CN110677193A - Industrial-grade PAM4200G error code testing device - Google Patents
Industrial-grade PAM4200G error code testing device Download PDFInfo
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- CN110677193A CN110677193A CN201910837523.4A CN201910837523A CN110677193A CN 110677193 A CN110677193 A CN 110677193A CN 201910837523 A CN201910837523 A CN 201910837523A CN 110677193 A CN110677193 A CN 110677193A
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/07—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems
- H04B10/075—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems using an in-service signal
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P90/00—Enabling technologies with a potential contribution to greenhouse gas [GHG] emissions mitigation
- Y02P90/02—Total factory control, e.g. smart factories, flexible manufacturing systems [FMS] or integrated manufacturing systems [IMS]
Abstract
The invention provides an industrial PAM4200G error code testing device, which belongs to the field of optical module testing and comprises an MCU, a communication module, a digital signal processor, a temperature control module for controlling the temperature of the digital signal processor, a clock generator, a power supply module and an installation module for installing a module to be tested, wherein the installation module is provided with pins for enabling the module to be tested to be communicated with the MCU and the digital signal processor respectively, the output end of the MCU is connected with the input end of the temperature control module, the MCU is also connected with the clock generator, the digital signal processor and the power supply module respectively, the digital signal processor is provided with at least one group of communication channels connected with the module to be tested, and is also provided with a code type generator for testing the error code rate and an error code detector connected with the code type generator.
Description
Technical Field
The invention relates to an optical module test structure, in particular to an industrial-grade PAM4200G error code test device.
Background
Since IEEE passed through IEEE 802.3ae which is an Ethernet standard with a rate of 10Gb/s in 2002, Ethernet is stepped into a motorway which develops to a rate of 10G and higher, and particularly with the rapid development of cloud computing and large data center transmission, a new generation of optical modules with higher speed, smaller volume and lower power consumption are required in the market. PAM (Pulse Amplitude Modulation) signals are a hot signal transmission technology for high-speed signal interconnection in next-generation data centers, and can be widely applied to electric signal or optical signal transmission of 50G/100G/200G/400G interfaces. The traditional digital signal adopts NRZ (Non-Return-to-Zero) signal at most, that is, 1, 0 information of digital logic signal is expressed by 2 amplitude levels, and each symbol transmits 1 bit information; the PAM4 signal may take 4 amplitude levels, with each symbol conveying 2 bits of information. Therefore, to achieve the same signal transmission capability, the symbol rate of the PAM4 signal only needs to be half of that of the NRZ signal, and the information amount transmitted with the same bandwidth is doubled.
Aiming at 50-200G test, a special PAM4200G four-channel error code analyzer (BERT) and 16 radio frequency lines of 40GHz (the difference lines need 16 radio frequency lines) of a single-channel test board packaged by QSFP28 are used for realizing the test of the PAM4 products, but the external PAM4200G error code analyzer is high in manufacturing cost and the market is 4-40 million dollars; meanwhile, 16 40G (2000 dollars minimum) radio frequency lines are required to be connected, the connection of the whole system becomes complicated, the cost of the system is high, 40G radio frequency lines which are longer than 1 meter are required in high and low temperature verification tests, the signal insertion loss is increased, and the eye pattern quality of the PAM4 module is influenced (wherein the more critical technical index is influenced, namely TDECQ is deteriorated).
The PAM4100G/200G SR4 AOC test is mostly realized by adopting two sets of schemes in figure 1, and also realized by adopting the scheme in figure 2. The cost, the system complexity and the software architecture difficulty are all multiplied, and the other two sets of equipment need 32 40G radio frequency lines, so that the system construction and maintenance bring great challenges.
Disclosure of Invention
In order to solve the problems in the prior art, the invention provides an industrial-grade PAM4200G error code testing device.
The invention comprises an MCU, a communication module, a digital signal processor, a temperature control module for controlling the temperature of the digital signal processor, a clock generator, a power module and a test board for testing a module to be tested, wherein the test board is provided with pins for enabling the module to be tested to be respectively communicated with the MCU and the digital signal processor, the output end of the MCU is connected with the input end of the temperature control module, the MCU is also respectively connected with the clock generator, the digital signal processor and the power module, the digital signal processor is provided with at least one group of communication channels connected with the module to be tested, a code pattern generator for testing the error rate and an error code detector connected with the code pattern generator.
The invention is further improved, the number of the test boards is 2, the test boards are used for testing a first module to be tested and a second module to be tested simultaneously, the industrial PAM4200G error code testing device further comprises a switch used for switching the communication between the MCU and the first module to be tested or the communication between the MCU and the second module to be tested, and the number of the communication channels is two.
