Parallel Optical Interconnects With MPO Fiber

While early optical connector and cabling solutions themselves provide advantages over copper,more recent optical solutions extend this advantage considerably.In the mid-1980s，optical fiber was introduced into data prossing communications.At regularintervals,suppliers debeloped higher density connectors in lockstep with optical transceiver manufacturesand original equipment manufacturers (OEMs).Multifer connectors have been developing for some time.Early ESCON connectors were quite bulky for handling two fibers.Denser solutions such as the MPO connector allowed the same two fibers to be contained in less linear space.Liner board space.Linear board space,though,is not the appropriate measurement of density.To make the most efficient use of the available space ，designers can resort to multirow fiber arrays in which one has to think in two dimensions (width and height).As a result,the same MPO connector has been expanded to contain 72 fibers in the same liner space as was occupied by only two fibers.Recent Electrotechnical Industry Association/Telecommunications Industry Association(EIN/TIA) standards proposals call for arrays of up to 96 optical fibers contained in this same size connector,and technical proposals postulate over 250 fibers in the same linear space.

The resulting improtant metric is the toal mating density(TMD)for a given total mating area (TMA)。A two-dimensional(2-D) connector can greatly increase TMD.A two-fiber MPO connector would,for example ,have a TMA of 3.0x 5.0mm=15mm^2 and thus a TMD of 2 fibers/15mm^2 and thus a TMD of 2fibers/15mm^2=13 fibers/mm^2.Conbersely,a 72-fiber MPO style connector has 6 rows of12 fibers for a TMD of~4.8 fibers/mm^2.While the transition from an ESCON connector an MPO connector increased fiber density by only a factor of about 2.5,the transition from two fiber MPO connector to 2-D MPO conectors has increased fiber of 90 times over the past 20 years, driven largely bu the move to 2-Darrys.

MTP MPO Fiber Cable is offered for various applications for all networking and device needs like 100 Gig modules. It uses a high-density multi-fiber connector system built around precision molded MT ferrule. Fiberstore’s mpo fiber cable are available in UPC and APC finishes, support both multimode and single mode applications, and optional lengths available. Our MPO/MTP fiber cable is with push connector IEC 61754-7 and TIA/EIA 604-5A compliant and offer low cost per termination for high density applications. The MPO/MTP fiber cables are tested with guaranteed quality, and they can be installed easily, which saves time and money.

By themselves thees dense connector solutions can greatly simplify structured cabling solutions by aggrgating fibers in systems employing traditional serial or small parallel fiber optic transceibers in systems employing traditional serial or small parallel fiber-optic tranceivers. The increased cabling density can directly reduce the space demands of systems.With properly designed optical can provide very reliable and consistent assembly process,high-density optical assemblies can provide very reliable and repeatable performancd,meeting the needs of the server and storage community.Compared with copper interconnections,these is a dramatic size and weight savings and a cost benefit,Considering these factors alone,one can build a strong case in favro denser optical conneections.Howerver,interfacing these dense connectors directly with corresponding dense energy -efficient active optical can result in the major benefit of increasing board channel density while simultaneously lowering the cooling requiremnts.

Cost-effective multimode polymer waveguides, suitable for use in high-speed on-board optical interconnections, are presented. The fundamental light transmission properties of the fabricated waveguides are studied under different launch conditions and in the presence of input misalignments. Low loss (~0.04 dB/cm at 850 nm) and low crosstalk (<-30 dB) performance, relaxed alignment tolerances (plusmn20 mum) and high-speed operation at a 10-Gb/s data rate are achieved. No degradation in the high-speed link performance is observed when offset input launches are employed. Moreover, a range of useful waveguide components that add functionality and enable complex on-board topologies are presented. The optical transmission characteristics of the fabricated components are investigated and it is shown that excellent performance is achieved. Excess losses as low as 0.01 dB per waveguide crossing, the lowest reported value for such components, and bending losses below 1 dB for 90-degree and S-shaped bends are obtained even with multi mode fiber optic cable . Moreover, high-uniformity power splitting and low-loss signal combining are achieved with Y-shaped splitter/combiners while a variable splitting ratio between 30%-75% is demonstrated with the use of multimode couplers. Overall, the devices presented are attractive potential candidates for use in on-board optical links.

