Semiconductor Technologies for Optical Interconnection From Ultra Long Haul to Very Short Reach  

Optical Networks Universe Photons rather than electrons will increasingly carry information in our daily lives. This trend began in the telecom and datacom industries and now optical interconnections connect continents and cities together almost exclusively. It continues in enterprises that are replacing copper infrastructure with high speed optical interconnects in their corporate networks: employees not only require more storage and access to key information but also supercomputing clusters with datacenters require high speed inter-processor communications to more efficiently determine information and run simulations. The trend, continually driven by greater bandwidth needs, now also extends to connecting faster multi-core microprocessors with attached RAM devices and storage interfaces. Today, driven by the increasingly sophisticated needs of the digital media consumer we see this trend poised to enter the multi-billion dollar consumer

Current Optical Networks Overview The Internet now consists of Wide Area Networks (WAN) spanning continents and oceans and connecting many more Metropolitan Area Networks (MAN). The adoption of optical interconnection has been swift in these networks as a result of fiber’s superior long distance performance. Although traditionally, copper has had the competitive edge in shorter distances of less than 100 meters (resulting from a lower total cost of ownership and greater familiarity with the technology), recent technological advances quickly challenge the long term merits of copper. Furthermore, fiber consistently out-performs copper in long distances (speed, bandwidth, attenuation, maintenance, cost and resistance to EMI). These advances coupled with the need for increasing data rates, are leading enterprises, previously the bastion of copper based LANs (Local Area Network), to deploy optical interconnect within their own LAN and SAN (Storage Area Network) infrastructure.

Wide Area Networks Overview WANs span distances of more that 400km and are segmented into “Ultra Long Haul” networks connecting continents with 1000km+ submarine optic fibers and “Long Haul” networks connecting metropolitan areas within a single continent with 400km+ terrestrial optic fibers. Usually, data within these networks are transmitted using a simple digital format called “NRZ” (Not Return To Zero) where a ‘1’ is transmitted as the laser is on and ‘0’ is transmitted as the laser is off. Though sufficient in the past, this simple modulation scheme cannot fully sustain increasing bit rates (now beyond 10Gb/s). Advanced modulations

  

techniques [Ref.1] are adopted in this case, allowing the data signal to withstand high speed issues such as attenuation, chromatic and polarization mode dispersions and self and cross phase modulation.

Furthermore, traditionally WANs have been deployed by telecommunication companies which adhere to robust telephony communication standards such as Synchronous Optical Network (SONET) and Synchronous Digital Hierarchy (SDH) to implement their systems. This results in long deployment cycles and large capital investment. Most WANs currently implement the 10Gb/s standard (OC-192) and the latest highest speed WANs are now being deployed using the 40Gb/s standard (OC-768). It is noteworthy that although the conventional wisdom is that 100GbE (Ethernet) will replace SONET/SDH as the WAN protocol somewhere in 2010/11, no SONET/SDH standard has yet been instituted for faster speeds.

Metropolitan Area Network Overview MANs generally span 100m to 400km and connect the “Long Haul” networks to more Local Access Networks. In effect they connect global networks (WAN) to smaller networks closer to the user (ISPs, LANs and SANs). MANs connect cities, corporate offices, data centers and storage networks. As a result of their lower cost, faster deployment cycles and greater local customer demand for Ethernet, MAN operators have been much quicker to migrate their network infrastructure to Ethernet Solutions than their WAN operator counterparts. As this continues, the general consensus here too is that 100GbE will soon replace SONET/SDH as the standard

Datacenter and Enterprise Network Overview In Very Short Reaches (VSR) below 100m (data centers, board-to-board, inter-rack, chip-to-chip and intra-chip interconnection), signals can easily be routed from fiber into copper and from optical to electrical interconnection. Due to easy installation and lower cost transceivers, copper provides a very cost effective solution. However, as previously noted, the demand for greater speed is expanding the use of the optical interconnection into such network domains.

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Figure 1 – Optical Network Universe as function of bit rate

  

Market Challenges and Opportunities Network traffic has been typically dominated by the triple-play of voice, video and data. Since the introduction of glass fiber in the 1970s, the speed rate of optical interconnected networks has grown from 155 Mb/s up to 10Gb/s-based systems. Today continued demand for greater bandwidth, largely driven by consumer internet video, digital television and enterprise backup applications, has significantly accelerated the optical interconnection bit rates to as high as 100Gb/s. The core network is expected to double every 2 years and in 2010 90% of data traffic is expected to be related only to video data.