The invention is further improved, the change-over switch is an I2C bus change-over switch, and the first module to be tested and the second module to be tested are communicated with the MCU through an I2C bus.
The invention is further improved, each group of parallel communication channels comprises four parallel communication channels, each communication channel outputs 26.56GBoud or 25.78Gbps, and 2 groups of parallel communication channels output 400 Gbps.
The invention is further improved, the temperature control module comprises a TEC controller and a TEC module, the digital signal processor is arranged on the TEC module, the input end of the TEC controller is connected with the output end of the MCU, and the output end of the TEC controller is connected with the TEC module.
The invention is further improved, the TEC module heats the TEC hot surface when positive pressure is applied, the TEC cold surface refrigerates when negative pressure is applied, the TEC hot surface is provided with the heat dissipation module, and the digital signal processor is fixed on the TEC cold surface.
The invention is further improved, the power module is a linear stabilized voltage power supply, and the output of the linear stabilized voltage power supply is controlled by the MCU.
Compared with the prior art, the invention has the beneficial effects that: the test method is used for testing the PAM450G \100G \200G \200G AOC optical module, and simultaneously supports working in an industrial-grade temperature range (-40-85 ℃), greatly reduces the cost of production equipment, and is suitable for being used in batch production of production lines.
Drawings
FIGS. 1 and 2 are schematic prior art structures;
FIG. 3 is a schematic structural view of the present invention;
FIG. 4 is a schematic diagram of the MCU circuit of the present invention;
FIG. 5 is a digital signal processor circuit schematic;
FIG. 6 is a schematic diagram of a clock generator circuit;
FIG. 7 is a schematic circuit diagram of a power module;
FIG. 8 is a schematic diagram of a TEC module circuit;
FIG. 9 is a schematic diagram of a two-way test board and a power circuit of the test board.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and examples.
As shown in fig. 3, the present invention includes an MCU104, a communication module, a digital signal processor 106, a temperature control module for controlling the temperature of the digital signal processor 106, a clock generator 103, a power module 110, and a test board for testing the module to be tested, wherein the test board is provided with pins for communicating the module to be tested with the MCU104 and the digital signal processor 106, respectively, an output end of the MCU104 is connected to an input end of the temperature control module, the MCU104 is further connected to the clock generator 103, the digital signal processor 105 and the power module 110, the digital signal processor 105 is provided with two sets of four parallel communication channels connected to the module to be tested, and is further provided with a code pattern generator for testing the error rate and an error code detector connected to the code pattern generator.
The embodiment is a two-way test device, the number of the test boards is 2, the two-way test device is used for simultaneously testing a first module to be tested 107 and a second module to be tested 108, and the industrial-grade PAM4200G error code test device further comprises a switch 109, and the switch is used for switching the communication between the MCU and the first module to be tested 107 or the communication between the MCU and the second module to be tested 108. The present example also allows for the testing of 3 or more PAMs 4 at the same time, as the DSP processor 105 performance allows.
As one embodiment, the switch in this example is an I2C bus switch, and the first module under test 107 and the second module under test 108 communicate with the MCU through an I2C bus.
The temperature control module of this example includes a TEC controller 102 and a TEC module105, the digital signal processor 106 is disposed on the TEC module105, an input end of the TEC controller 102 is connected to an output end of the MCU104, and an output end of the TEC controller 102 is connected to the TEC module 105.
As shown in FIGS. 4-9, the invention simultaneously realizes two functions of a PAM4 code pattern generator and a PAM4 error detector, is used for testing PAM450G \100G \200G \200G AOC optical modules, and simultaneously supports working in an industrial-grade temperature range (-40-85 ℃). The functions of the modules are explained in detail as follows:
1. the invention sets two PAM4 QSFP28 packaging channels, introduces two module power supplies to supply power for the channels, equivalently integrates two PAM4 QSFP28 test boards, can be simultaneously inserted into two PAM4 QSFP28 packaged modules to carry out parallel test (107 and 108), and supports the speed from 50G to 200 Gbps.
2. And the digital signal processor 106 adopts a DSP (digital signal processing) chip to replace an external error code instrument, 8 channels output in parallel, each channel outputs 26.56GBoud (baud rate) or 25.78Gbps (rate), and the total output is 400 Gbps. The digital signal processor 106 supports the free switching of NRZ (non return to zero code) and PAM4 (4-level pulse amplitude modulation) signals, the code pattern generator RBS7\ PRBS9\ PRBS13\ PRBS15\ PRBS23\ PRBS31, and simultaneously supports the code pattern necessary for testing PAM4 products: PRBS13Q \ PRBS15Q \ PRBS31Q \ SSPRQ, and the test of the product eye diagram index such as TDECQ is realized; the receiving error code detector also supports the code pattern of the transmitting part, and the error code rate test (sensitivity test) of the product is realized.