Optical interconnect is a way of communication by optical cables. Compared to traditional cables, optical fibers are capable of a much higher bandwidth, from 10 Gbit/s up to 100 Gbit/s.The technology is currently being introduced as a way to link computers to mobile devices, as well as on motherboards and devices within computers.

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Fiber Patch Cord Power Loss Measurement

Fiber Patch Cord Power Loss Measurement,Multimode patch cord optical loss power measurement is performed using the steps described in ANSI/TIA-526-14,method A. The patch cord is substituted for the cable plant. Becausepatch cords are typically no longer than 5m, the loss for the optical fiber is negligible and testing can be performed at 850nm or 1300nm. The loss measured in this test is the loss for the patch cord connector pair. ANSI/TIA-568-C.3 states that the maximum loss for a connetor pair is 0.75db.After setting up the test equipment as described in ANSI/TIA-526-14, method A, clean and inspect the connetors at the ends of the Fiber Patchcord to be tested. Verify that your test jumpers have the same optical fiber type and connetors as the patch cords you are going to test. The ANSI/TIA-526-14 being used for testing. Ensure that there are no sharp bends in the test jumpers or patch cords during testing.Because both patch cord connectors are easily accessible, optical power loss should be measured in both directions. The loss for the patch cord is the average of the two measurements. If the loss for the patch cord exceeds 0.75dB in either direction, the patch cord needs to be repaired or replaced.Connector insertion loss measurement isolates the loss of a single connector on a cable assembly. It may be referred to as connector loss. Many time cable assemblies are shipped from the manufaturer with the insertion loss for each connetor listed on the packaging. The package shown in Figure 33.37 contains a duplex multimode patch cord. In the upper-left corner of the package, a label lists the insertion loss measurements for each connector.Connector test jumper 1 as shown earlier in Figure 33.31. Record the optical power displayed by the optical power meter. This number is the reference power measurement. This number is typically around -20 dBm with a 62.5/125μm multimode optical fiber and -23.5dBm with a 50/125μm multimode optical fiber. These numbers can vary from OLTS to OLTS. The following are 62.5/125μm and 50/125μm multimode fiber from fiberstore, picture is below:SC-SC Plenum Duplex 62.5/125 sc multimode, with SC to SC termination, this fiber optic patch cable is specificially designed for ethernet, multimedia, or communication applications. The SC connector features a push-pull locking system. The plenum rating provides the fire protection required to run this cable within walls and air plenums without using conduit. The patented injection molding process provides each connection greater durability in resisting pulls, strains and impacts from cabling installs.lc lc multimode has a bayonet-style housing and a long spring-loaded ferrule hold the fiber. They are available in both multimode or singlemode versions. Horizontally mounted simplex and duplex adapters are available with metal or plastic housing.

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Cabling Configuration for A Basic Fiber Optic Network

Cabling Configuration for A Basic Fiber Optic Network,each end of a duplex ST multimode should identify position A and postion B .This is typically accomplished with raised lettering on the latch that holds together the two connectors at each end of the patch cord.A raised letter on the latch holding together two SC connector is shown in Figure 17.29.Because of the physical size on an SC connector,the raised lettering is easy to read. However,this is not the case with small form factor connectors such as the latched LC pair shown in Figure17.30


There are some related duplex sc-sc patch cord from our store, the following picture, you can see.



This is an "Yellow" single-mode cable with a 9 μm core and 125 μm cladding diameter. The cable has a color-coded Dual SC connector on each end. Cost-effective solution that provides high bandwidth and transmission rates over longer distances. With SC to SC termination, this high-quality fiber optic patch cable is specifically designed for Gigabit Ethernet applications. The patented injection molding process provides each connection greater durability in resisting pulls, strains and impacts from cabling installs.

The first step in verifying the polarity of the chanels shown in Figure17.28 is to de-enrgize the equipment at both ends of the network,Since lathced duplex patch cords are used,unlug both connectors from both ends of the patch cords at each of the network.Using the continuity tester,verify that connectors on each end of a patch cord are oriented so position A goes to positionB .You can do so byinserting the ferrule of the A position connector into the continuity teseter as shown in Figure17.31.

With the connecetor inserted,energize the continutity tester and check to see if light is exiting the optical fiber in position B at the oppotite the path cord.if light is exiting the optical fiber in position B,the polarity is correct.if ligtht is exting the optical fiber in position A,the polarty is not correct.With the continuity tester still attached and energized ,unlatch both conectors,seap locations,and relatch.Verify light is extiing forem the optical fiber in positon B.Repeat this for the other fiber optic patch cords and correct as necessray.