This growth trend increases the need for system architects, transponder manufacturers and IC vendors to provide new cost effective solutions for higher bit rates (40Gb/s and 100Gb/s) across all links in the optical network universe. This presents several new challenges but also new opportunities for growth in markets with far greater volume than traditional fiber optic telecommunication.

High Speed Advanced Modulations In the submarine and terrestrial networks new 10Gb/s and 40Gb/s advanced modulation techniques have being solving most of the dispersion issues typical of such high speed transmission in very long distances. Fiber-transmission issues such as attenuation, chromatic and polarization mode dispersions, self and cross phase modulation are compensated by modulation schemes such as Forward Error Correction (FEC), Return To Zero (RZ) digital format, Duo-binary modulation, Differential Phase Shift Keying (DPSK), Differential Quaternary PSK (NRZ-DQPSK and RZ-DQPSK), with some time consequent more expensive semiconductor technologies and more complex transponders architectures. At 40Gb/s such advanced modulation schemes are applied in metro and regional application as well using channels already installed and conceived for 10Gb/s.

Optical Module Integration In the 10Gb/s segment, Multisource Agreements (MSAs) have being defining the standards for transponder modules, in order to guarantee interchangeability of components from different vendors. The increased level of integration is forcing the need to mount multiple pluggable parallel modules on the same rack with consequent need of smaller form factors, lower power consumption and very low cost, moving multiplexing/demultiplexing, clock data recovery and any necessary equalization from inside the module out into the host board. Transponder modules evolved from traditional 300pins, with size of 127x127mm2 and power consumption in the range of 10W down to XEMPAK, XPAK, X2 and XFP with sizes from 120x36mm2 to 78x18mm2 and power consumptions from 3W to 1.5W, to finally get to Small Factor Pluggable format (SFP) of 56.5x13.4mm2 size and a power dissipated of 1W or lower.

Even though most of the available market solutions are with discrete electronics devices with marginal power consumption and additional assembly costs, 10Gb/s SFP (SFP+) modules requirements find natural implementation into single silicon ICs transceivers with integrated transmitter laser driver, receiver post amplifier and digital control interface, emulating paths followed in wireless applications. By 2012

Inverted Return To Zero (IRZ) Duo-Binary

Figure 2 – Different 10G Eye Diagram Modulation Formats

  

shipments for 15M SFP+ modules are expected, corresponding to almost 50% of the entire 10GigE modules market [Ref.2].

40 Gb/s Very Short Reach Market 40 Gb/s market is finally becoming a reality and real networks have been in production for quite some time now. However system cost reduction and improved performance still remains a big challenge. Most of 40Gb/s transponders still make use of large electronics components in GPPO-connector based modules and very expensive cables with related phase adjustment issues in case of differential configurations. IC driver technologies still struggle to provide cost effective integrated surface mounted (SMD) solutions. Availability of high speed surface mounted packaged devices compatible with stringent Telcordia standard requirements and new reliable modulators technologies with low voltage drive (e.g. polymer-based EO modulators) can be the key enabler for cost effective integration of 40 Gb/s transponders and fast growth of such market.

Parallel Technology and Consumer Market Challenge In short and medium reaches, parallel technology (multiplexing or coupling into fiber parallel channels at specific bit rate) is coming back into the picture as the most attractive way to increase high speed rate at low cost, leveraging lower speed legacy platforms. Several options for 100Gb/s are under assessment by industry study groups [Ref.3] for standard definitions, such as 10x10GB/s, 5X20Gb/s and 4x25Gb/s. Some of the major challenges for such implementations, at transponder level, rely on legacy with existing systems and right technology for the optical laser with impact on laser driver feasibility. 100Gb/s parallel respect to 40Gb/s serial offers several advantages such as the use of lower cost ICs semiconductors with higher level of on-chip functionalities and easier packaging technology. VCSEL (Vertical Surface Emitting Lasers) based parallel technology has also finally come out of the traditional

X4 Drivers

VCSELs Opt. Detect.

X4 TIAs

Figure 4 – Parallel 4x3.125Gb/s Electro-optical Transceiverusing Gigoptix Parallel VCELs laser driver and TIA

Fig. 3 – Transponder MSA Evolution

300pins Module SFP+

  

niche markets such as Infiniband and Supercomputing, with 12x2.5Gb/s bit rates, moving into new very short reaches applications at 4x10Gb/s and 12x10Gb/s, in conjunction with the gradual replacement of traditional copper with optical interconnection. In fact, the performance limitation of copper, as the data rate increases, and the recent technical improvement in the area of VCSEL lasers, single/multi mode fiber, active cables and optical waveguides, make the optical parallel interconnection the most cost effective high performance solution for new generations of very short reach networks.

