 10 can be performed. This makes it possible to transmit and receive a test signal and a response signal with the device under test 10 at high speed by transmitting, as an optical signal, a high frequency signal of several hundred MHz or more, which is difficult to transmit with an electric signal. In addition, the test apparatus 100 may perform the test by operating the device under test 10 at the actual operating speed, for example.

In addition, the test apparatus 100 includes at least two optical switch units, an optical signal generator 130, and an optical monitor unit 170. The device under test 10 and the optical interface unit 152 are provided. The connected state of can be detected. Thus, since the test apparatus 100 can speed test operation and can detect the connection state with the device under test 10, the test throughput can be increased.

3 shows a modification of the operation flow of the test apparatus 100 according to the present embodiment. In this modification, the same code | symbol is attached | subjected to what is substantially the same as the operation flow of the test apparatus 100 which concerns on this embodiment shown in FIG. 2, and description is abbreviate | omitted. This modification performs the test corresponding to the case where the device under test 10 outputs an electrical signal in accordance with an input optical signal, or outputs an optical response signal in accordance with an input electrical signal.

When the test apparatus 100 detects normal connection between the device under test 10 and the device interface unit 150 in step 210, the test apparatus 100 starts testing the device under test 10. The test apparatus 100 determines whether to use the test signal of the electrical signal or the optical test signal (S220). When using the test signal of the electrical signal, the test apparatus 100 supplies the test signal generated from the test signal generator 112 to the input terminal 16 through the output terminal 158 (S230). Here, the test signal generator 112 transmits the expected value corresponding to the supplied test signal to the expected value comparison unit 116.

Next, the test apparatus 100 determines whether the device under test 10 outputs a response signal or an optical response signal according to the test signal (S310). The test apparatus 100 determines whether to output a response signal or an optical response signal according to the test signal, for example, from a test program, a test sequence, a control command, or the like. Instead, the test apparatus 100 may determine in advance whether to output a response signal or an optical response signal in accordance with the test signal.

When the device under test 10 outputs a response signal which is an electrical signal, the test apparatus 100 outputs the response signal output from the output terminal 18 through the input terminal 159 as in the example of FIG. 2. Received by the signal receiving unit 114 (S240). The signal receiving unit 114 transmits the received response signal to the expected value comparing unit 116, and the expected value comparing unit 116 receives the response signal received from the signal receiving unit 114 and the test signal generating unit 112. The expected value is compared to determine whether the device under test 10 is successful (S250).

On the other hand, when the device under test 10 outputs the optical response signal, the test apparatus 100 responds to the optical response signal output from the optical output unit 14 as an electrical signal through the photoelectric conversion unit 160. The signal is converted into a signal and received by the signal receiver 114 (S270). The signal receiving unit 114 transmits the received response signal to the expected value comparing unit 116, and the expected value comparing unit 116 receives the response signal received from the signal receiving unit 114 and the test signal generating unit 112. The expected value is compared to determine whether the device under test 10 is successful (S250).

When the optical test signal is used, the test apparatus 100 converts the test signal generated from the test signal generator 112 into an optical test signal through the all-optical converter 120 and supplies the optical test signal to the optical input unit 12. (S260). Here, the test signal generator 112 transmits the expected value corresponding to the supplied test signal to the expected value comparison unit 116.

Next, the test apparatus 100 determines whether the device under test 10 outputs a response signal or an optical response signal according to the optical test signal (S320). The test apparatus 100 determines whether to output a response signal or an optical response signal according to the optical test signal, for example, from a test program, a test sequence, a control command, or the like. Instead, the test apparatus 100 may determine in advance whether to output a response signal or an optical response signal in accordance with the optical test signal.