With both patch cords properly configred,the next step is to verify the polarity the horizontal cabling .To minimize accses to other horizontal cabling,you should work from the equipment outlet to the pach panel.REmove the cover of the equipment outlet and plug both connectors at one end of the path cord into the receptacles on the equipment ontlet.Do not disturb the horionta cabling connections.

Insert the ferrule of the A postion connector at the end of the patch cord into the continuity tester as shown earlier in Figure17.31.With the connector inserted,engrgize the continuity tester as shown earlier in Figure 17.31.With the conector inserted,energize the continuity teser and check to see if light is exiting the horizontal cabling optical fiber in positionB at the pach panel.If light is exiting the optical fiber in postion B,the polarity is not correct.With the continuity tester still attached and energized,unlatch,Light should be exiting from the optical fiber in positionB.Reinstall the equipment outtlet cover.

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Rock Style Chrome Hearts Ring

In addtion to diamond rings, there are a lot of other options out there to consider, such as handmade silver rings. They're fashion, lovely, and they don't all come with the baggage of a diamond—especially, they're not as expensive. More and more people choose to buy the rings online now.

Engagement rings and wedding rings sold at store are 20 percent more expensive than that from online. That's because you're not paying the extra overhead costs of traditional retailers. The online jewelry and watch industry has grown to $9.8 billion, increasing an average of 2.9 percent a year for the past five years, according to IBISWorld, an industry research firm. And online retailers, for example, Chrome Hearts, usually have more styles to choose from than their physical rivals.

Chrome Hearts rings Feature

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2.5G SFP optical module development of high-performance general scheme

1. working principle of the module

Long-range fiber optic sfp module products for unity with APD receiver module, work rate 2500Mbps, transmission distance 80km, electrical interface can hot swap without power, dual LC optical interface plug type, with DDM digital diagnostic functions. Transmitter and receiver module is divided into two parts. LC driven in part by an integrated emission control circuit with APC and DFB-LD components. The integrated circuit receiving LVPECL logic level signal and provide for the LD bias and modulation currents, APC loop current size according to the size of the generated light emitted optical power LD, to achieve automatic control of emitted light power work can be. The integrated circuit with a transmitter shutdown; receiving section includes APD TIA components and limiting amplifier chip. CML limiter amplifier output logic level signal and a signal having a LOS alarm function.

2.5 G electric modulation signal, through TD difference data input feet enter into the light module launch part, through the module within the Laser Driver produces light modulation signal data, through the optical fiber transmission.Optical signal to receive data, through the optical module will receive part of the light signal into electrical signal modulation and shaping amplifier, in through the module of Rx difference data feet output.So as to realize the long-distance transmission of data through the optical fiber.

2. based on SFP-MSA Multi-Source Agreement design

SFP-MSA Multi-Source Agreement sets out our main design SFI 'need to meet the mechanical dimensions, package, module definition and application circuit Goldfinger peripheral module inserted row, making it compatible with a wide range in the optical communication equipment. According to the requirements of the agreement, we have designed single mode fibre sfp housing meets the requirements of the agreement.

3. Based on the design of SFF-8472 standard

SFF-8472 standard defines the main multi mode sfp digital diagnostic functions and modules to achieve the principles of internal software storage spaceStandard definition, making the system vendors through MOD-DEF modules (0) ~ MOD-DEF (2) of the three legs of the operating parameters of the software control module for real-time monitoring.

 

According to the definition of this standard, thismulti mode sfp designed to its operating voltage (reported accuracy of ± 3%), operating temperature (reported accuracy of ± 3 ℃), transmitted optical power (reported accuracy of ± 3dB), transmit bias (reported accuracy of ± 10 %), received optical power (reported accuracy of +3 dB) for real-time reporting, enabling the SFP digital diagnostic functions.

4. light-emitting device selection

Because the module work rate reached 2.5G, transmission reach 80km and small packages. So we use the LC 1550nm DFB laser with coaxial isolators as emitting device according to the design. (1) DFB device characteristics: DFB lasers belongs to a single longitudinal mode (SLM, Single LongitudinaL Mode) semiconductor lasers. Compared SLM semiconductor lasers with Fabry-Perot laser, it is no longer independent of the resonant cavity loss pattern, but different vertical mold design paired with different losses.