The advantages of the optical interconnection versus copper at 10Gb/s and higher speed are multiple [Ref.4], going from ultra large bandwidth (potentially up to 10Tz), small frequency dependent attenuation, immunity to Electromagnetic Interference (EMI), small size and scalability with future increase of speed through transmission of multiple wavelengths into a single channel (WDM). New applications and requirements for more speed and more efficient data management in the consumer markets, such as High-Definition Multimedia Interface (HDMI) for high definition television, home theater, information displays and cell phones as well, are accelerating the development of very low cost optical interconnect technology.

Fig.5 – Optical Interconnections Consumer Applications

Detector+ TIAs

VCSELs+ Drivers

  

GigOptix Technology for electro-optical interface This “natural” evolution towards larger bandwidth in particular at 40 and 100Gb/s, presents several challenges for both optical component manufactures and Integrated Circuits (IC) vendors. In fact, besides performance challenges, such new systems will need to demonstrate cost convenience with respect to previous lower bit rate systems ($/bit) and be compatible with Multisource Agreements requirements, once finalized. For example, 40Gb/s transponders will need to cost around 2.5 times the cost of today 10Gb/s counterpart to trigger mass adoption. At IC level, to overcome all the challenges that high speed transmission systems present, the convergence of different kind of technical skills and technologies need to happen. Millimeter-wave design techniques on IIIV technology, typical of wireless communications, highly integrated solutions with multiple digital functionalities and interfaces, typical of lower frequency Silicon technology, and high performance packaging, need to converge into single product solution for customers. GigOptix today combines the high speed, high performance expertise of previous iTerra Communication, leading the ultra-long and long haul IC drivers markets, with Helix Semiconductor longstanding experience in silicon parallel technology. This marriage blends together more than 10 years of proven product developments for optical transmitter and receiver, high voltage ultra broadband design techniques in IIIV technology and highly integrated parallel transmitter-receiver Silicon chip design capabilities. GigOptix, being fab-less, is able to combine his internal expertise with the right technology enabling the rapid growth of 40Gb/s and 100Gb/s future systems. Today, GigOptix offers a portfolio of high-speed physical media dependent (PMD) ICs interfacing any optical interconnection at both transmitter and receiver side, from ultra long reach down to very short reach, covering data rates from 10Gb/s to 40Gb/s and above. Such extensive range of reaches and data rates presents several challenges from both design expertise standpoint and use of proper semiconductor technology. Figure 6 represents the overall “world” in which GigOptix extends its technology.

The core component of an optical transponder is the optical laser or modulator at the transmitter side and the optical detector at the receiver side. Depending on the reach involved, different modulators and/or

10 to 100Gb/s

Figure 6 – Gigoptix Domain

  

detector technologies need to be used and proper modulator/laser driver and trans-impedance amplifiers (TIA) ICs need to be provided. Optical Modulators and Laser IC Driver Technology

Optical Modulators and Laser Diodes Technology In the transmission side, two different categories of optical modulators are used, based respectively on “direct modulation” and “external modulation” schemes. In Ultra Long Haul, Long Haul and Medium reaches only external modulators are used, since they overcome limiting factors of the direct modulation scheme related to interaction between laser frequency chirp and fiber dispersion, unacceptable in case of medium and long ranges. For reaches from 100km and above, LiNb Mach-Zehnder (MZ) external modulators type are typically used, requiring a high RF driving voltage (Vπ) from 10Vpp to 6Vpp depending on the adopted modulation technique. Mach Zehnder modulators are high performance modulators with large form factor, not suitable for optical integration. New generations of Mach-Zehnder modulator InP-based with integrated tunable lasers with input drive as low as 3 to 3.5Vpp (Low Vπ) are now available, with beneficial effects on transponder power consumption and semiconductor cost. In the Metro applications, for reaches from 40km and above, Electro-Absorption (EA) modulators are typically used. This kind of modulator, like the MZ modulator, is voltage controlled and absorbs the lasing wavelength when the applied RF voltage generates a shift of the semiconductor band-gap. EA modulators can require voltage drive as low as 2.3 to 3Vpp with very small form factor allowing higher level of integration. Below 40km, direct modulation finds is sweet spot since the length of the reach at this point allows the limitations due to the frequency chirp typical of this type of light sources to be neglected. Laser Diodes (LD) can be realized as Fabry-Perot (FB) and/or Distributed Feedback (DFB). These laser diodes are modulated by current and they need typically a modulation current from 50 to 80mApp with 25ohm termination, corresponding to a voltage swing from 1.5Vpp to 2Vpp. For very short reaches in the range of 1km down to 1m and below, Vertical Surface Emitting Lasers (VCSELs) dominate the optical interconnection due to the extremely low cost and the very low form factor allowing very high level of optical integration and parallelization. Laser modulation currents in this case are very low with values from 5mApp up to 12mApp.