When the device under test 10 outputs the optical response signal, the test apparatus 100 uses the photoelectric conversion unit 160 to output the optical response signal output from the optical output unit 14 as in the example of FIG. 2. The signal is converted into a response signal which is an electrical signal through the signal receiving unit 114 (S270). The signal receiving unit 114 transmits the received response signal to the expected value comparing unit 116, and the expected value comparing unit 116 receives the response signal received from the signal receiving unit 114 and the test signal generating unit 112. The expected value is compared to determine whether the device under test 10 is successful (S250).

On the other hand, when the device under test 10 outputs a response signal which is an electrical signal, the test apparatus 100 outputs the response signal output from the output terminal 18 via the input terminal 159 to the signal receiver 114. Received to (S240). The signal receiving unit 114 transmits the received response signal to the expected value comparing unit 116, and the expected value comparing unit 116 receives the response signal received from the signal receiving unit 114 and the test signal generating unit 112. The expected value is compared to determine whether the device under test 10 is successful (S250).

According to the test apparatus 100 according to the present modification example, the device 10 under test corresponds to a case in which an electric signal is output in accordance with an optical signal input or an optical response signal is output in accordance with an input electrical signal. You can run the test. In addition, the device under test 10 having the light input unit 12 and without the light output unit 14, or the device under test 10 having the light output unit 14 and without the light input unit 12. Test can be performed.

FIG. 4: shows the 1st modified example of the test apparatus 100 which concerns on this embodiment with the device under test 10. FIG. In this modification, the same code | symbol is attached | subjected to what is substantially the same as the test apparatus 100 which concerns on this embodiment shown in FIG. 1, and description is abbreviate | omitted. The test apparatus 100 of the present modification performs the optical loopback test of the device under test 10. The test apparatus 100 of the present modification includes a loopback optical path portion 410.

The loopback optical path unit 410 loops back the optical response signal from the device under test 10 to the device under test 10. As an example, the loopback optical path unit 410 connects the optical output unit 14 and the optical input unit 12 of the device under test 10 with an optical transmission path such as an optical fiber or an optical waveguide. The loopback optical path unit 410 has a device according to the item to be tested.

The loopback optical path part 410 has a phase control part which controls the phase timing of the optical signal which passes as an example. The phase control unit may be an optical phase modulator that changes the refractive index by applying an electric field to an electro-optic crystal such as a ferroelectric crystal and controls the phase of light to be transmitted. Alternatively, the phase control unit may be an optical phase modulator that controls the phase of light transmitted by applying an electric field to the Mahgender waveguide. Alternatively, the phase control unit may be an optical phase modulator for controlling the phase of the transmitted light by changing the fiber length by adding a physical force to the optical fiber for transmitting the optical signal.

The phase control part can control the skew of the optical signal input by looping back to the device under test 10 by changing the phase timing of the optical signal passing through. That is, the test apparatus 100 has the phase control part in the loopback optical path part 410, and can perform the skew-proof test etc. of the device under test 10. FIG. In addition, the phase control part can control the jitter of the optical signal input by looping back to the device under test 10 by changing the phase timing of the optical signal passing through. That is, the test apparatus 100 has a phase control part in the loopback optical path part 410, and can perform a jitter strength test etc. of the device under test 10. FIG.

The loopback optical path section 410 also has an attenuator section that attenuates the intensity of the optical signal passing therethrough. The attenuator portion is preferably a variable attenuator capable of controlling the amount of attenuation. The attenuator unit can control the intensity of the optical signal inputted by looping back to the device under test 10 by changing the attenuation amount of the optical signal passing therethrough. That is, the test apparatus 100 has an attenuator portion in the loopback optical path portion 410, and can perform attenuation strength test or the like of the light intensity of the device under test 10. Here, the test apparatus 100 is combined with the skew strength test of the device under test 10, and can perform the smoothing characteristic in an optical test.

The loopback optical path unit 410 may be an optical transmission path connecting the light output unit 14 and the light input unit 12 of the device under test 10. In this case, the test apparatus 100 generates a PRBS signal (Pseudorandom Binary (Bit) Sequence) by the device under test 10, and the design for test (DFT) of the device under test 10 is designed. Can test the function.