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Design principles and implementation of multi-function monitoring platform SFP optical module

Read by the microcontroller optical modules and CDR-related memory, and in accordance with the parameters that need to be read LCD display real-time, so that the results intuitive and easy to understand. While connected via serial port and external facilitate debugging. In this system, SFP module implemented by CDR I2c bus communication with the microcontroller. fiber optic transceiver module via an external device access signal, the photovoltaic modules into an electrical signal, and then after the clock data recovery CDR, bit error rate, measuring extinction ratio, sensitivity and other parameters with normal test results to see whether the correct comparison. While the optical module is connected via the optical interface with external microcontroller to communicate with the outside world through the serial port for data exchange, each signal via SMA connector leads, as required by coaxial cable to connect the debugger, it is easy to debug.

2.2 optical module monitoring platform software design

2.2.1 software system design structure with a brief description of the microcontroller Atmega128L LCD (Model LM16032) using parallel data transfer, three control bit MCU PA5 ~ 7 and LCD (RS, RW, E) is connected, plus two control LCD display on the Up-key and turn the key down key DownKey and SCM PE5 and PE6 connected to the microcontroller interrupt the way to achieve the appropriate control. SFP microcontroller reads the data from the relevant parameters I2c bus after transmission through parallel to the LCD display. Using the timer mode, so With a frequency greater than 24MHz refresh LCD display.

3 main parameters read

3.1 Temperature parameters read

Because of the module can be used in a high rate of system and has the appearance of small, the layout of the they are usually very compact.In these applications sfp transceiver of rectangular box shape affect the cooling air flow, thus partially weaken the advantages of easy to use, so the temperature inside the module as a useful parameter to measure the long-term stability of the device and device of electro-optic specifications conform to the degree of life.3.2 read voltage parameterIn the SFP working voltage can through sensor installed on the internal PCB circuit for measuring.These measurements can also be used to observe the working voltage drift.And according to the experience can be linked with a given SFP pin or monitoring failure due to the system power supply environment caused by the large voltage fluctuation.

3.3 Read bias current

When reliability prediction has been the most effective transceiver module parameter is the laser bias current, typically used in integrated optical transceiver modules are in constant optical output power mode. Through a closed loop feedback circuit to change the laser bias current so as to stabilize the laser output power. Since the laser efficiency and the threshold values ​​are changed with temperature, and many modules are required to change the laser bias current so as to stabilize the optical output power of the laser, the laser bias current if the variation is not as temperature or voltage changes caused, it shows that the laser potential stability problems.

4 Based on the test platform module parameters

4.1 Bit Error Rate Test

For error test mainly through error instrument, optical module, and the CDR from ring, through error instrument observation error rate is less than 1 hour 10-12.Test procedures and results 1) good connection test equipment.(2) the work continuously for an hour, once every five minutes record error rate.(3) the bit error rate has been less than 10-12.

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The basic principle and function of multifunctional SFP digital diagnosis

In recent years, fiber optic communications network has achieved rapid development. Optical transceiver module as one of the key technologies of optical fiber communication network is widely used in a variety of optical communication systems. Smart SFP optical module, which uses digital diagnostic functions fiber optic sfp module, it can achieve real-time monitoring of network management unit transceiver module temperature, supply voltage, laser bias current, and optical power transmission and reception. The measurement of these parameters can help identify the location management unit fiber link failure occurs, simplify maintenance, improve system reliability. Optical modules to achieve real-time monitoring capabilities for effective life prediction module, isolation system failures, as well as to verify the correctness of the module status during the installation and commissioning of high practical value. The author based digital diagnostics, design and implement a monitoring platform of an optical module. The platform uses the microcontroller via a 2-wire serial bus to access the modules to read and deal with related parameters, while module parameters to be read in real time through the LCD display. And with CDR (clock data recovery) section, can signal clock recovery and data retiming, as a basis for hardware monitoring module in the relevant technical specifications designed monitoring platform.