3. Digital signal processor (DSP processor) 106: the clock output CLK OUT supports 2/4/8/16/32/64/18 clock frequency with 7 frequency divisions, such as 25.78Gbps, the clock can output 12.89 frequency, so that a precise reference clock is provided for the sampling oscilloscope to perform eye Pattern test, the reference clock is higher, code Pattern locking (Pattern Lock) is facilitated, and the eye Pattern test efficiency is higher and more precise.
4. USB-B101: the communication module of the embodiment adopts USB communication, realizes data interaction between the device and a computer (PC) through a USB-B101 interface, and forms a finished test system by matching with upper computer software and a communication protocol.
5. MCU 104: the micro control unit simulates a Human Interface Device (HID) and realizes data interaction through USB and computing communication; data interaction is realized with the digital signal processor 106 through an MDIO bus; data interaction with two modules to be tested 107 and 108 is realized through an I2C bus and an I2C SWITCH (change-over SWITCH) 109; setting the DAC output through a software PID, and controlling the output voltage of the TEC controller 102 to control the TEC module 105; CLOCKGEN (clock generator) 103 is set by I2C.
6. TEC Controller (TEC Controller) 102: the TEC control circuit of 3A, USB-B104 interface, adjusts the output of TEC controller 102 via software PID setting output DAC (digital to analog converter) to control the temperature of TEC MODULE 105.
7. TEC Module (TEC Module) 105: the TEC temperature is controlled by reading the monitored temperature of the DSP processor by adopting a digital PID, the example adopts a 9W/3A TEC (thermal electric Cooler), the hot surface of the TEC generates heat when positive pressure is applied, the TEC is used as the cold surface of the opposite surface of the hot surface for refrigeration when negative pressure is applied, the refrigeration power reaches 9W, the temperature difference between the cold surface and the hot surface can reach 70 ℃, the low temperature can reach-30 ℃, and the example adopts a certain area of radiating fins on the hot surface of the TEC for the purpose of just radiating heat. The DSP chip of the embodiment is fixed on the cold surface of the TEC module105, when the ambient temperature exceeds the commercial-grade temperature range (0-70 ℃) and the temperature monitored by the digital signal processor 106 is lower than 10 ℃ or higher than 60 ℃, the MCU (104) controls the DAC to adjust the output voltage of the TEC controller 102 through software PID to realize the temperature rise and the temperature drop of the TEC, and the temperature of the DSP shell is ensured to be between 10-60 ℃, so that the DSP chip is ensured to be in the optimal working temperature range.
8. CLOCK GEN (CLOCK generator) 103: the MCU I2C bus configuration specifies the output clock frequency, e.g., 156.25MHz, provides a clock reference to the DSP processor 106, enables the DSP processor 106 to operate normally and output the specified NRZ or PAM4 signals, and enables the error detector to lock the input signal for error detection.
9. QSFP28 PAM4 DUT (PAM 4 module to be tested) 107/108: two PAMs 450G-200G QSFP28 package modules, namely tested modules.
10. I2C SWITCH (I2C channel SWITCH) 109: the MCU needs to SWITCH an I2C bus through an I2C SWITCH 109 and respectively communicates with the modules 107\108, so that data interaction between the modules and the MCU is realized.
11. LDO (linear regulated power supply) 110: four voltages of 3.3V \1.8V \1.0V \0.75V are output to provide a low-noise power supply for each circuit.