The first optical switch unit 140 receives an optical signal output from the loopback optical path unit 410 and the optical signal generator 130, selects one optical signal, and outputs the optical signal to the optical interface unit 152. . The second optical switch unit 180 selects and inputs an optical signal input from the optical interface unit 152 to either one of the loopback optical path unit 410 and the optical monitor unit 170.

5 shows the operation flow of the first modification example of the test apparatus 100 according to the present embodiment. The operation flow of this modified example attaches | subjects the same code | symbol to the thing substantially the same as the operation flow of the test apparatus 100 which concerns on this embodiment shown in FIG. 2, and abbreviate | omits description.

When the test apparatus 100 detects normal connection between the device under test 10 and the device interface unit 150 in step 210, the test apparatus 100 starts testing the device under test 10. The test apparatus 100 determines whether to perform the optical loopback test or the test of the electrical signal (S510). When the test apparatus 100 executes the test of the electrical signal, the test device 10 supplies the test signal to the device under test 10 as shown in steps S230 to S250 of FIG. The response signal outputted accordingly is received, and the quality of the device under test 10 is determined by comparing with the expected value.

When the optical loopback test is executed, the test apparatus 100 switches the first optical switch unit 140 to output the optical signal output from the loopback optical path unit 410 to the optical interface unit 152, The optical switch unit 180 is switched to input the optical response signal from the optical interface unit 152 to the loopback optical path unit 410. The test apparatus 100 supplies the test signal generated from the test signal generator 112 to the input terminal 16 via the output terminal 158 (S520).

The test signal generated by the test signal generator 112 is, for example, a test pattern used for the control command and / or the optical loopback test for starting the loopback test in the device under test 10. In addition, the test signal generator 112 transmits the expected value corresponding to the optical loopback test that has been initiated to the expected value comparison unit 116. The device under test 10 starts the optical loopback test in response to receiving the test signal from the test apparatus 100 from the input terminal 16, and outputs the test result from the output terminal 18 as a response signal.

The test apparatus 100 receives the response signal that the device under test 10 outputs from the output terminal 18 to the signal receiving unit 114 through the input terminal 159 (S530). The signal receiving unit 114 transmits the received response signal to the expected value comparing unit 116, and the expected value comparing unit 116 receives the response signal received from the signal receiving unit 114 and the test signal generating unit 112. The expected value is compared to determine whether the device under test 10 is successful (S250). The test apparatus 100 repeats step S510 to step S250 until the test to be performed is completed (S280). Thereby, the test apparatus 100 can perform the optical loopback test of the device under test 10.

In the above modification, the test apparatus 100 has described an example of transmitting and receiving a response signal of an optical loopback test of the device under test 10 by an electric signal. Instead, for example, when the device under test 10 has an optical input of a control signal and / or an optical output of an optical response signal, the test apparatus 100 starts the optical loopback test and / or the optical response. Send and receive signals as optical signals. For example, the device under test 10 further includes a pair of the optical signal generator 130 and the optical monitor 170, and the optical loopback test of the control signal of the device under test 10 is performed. The start and the like are supplied as an optical signal, and an optical response signal is received.

In this case, the optical signal generating unit 130 connected to the optical input unit of the control signal of the device under test 10 is in addition to the optical signal used for connection detection between the device under test 10 and the optical interface unit 152. Generate an optical control signal, including the initiation of an optical loopback test. In addition to the connection detection of the device under test 10 and the optical interface unit 152, the optical monitor unit 170 connected to the optical output unit of the optical response signal of the device under test 10 receives the optical response signal. Monitor. Thereby, the test apparatus 100 can perform the optical loopback test of the device under test 10 with the optical control signal.

FIG. 6: shows the 2nd modified example of the test apparatus 100 which concerns on this embodiment with the device under test 10. FIG. In this modification, the same code | symbol is attached | subjected to what is substantially the same as the 1st modification of the test apparatus 100 which concerns on this embodiment shown in FIG. 1, and the test apparatus 100 shown in FIG. The test apparatus 100 according to the present modification performs a test by an electrical signal of the device under test 10, an optical test, and an optical loopback test.