High Speed ICs Drivers Semiconductor Technology In order to provide ICs able to drive various optical modulators and lasers, for different reaches and type of modulation, different semiconductor platforms and design skills need to be considered. Matching with different kind of modulators; flat group delay response, very small jitter degradation, external choke effects, stability over temperature, automated power control, two wires digital interface, these are typical challenges and requirements that IC driver designers need to face. However, the right choice of semiconductor technology is extremely important. The external modulators which need large voltage drive, require drivers IC fabricated with semiconductor technologies with high voltage breakdown and high cut off frequency. IIIV technologies such as InGaP or InP Heterostructure Bipolar Transistors (HBT) and GaAs p/HEMT devices, combined sometime with travelling wave design techniques, offer such properties. InGaP HBT is a proven reliable technology largely used in large volume wireless application and has several attractive characteristics suitable for high speed drivers up to 10Gb/s, like very larger breakdown, high cut off frequency, high linearity, simple material growth and temperature stability, low cost lithography and production.

  

GaAs pHEMT in 0.15um e-beam process is a technology extensively used in microwave and mm-wave application for radio links and it is very suitable for very large voltage designs due to gate-to-drain voltage breakdowns as high as 11V. p/HEMT cut off frequencies between 90 and 100GHz, combined with distributed amplified technology, are enough to achieve excellent 40Gb/s eye diagram performance. InP HBT has the highest Ft among the IIIV available technologies and the uses of double active channels (DHBT) allow reasonable breakdown voltages. IIIV processes have typically non recurrent development costs lower than Silicon but higher production cost for large volumes and today, with the exception of the fragile InP, are available in 6 inches wafer. However, IIIV technologies suffer for lack of high level integration capabilities and more process instability respect to Silicon. Several IIIV foundries are now investing effort and capital to integrate both HBT and pHEMT devices into the same GaAs substrate, mainly driven by large volume opportunities offered by wireless applications and the need for integration of high performance VCO with power amplifiers. The low modulation current lasers like LD and VCSEL require instead lower breakdown voltage driver IC technology, but higher level of integrated digital or analog control functions and lower cost solutions. SiGe

HBT BiCMOS provides an excellent platform in such case. SiGe HBT BiCMOS technology [Ref.5] by means of selectively implanted collector doping technique (SIC) allow the possibility of integrating on the same 8 inch silicon wafer, various SiGe HBT devices with different cut off frequencies (from 40 GHz up to 200GHz) and voltage breakdowns, and low bias supply CMOS transistors; This offers great design flexibility, versatility, fully integrated cost effective solutions, in some cases evolving into complete transceiver on chip. SiGe

HBT and CMOS technology have being continuously scaling down its geometry reaching today cut off frequency as high as 300GHz and gate lengths small as 45nm respectively. As previously mentioned, optical modulators can be used with advanced modulation techniques requiring additional high speed functions such as digital encoders, high precision broadband phase delays and clock drivers with high level of signal integrity. In such cases both IIIV and SiGe HBT technologies are very good candidates depending on the required speed. Recent advances in Silicon photonics make the CMOS technology extremely attractive for large scale optical integration on silicon and intra-chip interconnection for consumer application.

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Fig. 7 ‐ IC Driver Technologies

  

GigOptix Optical Modulators and Lasers Drivers Adopting digital design techniques mixed with broadband microwave design capabilities, GigOptix has developed a family of high performance multi-chip packaged drivers in IIIV-based technology for ultra long haul applications and advanced modulation. All drivers provide complete solution to interface the

multiplexer with optical modulator. These multi-chip packages include functions such as high speed encoder, broadband phase delay adjustments, power detection with reference diode for over temperature stabilization, providing excellent design flexibility to the transponder designer. All products have integrated low frequency choke and are packaged in hermetic sealed environment. Examples of such high performance packaged devices are the iT6135 NRZ/RZ driver and the iT6139/38 chip set for DPSK modulation, reported in Figure 7 and 8. InGaP HBT and p/HEMT processes are adopted in relatively shorter reaches applications as well, where GigOptix is able to provide excellent signal integrity drivers satisfying all needs for both long haul and metro application. Some of these examples are: the iT6155 SMD packaged 10Gb/s driver for LiNb MZ modulator, with 6Vpp output and 1.1W power dissipation;