The invention has the following innovation points:
1. the device designs two PAM4 QSFP28 packaging channels, which is equivalent to integrating two PAM4 QSFP28 test boards, can be simultaneously inserted into two PAM4 QSFP28 packaged modules for parallel testing (107 and 108), supports the speed from 50G to 200Gbps, and improves the production efficiency;
2. the code pattern generator and the error detector are integrated through the DSP processor, 8 channels output in parallel, each channel outputs 26.56GBoud (baud rate) or 25.78Gbps (rate), and the total output is 400 Gbps. The DSP 106 supports the free switching of NRZ and PAM4 signals, the code pattern generator RBS7\ PRBS9\ PRBS13\ PRBS15\ PRBS23\ PRBS31, and simultaneously supports the code pattern necessary for testing PAM4 products: PRBS13Q \ PRBS15Q \ PRBS31Q \ SSPRQ, and the test of the product eye diagram index such as TDECQ is realized; the receiving error code detector also supports the code type of the transmitting part, so that the error code rate test (sensitivity test) of the product is realized, expensive error code instrument equipment is replaced, at least 4 million dollars (domestic PAM4200G error code instrument) are saved for each equipment, and more than 40 million dollars (American PAM4 error code instruments, such as Keysight M8040A single-channel 32G error code instruments) are saved at most, the cost of production equipment is greatly reduced, and the method is suitable for batch production of production lines;
3. the device does not need to use 32 radio frequency wires with 40GHz as many as one, and only needs one connection oscilloscope to trigger, so that the radio frequency cost is reduced by 32 times, and meanwhile, the system connection is very simple, and the system is very easy to build and maintain;
4. the MCU104 is used for controlling the 3.3V output voltage and current of each path of the LDO 110, and a module current test and an output voltage bias test (such as the output voltage of any point such as 3.1V,3.3V,3.6V and the like, the precision reaches 5mV) can be realized without using an external expensive program control power supply, so that the voltage bias tests such as DVT, EVT and the like in the product research and development stage are met, the equipment cost is saved, and the test efficiency is improved;
5. the device realizes the interaction between the MCU104 and the computer data through a USB-B101 interface, adopts an HID communication mode, does not need to be driven, is plug and play, and is compatible with all WINDOWS systems, such as 32 and 64 bit operating systems like WINDP, WIN7, WIN10 and the like, aiming at the current mainstream operating system WIN10, all drivers need to purchase digital signatures to be installed, and the device does not need to be driven, so the equipment development cost is also reduced;
6. this device size is only 211mm 107mm, and is small, and weight is only 200 grams, and greatly reduced area on the testboard makes the testboard become succinct, the high utilization.
The above-described embodiments are intended to be illustrative, and not restrictive, of the invention, and all changes that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.
Claims (7)
1. An industrial-grade PAM4200G error code testing device is characterized in that: including MCU, communication module, digital signal processor, carry out temperature control's temperature control module to digital signal processor, still include clock generator, power module and be used for testing the survey test panel of module that awaits measuring, wherein, be equipped with on the survey test panel and be used for making the module that awaits measuring respectively with the pin of MCU and digital signal processor communication, the MCU output links to each other with the temperature control module input, MCU still links to each other with clock generator, digital signal processor and power module respectively, digital signal processor is equipped with at least a set of communication channel of being connected with the module that awaits measuring, still is equipped with the code pattern generator that is used for the error rate test and the error code detector that links to each other with the code pattern generator.
2. The industrial-grade PAM4200G error code testing device of claim 1, wherein: the number of the test boards is 2, the test boards are used for simultaneously testing a first module to be tested and a second module to be tested, the industrial PAM4200G error code testing device further comprises a selector switch used for switching the MCU to communicate with the first module to be tested or the MCU to communicate with the second module to be tested, and the number of the communication channels is two.
3. The industrial-grade PAM4200G error code testing device of claim 2, wherein: the change over switch is an I2C bus change over switch, and the first module to be tested and the second module to be tested are communicated with the MCU through an I2C bus.
4. The industrial-grade PAM4200G error code testing device of claim 2, wherein: each group of parallel communication channels includes four parallel communication channels, each outputting 26.56GBoud or 25.78Gbps, and 2 groups outputting 400Gbps in total.
5. The industrial-grade PAM4200G error code testing device according to any of claims 1 to 4, wherein: the temperature control module comprises a TEC controller and a TEC module, the digital signal processor is arranged on the TEC module, the input end of the TEC controller is connected with the output end of the MCU, and the output end of the TEC controller is connected with the TEC module.
6. The industrial-grade PAM4200G error code testing device according to claim 5, wherein: the TEC module heats the TEC hot surface when positive pressure is applied, the TEC cold surface refrigerates when negative pressure is applied, the TEC hot surface is provided with the heat dissipation module, and the digital signal processor is fixed on the TEC cold surface.
7. The industrial-grade PAM4200G error code testing device according to any of claims 1 to 4, wherein: the power supply module is a linear stabilized voltage power supply, and the output of the linear stabilized voltage power supply is controlled by the MCU.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN113938191A (en) * | 2021-10-26 | 2022-01-14 | 武汉光迅科技股份有限公司 | Method and device for parameter testing of optical module |
| CN113985750A (en) * | 2021-09-30 | 2022-01-28 | 中国兵器工业集团第二一四研究所苏州研发中心 | Interface circuit board level integrated circuit board |
| CN115765865A (en) * | 2022-11-09 | 2023-03-07 | 绍兴中科通信设备有限公司 | 100G high-speed optical module three-temperature adjusting and testing system with flow test function |
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| CN115765865A (en) * | 2022-11-09 | 2023-03-07 | 绍兴中科通信设备有限公司 | 100G high-speed optical module three-temperature adjusting and testing system with flow test function |
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