1.1 the basic principle of digital diagnosis

In the SFF-8472MSA, the specification of the digital diagnostic functions and related SFF-8472 for details. The specification, in the northern part of the circuit board module detection and digital signal parameters. Then, provide calibrated results or provide digitized measurements and calibration parameters. This information is stored in standard memory results in order to read through the two-wire serial interface. Retained the originalbidi sfp transceiver / GBIC Address Address A0h at the map and added a 256-byte storage unit at the address A2h SFF-8472 in the agreement. This information is stored in addition to providing parameters to detect, but also defines the alarm flag or alarm conditions, the state of the mirror each pin, limited number of control and user-writable storage unit.

1.2 The role of digital diagnostics

(1)intelligent life prediction 10g sfp module provides a prediction methods of the parameters of the laser degradation of real-time monitoring.Light module within the light power feedback control unit will power output control at a stable level, power control is by increasing the laser Tx_Bias (offset current).Therefore, we can through the monitoring of the laser bias current can be used to predict the life of the laser.

(2) fault location In optical links, the location of the fault occurs is critical to business fast load positioning.Fault location, need comprehensive analysis of status, a pin and measuring parameters.Through to the detected Tx_power (sending power), Rx_power (received power), Temp (temperature), Vcc (voltage), Tx_Bias (offset current) warning and alarm status, Tx Fault image of the state variables (alarm) and RxLOS (receiving signal loss), and other information for comprehensive analysis, can locate the Fault is in the module or on the lines, in local module or in the remote module.

(3) compatibility verification by monitoring the voltage is outside the specified range, whether the received optical power overload or below the receiver sensitivity, temperature exceeds the operating temperature range, etc., work environment analysis module meets the data sheet or compatible with the relevant standard.

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Fashion Sunglasses 2014

The thing is that sunglasses appears on our face and it's our visit card, as we showcase our overall style and look, that's why it's very important to show people our knowledge about fashion and trends that we follow. For the ones pursuing fashion, sunglasses is the same as bags, hats, shoes and clothes , are being changed every season every year. These days sunglasses and Chrome Hearts optical glasses frames are coming in various colors and shades. New 2014 season offers different styles, sizes and shapes. What sunglasses are look like in 2014? Look here — photos of the most stylish newChrome Hearts Sunglasses 2014.

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Design and Research of Intelligent SFP optical module

Introduction

In the optical communication products, optical module occupies has a very important position. Optical transceiver module as one of the key technologies of optical fiber communication network, is widely used in synchronous optical network SONET) and Synchronous Digital Hierarchy SDH), Asynchronous Transfer Mode (ATM), Fiber Distributed Data Interface (FDDI), as well as Fast Ethernet and thousands Gigabit Ethernet and other systems.

In the present optical communication products, fiber optic transceiver module has been more popular than others, SFP GBIC module module volume ratio reduced by half, but also supports hot-swap capabilities, has been widely used. Meanwhile, in the various existing networks needed optical transceiver module types, more and more requirements are also increasing. To meet the ever increasing performance requirements of the system,Optical module continues to develop intelligent, fast and high-density interconnect direction.

Intelligent SFP optical modules, namely USES the fiber optic sfp module of digital diagnosis function, will become a new generation of optical transceiver module integrated in the window.It can realize network management unit real-time monitoring the temperature of the transceiver module, power supply voltage, bias current, as well as the transmitting and receiving optical power.Through monitoring of these parameters, we can help system administrators predict the life of the light module, fault isolation system and authentication module in the installation of compatibility, etc.

A smart SFP optical module system design

1.1

Transmitting section

The main role of the light-emitting process in the optical transmission module is to convert the optical signal into an electrical pulse signal is a pulse, the electrical signal is input, the output optical signal. Transmitter module, mainly by the laser driving circuit and the TOSA. Which TOSA backlit by the laser diode LD and PD components. LD is used in vertical cavity surface emitting laser VCSEL.

First electrical modulation of the laser drive lasers to meet the input digital fiber optic communications system required drive signal, the drive signal from the bias current IbiasAnd the modulation current Imod composition, the laser emits an optical signal corresponding to the driving of the driving signal, the optical signal is coupled into the optical fiber and transmitted to the receiving end. In this scenario, the laser driver selection MAX3286.

Laser driver with the functions of automatic power control (APC), APC circuit using the backlight diode in the TOSA, monitoring laser the size of the backlight.When the optical power is less than one rating, through increase the drive current feedback circuit, laser output power increases as the rated power value.Conversely, if the optical power is greater than a certain rating, is through feedback circuit reduce drive current, laser power output is less.APC circuit can dynamically adjust the laser power, therefore, the size of the bias current, can automatically compensate laser due to the change of ambient temperature or aging caused by the change of the output optical power, keep the output optical power range is relatively stable.