the new 10Gb/s Gx6151 Low Vp Driver in QFN package, with 7Vpp differential output, suitable for InP tunable lasers; and the new Gx6120 EA modulator driver, with 2.5Vpp output and 600mW power dissipation, in QFN package as well. Both Gx6120 and Gx6151 have on-chip temperature compensation and ESD protection.

Clock

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Fig. 8 ‐ iT6135 10G NRZ/RZ Encoder + Driver

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Fig. 9 ‐ iT6138 and iT6139 10G DPSK Chip Set

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Fig. 10 ‐ iT6155 10G NRZ Modulator Driver

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Gx6120, 2.5Vpp

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Fig. 11 ‐ Gigoptix 4x4 QFN Low Voltage Drivers

6Vpp NRZ Data

  

The low modulation current lasers like LD and VCSEL require instead lower breakdown voltage driver IC technology, with higher level of integrated digital or analog control functions. In these kind of drivers automated optical power and diode modulation current control, to stabilize laser performance shift over temperature and time, must be provided on chip. SiGe HBT BiCMOS provide an excellent platform in such a case. Figure 12 shows the block diagram of GigOptix 4Gb/s and 10Gb/s VSCEL driver HXT3101.

Receiver-Transmitter Parallel Technology There are several ways to transmit more data into a fiber optic link and increase the aggregate bandwidth: one can install more fibers, but this would be a very expensive approach, not to talk about the dramatic effort when it comes to upgrading and increasing speed; a better method, is based on transmitting the signal in different time slots (Time Division Multiplexing) or allocate signals over different bandwidth slots, maintaining low channel-to-channel interferences, as used in wireless applications (Wavelength Division Multiplexing). At transmitter and receiver level there are three, or “two plus one”, possible approaches, 1) enlarge the bandwidth of the electronics performance, with several challenges related to technology limitations and cost, 2) parallelize multiple channels at much lower speed and multiplex them or coupled them into the fiber, 3) the combination of both previous approaches. Both first two approaches have being used in telecom and datacom in the last years, depending on link distances, related fiber dispersion issues, optical modulator/laser technologies and compatibility with previous existing systems. One of the factors that, in the recent years, boosted the development of parallel transmitter and receivers is definitely the technological improvements of VCSELs [Ref.6], allowing high speed transmission into low cost 850nm multimode fibers, opening incredible opportunities in datacom and consumer application.

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Figure 12 – HXT3101 10G VCSEL Driver Block Diagram

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Pictures Courtesy Avalon Photonics

Figure 13 – VCSELs array

  

These are some of the main features that make VCSEL very attractive for parallel transmission in very short links: 1) Planar technology and possible wafer-level testing (as opposed to cleaving for edge-emitters); 2) Funnel-like coupling (symmetrical) optical emission into multi-mode fiber; 3) Low threshold currents and low temperature dependency.

Further improvements of VCSELs technology are directed towards a frequency bandwidth increase up to 20 GHz, doubling his present aggregate bandwidth capacity and the extension of applicability from 850nm to 1310 and 1550 nm wavelengths as well. GigOptix, through the merge with Helix Semiconductor, extends its capabilities to Optical Receiver Transmitter Array (ORTA) Silicon-based VCSEL driver and TIA array design, positioning itself as the only IC semiconductor vendor with product portfolio from serial high speed, high voltage products to low power consumption and large aggregate bandwidth parallel transmitter-receiver chip sets. The Helix team is proud of being a pioneer in parallel technology development since the time of very first parallel optical systems (PAROLI).