The first optical switch unit 140 receives an optical signal output from the optical signal generator 130, the loopback optical path unit 410, and the all-optical conversion unit 120, and selects one of the optical signals. Input to the optical interface unit 152. The second optical switch unit 180 selects and inputs an optical response signal from the optical interface unit 152 from one of the optical monitor unit 170, the loopback optical path unit 410, and the photoelectric conversion unit 160. Let's do it.

When detecting the connection between the device under test 10 and the optical interface unit 152, the test apparatus 100 switches the first optical switch unit 140 to output an optical signal output from the optical signal generator 130. Is input to the optical interface unit 152. In addition, the test apparatus 100 switches the second optical switch unit 180 to input the optical response signal from the optical interface unit 152 to the optical monitor unit 170. The test apparatus 100 can detect the connection of the device under test 10 and the device interface unit 150 in substantially the same operation as step S210 described in the above embodiment.

When the test apparatus 100 executes an optical test using the optical test signal, the test apparatus 100 switches the first optical switch unit 140 to output the optical test signal output from the all-optical converting unit 120 to the optical interface unit 152. Enter it. In addition, the test apparatus 100 switches the second optical switch unit 180 to input the optical response signal from the optical interface unit 152 to the photoelectric conversion unit 160. In this example, the optical test of the device under test 10 can be executed in substantially the same operation as the operation flow of the example of the test apparatus 100 according to the present embodiment shown in FIG. 2 or FIG. 3.

When the optical loopback test is executed, the test apparatus 100 switches the first optical switch unit 140 to input the optical signal output from the loopback optical path unit 410 to the optical interface unit 152. In addition, the test apparatus 100 switches the second optical switch unit 180 to input the optical response signal from the optical interface unit 152 to the loopback optical path unit 410. In this example, the optical loopback test of the device under test 10 can be executed by substantially the same operation as that of the first modification of the test apparatus 100 according to the present embodiment shown in FIG. 5.

In the above embodiment, the all-optical converter 120 converts one test signal into an optical test signal having a corresponding wavelength and transmits one optical transmission path to one optical input unit 12. An example was explained. Instead, the all-optical converting unit 120 may convert the light test signal having a plurality of wavelengths corresponding to the plurality of test signals, transmit one light transmission path, and supply the light transmission unit 12 to one light input unit 12. That is, the all-optical converter 120 converts and combines a plurality of test signals into optical test signals having corresponding wavelengths, respectively, and supplies the optical test signals having overlapping wavelengths to the device under test 10.

In addition, in the above embodiment, the photoelectric conversion unit 160 converts the optical response signal of one wavelength transmitted from one optical output unit 14 to one optical transmission path into one corresponding response signal. An example was explained. Instead, the photoelectric conversion unit 160 may convert the optical response signals of the plurality of wavelengths transmitted from one light output unit 14 to one optical transmission path into corresponding plurality of response signals. That is, the photoelectric conversion part 160 photoelectrically converts the response signal which overlapped the wavelength received from the device under test 10 into a plurality of response signals according to a plurality of test signals after splitting.

In this case, the device under test 10 that has received the optical test signal with overlapping wavelengths, for example, splits the optical test signal inside the device under test 10 and applies the optical test signal to each of a plurality of optical circuits to be tested. Distribute and supply. The device under test 10 outputs from the light output unit 14 after combining a plurality of response signals by a plurality of optical circuits to form an optical response signal having overlapping wavelengths. Thereby, a plurality of optical test signals can be supplied to the device under test 10 in one optical transmission path, and a plurality of optical response signals can be received in one transmission path. The light test can be run simultaneously.

As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It is apparent to those skilled in the art that various changes or improvements can be added to the above embodiments. It is clear from description of a claim that the form which added such a change or improvement can also be included in the technical scope of this invention.