1.2

Receiving part

The main role of the receiver module is attenuated after

deformation weak optical fiber cable transmission signal to a pulse electric pulse signal by photoelectric conversion, and give sufficient amplification, a standard reduction of the digital pulse signal. Optical receiver module schematic shown mainly by the photodiode PD, a preamplifier, a limiting amplifier and other components. Which photodiode and preamp integrated package together constitute ROSA.

 

A photodiode is a core device of a digital optical receiver, an optical pulse signal will be the electrical pulse signal by photoelectric conversion, commonly used are PIN photodiodes and avalanche photodiode APD. Optical signal from the optical interface enters the photodiode PD, is converted into a weak current, the current through the pre-amplifier and converted into a voltage level is amplified to an appropriate level.

Effect limiting amplifier output of the preamplifier is the magnitude of different amplitude analog signal into a digital signal, these signals can be amplified. To photoelectric detectors with a good match and get the low-noise and wide-band preamplifier gain is not too high, the preamplifier output voltage amplitude is usually from a few millivolts to tens of millivolts, such small signals can not be directly output optical module is therefore necessary to further enlarge the signal; the other hand, the photodetector detects the light signal from the amplitude of the current signal in a defined tolerance level, the tolerance limits of the capacity of the fiber considered Poor, splice loss and the parameter fluctuations caused by temperature and aging, however, the data for further processing, the signal amplitude is preferably a constant value.

Therefore, limiting amplifier requires a certain dynamic range, which usually requires a dynamic range of more than 20dB.

1.3

Digital Diagnostics DDM part

Digital diagnostics mainly composed of MCU to complete. By temperature MCU, the network management unit may receive real-time monitoring module, the power supply voltage, laser bias current and the light emitting and receiving power. By measuring these parameters, the management unit can quickly identify the specific location of fiber link failure occurs, simplify maintenance, improve system reliability.

Five DDM parameter acquisition circuit for acquisition by the first conversion, the inputs to the ADC, ADC five circuit analog voltage into a digital signal sent by the decoder circuit is stored in a memory support DDM corresponding address bit . Transmission of information via a two-wire serial interface (SCL clock line and data line SDA) to achieve.

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PCB simulation design of Gigabit SFP optical transceiver high-speed circuit

High-speed digital circuit design means that if the rise time of the signal propagation delay times of less than 4, PCB.The signal on the board can present transmission line effect, such a design is called high speed digital circuit design.And the Series digital circuit design method is different, high speed digital design need SI simulation analysis.SI simulation analysis generally divided into before wiring two process simulation and post layout simulation, its main task is found in the system design process and improving the sI problems, ensure the quality of signal transmission functions and the right time, is to ensure that the key step in the design is successful.

Gigabit SFP optical signal transceiver card is mainly composed of four modules: (SFP) fiber optic transceiver module, the large capacity data cache (SDRAM) (PCI9656), PCI bus interface module, control module (FPGA).Implementation of main function is to be able to send and receive gigabit Ethernet optical signals, on the physical layer and data link layer handling gigabit Ethernet protocol, IP packets and through PCI bus is extracted in the computer's memory.Demand support vet2 PCI card. Agreement support DMA transfer mode, data transfer rate is not less than 125 MB/s.

Light module in the design of input and output electric signal frequency up to 1.25 Gbps, using the LVPECL difference signal, the gigabit difference signal simulation discussed in literature [3].First of all, establish simulation model as shown in figure 7.Single line impedance 50 1000 f2 differential impedance (X1), signal rate of 1.25 GHz.Outl LVPECL difference output IBIS model for sfp transceiver module, Inl for FPGA LVPECL differential input IBIS model.

Design by using based on SI simulation analysis and design of high-speed signal PCB wiring rules, solved the gigabit sfp ports signals in the process of sending and receiving card design, signal integrity problems of cloth plate a successful, completely meet the requirement of design index, and avoid the repeat design from the signal integrity issues.In the process of high speed digital circuit design, based on SI simulation analysis early in the design of the product as much as possible to solve the signal integrity problems, so as to minimize the product cost, shorten the development cycle.

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