The order of execution of each process such as operations, procedures, steps, and steps in the devices, systems, programs, and methods shown in the claims, the specification, and the drawings is specifically stated as "before", "before", and the like. It should be noted that the present invention may be realized in any order unless the output of the previous process is used in the subsequent process. The operation flow in the claims, the specification, and the drawings, even if described using "priority", "next," etc. for convenience, does not mean that it is essential to carry out in this order.

10 device under test
12 optical inputs
14 light output
16 input terminals
18 output terminals
100 test device
110 test part
112 test signal generator
114 signal receiver
116 expected value comparison
120 all-optical converter
130 optical signal generator
135 wavelength setting part
140 first optical switch unit
150 device interface
152 optical interface
154 light output
155 optical inputs
156 electrical interface
158 output terminals
159 input terminals
160 photoelectric conversion unit
170 light monitor
180 second optical switch unit
410 Loopback Light Path Section

Claims (18)

In a test apparatus for testing a device under test,
A test signal generator for generating a test signal for testing the device under test;
An all-optical converting unit converting the test signal into an optical test signal
An optical interface unit which transmits the optical test signal converted by the all-optical conversion unit to an optical input unit of the device under test, and receives and outputs an optical response signal output by the device under test;
A photoelectric conversion unit converting the optical response signal output by the optical interface unit into a response signal of an electrical signal and transmitting the response signal; And
Signal receiving unit for receiving a response signal transmitted by the photoelectric conversion unit
/ RTI >
tester.
The method of claim 1,
The test device,
An optical signal generator for generating an optical signal; And
A first optical switch unit which receives an optical signal outputted from the optical signal generator and the all-optical converter, selects one optical signal and inputs the optical signal to the optical interface unit
≪ / RTI >
tester.
The method of claim 2,
The optical signal generator includes a variable wavelength light source for varying the wavelength of the light to be output,
tester.
The method of claim 3,
The test device,
A wavelength setting unit that sets a wavelength of light output by the variable wavelength light source according to a wavelength of an optical signal received by the device under test
≪ / RTI >
tester.
The method of claim 2,
The test device,
An optical monitor configured to convert an input optical signal into an electrical signal and monitor the converted optical signal; And
A second optical switch unit for selecting and inputting an optical response signal output from the optical interface unit to either the optical monitor unit or the photoelectric conversion unit
≪ / RTI >
tester.
The method of claim 5,
The first optical switch unit selects an optical signal output by the optical signal generator and inputs the optical signal to the optical interface unit,
The second optical switch unit selects and inputs an optical response signal output from the optical interface unit to the optical monitor unit,
The test apparatus detects a connection state between the device under test and the optical interface unit according to the result monitored by the optical monitor unit, and starts a test of the device under test as the connection state is detected.
tester.
The method of claim 1,
The test apparatus further includes an electrical interface unit electrically connected to the device under test to transmit and receive an electrical signal.
The electrical interface unit receives a test signal from the test signal generator and supplies the test signal to the device under test, and receives a response signal output by the device under test according to a test signal and transmits the response signal to the signal receiver.
tester.
8. The method according to any one of claims 1 to 7,
The all-optical conversion unit converts and combines a plurality of test signals into optical test signals of corresponding wavelengths, respectively, and supplies the optical test signals having overlapping wavelengths to the device under test,
Said photoelectric conversion part photoelectrically converts the optical response signal in which the wavelength received from the said device under test overlaps, and then into a plurality of response signals according to the plurality of test signals,
tester.
In a test apparatus for testing a device under test,
An optical signal generator for generating an optical signal;
An optical monitor configured to convert an input optical signal into an electrical signal and monitor the converted optical signal;
A loopback optical path section for looping back an optical response signal from the device under test to the device under test;
A first optical switch unit which receives an optical signal output from the loopback optical path unit and the optical signal generation unit, selects and outputs one of the optical signals;
A second optical switch unit which selects and inputs an input optical signal to either the loopback optical path unit or the optical monitor unit;
An optical interface unit configured to input an optical signal output from the first optical switch unit to an optical input unit of the device under test, and input an optical response signal output from the device under test to the second optical switch unit;
/ RTI >
tester.
10. The method of claim 9,
The test device,
A test signal generator for generating a test signal for testing the device under test;
A signal receiver which receives a response signal output by the device under test according to a test signal; And
An electrical interface unit electrically connected to the device under test to transmit and receive an electrical signal
Further comprising:
The electrical interface unit receives a test signal from the test signal generator and supplies the test signal to the device under test, and receives a response signal output by the device under test according to a test signal and transmits the response signal to the signal receiver.
tester.
10. The method of claim 9,
The test device,
A test signal generator for generating a test signal for testing the device under test;
A signal receiver which receives a response signal output by the device under test according to a test signal;
An all-optical converter converting the test signal into an optical test signal; And
A photoelectric conversion unit converting an input optical signal into an electrical signal and transmitting the converted optical signal to the signal receiving unit
Further comprising:
The first optical switch unit receives an optical signal output from the optical signal generator, the loopback optical path unit, and the all-optical conversion unit, selects one optical signal and inputs the optical signal to the optical interface unit,
Wherein the second optical switch unit selects and inputs an optical response signal from the optical interface unit from one of the optical monitor unit, the loopback optical path unit, and the photoelectric conversion unit,
tester.
The method of claim 11,
The test apparatus further includes an electrical interface unit electrically connected to the device under test to transmit and receive an electrical signal.
The electrical interface unit receives a test signal from the test signal generator and supplies the test signal to the device under test, and receives a response signal output by the device under test according to a test signal and transmits the response signal to the signal receiver.
tester.
10. The method of claim 9,
The loopback optical path unit includes a phase control unit controlling phase timing of an optical signal passing through the loopback optical path unit.
tester.
10. The method of claim 9,
The optical signal generator includes a variable wavelength light source capable of varying the wavelength of the light to be output,
tester.
15. The method of claim 14,
The test apparatus further includes a wavelength setting unit for setting a wavelength of light output by the variable wavelength light source according to a wavelength of an optical signal received by the device under test,
tester.
16. The method according to any one of claims 9 to 15,
The first optical switch unit selects an optical signal output by the optical signal generator and inputs the optical signal to the optical interface unit,
The second optical switch unit selects and inputs an optical response signal output from the optical interface unit to the optical monitor unit,
The test apparatus detects a connection state between the device under test and the optical interface unit according to the result monitored by the optical monitor unit, and starts the test of the device under test as the connection state is detected.
tester.
In a test method for testing a device under test,
A test signal generation step of generating a test signal for testing the device under test;
An all-optical conversion step of converting the test signal into an optical test signal;
An optical interface step of inputting an optical test signal converted in the all-optical conversion step into an optical input unit of the device under test, receiving and outputting an optical response signal output from the device under test;
A photoelectric conversion step of converting and transmitting the optical response signal output in the optical interface step into a response signal of an electrical signal; And
A signal receiving step of receiving a response signal transmitted in the photoelectric conversion step
/ RTI >
Test Methods.
In a test method for testing a device under test,
An optical signal generating step of generating an optical signal;
An optical monitor step of converting an input optical signal into an electrical signal to an optical monitor;
A loopback step of transmitting an optical response signal from the device under test to a loopback optical path section to the device under test;
A second optical switch step of selecting and inputting an input optical signal to one of the loopback optical path unit and the optical monitor unit;
A first optical switch step of receiving an optical signal generated in the loopback optical path unit and the optical signal generating step and selecting and outputting one of the optical signals by a first optical switch unit;
An optical interface step of inputting an optical signal selected and output in the first optical switch step to an optical input of the device under test and inputting an optical response signal output from the device under test to the second optical switch;
Containing
Test Methods.

Images