HXT3404/HXR3404, HXT3412/HXR3412 and HXT4104/HXR4104 are examples of VCSEL driver arrays/TIA arrays chip set with speed rate of 4x3.125Gb/s, 12x4.25Gb/s and 4x10Gb/s. SiGE HBT BiCMOS technology and longstanding parallel transmitter/receiver design experience allow GigOptix-Helix design team to overcome challenges related to crosstalk, power dissipation, minimization of off-chip components, I/O channel-to-channel pitch, high level of integration and digital control functionalities. VCSEL Driver arrays are designed with features such as drive control functions per channel setting of average and modulation current, on chip input AC coupling capacitors with no need for external decoupling components, integrated thermal sensor, 100mw/channel typical power consumption at 8mA modulation current and 2 wires digital interface (2IC). TIA arrays are designed with limiter function, with programmable large output swing, per channel signal detect and signal strength indicator and CML compatible outputs. Output swing pre-emphasis is also provided to support high data rate operation. Both transmitter and receiver chips are fully programmable devices, offering great flexibility, with a minimal number of extra off-chip components. All designs are modular and scalable in number of channels allowing easy aggregate bandwidth increase as required. Applications for parallel transmitter-receivers chip sets are multiple: Supercomputing, where the increasing complexity of computation required by scientific and technological progresses have been encouraging large scale computer projects [Ref.4] to reach computational speed of 10 PFLOPS (105

floating-points number of operation/second) by 2010; Infiniband, for storage application; 10GBASE-LX4 for 10Gigabit Ethernet; Digital Video Interface (DVI) and High Definition Multimedia Interface (HDMI),

VCSELArray

Driver Array

TIA/LIA Array

PD Array

Fig. 14 ‐ Optical Receiver‐Transmitter Array

Fig. 15 ‐12x4.25Gb/s VCSEL Driver Array

  

which face the limitation of copper interconnection while requiring more Mpixels/second; Active cables, with a broad range of market applications.

Optical DVI Block Diagram SNAP12 SMA Block Diagram

Fig. 16 – Examples of parallel 4 and 12 channels

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Figure 16a : HXT4101, 4x10Gb/s VCSEL Driver

Figure 16b –4x10Gb/s Driver + VCSEL array 

  

GigOptix Roadmap and Vision GigOptix expertise covers from very high performance and ultra broadband design techniques in IIIV technology to highly integrated silicon chip design, with +10 years of proven product developments in both serial and parallel technology at transmitter and receiver. Today’s GigOptix IC portfolio is extremely focused on optically interconnection systems, extending from ultra long haul down to very short reach, allowing connections from continent to continent down to board to board and video interface, covering the entire telecom and datacom optical transceiver and active cable markets and consumer connectivity.

Being fab-less, GigOptix is able to choose the right technology for each application in cost effective way and provide to the customer the most appropriate solution. In particular, Figure 17 reports the present GigOptix portfolio and the area of new developments and expansion for 2008 and 2009. As it can be noticed in the two dimensional diagram, GigOptix is committed to provide market solutions in the areas such as:

1) 10G High Performance TIAs The need to improve system dynamic range with high signal over noise ratio in linear

mode, supporting Electronic Dispersion Compensation based optical links and long haul to ultra long haul transponders.

2) Compact and cost effective solution for 40Gb/s TOSA and ROSA and advanced modulations like DPSK and DQPSK

Single chip solution or integrated in small package form factor at costs competitive with present 10Gb/s transponders (x2.5 time of 10Gb/s cost).

3) 4x10Gb/s and 12x10Gb/s Receiver-Transmitter chip set for datacom, active cables and consumer markets.

ParallelRx

ParallelTx VCSEL Limiting

Amp * AGC* EA EO

100G HXR3112 HXT3112

40G HXR3412HXR3104

HXT3412HXT3104HXR4104

iT3042

10G HXR3404 HXT3404 HXT3101

iT3010iT3011iT3012iT3018

Gx6121iT4036

iT6139iT6138iT6135iT6134iT6155Gx6151

<10G HXR1101*HXR3401*

Legend : * includes TIA, Italic: under release

VSR 10cm-10m ULH < 1000KmReach

TelecomDatacom

Consumer

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Fig. 17 – Gigoptix Product Line

  

New generation of chip set with higher performance, higher yield and additional control features to simplify and reduce cost of transmitter and/or receiver integration.

4) 4x25Gb/s (100Gb/s) Receiver-Transmitter chip set for Telecom and Datacom Implement high speed design capabilities with high level of parallel integration and digital

control functionalities, offering easy assembly, low external high frequency expensive components, high end quality of eye diagram performance.

These 4 areas of focus are in line with the tridimensional world reported in the beginning of this paper and are clearly aligned with the trend of present and future data-communication world. The amount of data required by user’s, multiplies every year, and there is no doubt that ultra-broadband connections will enter soon in our homes, our TVs, computers and cellular phones. The advent of optical active cables and the use of optical interconnection in HDMI and USB3.0 is a confirmation of such a fast trend. However, which media will provide the

most effective solution for all the user’s needs is still a valid question..., mm-wave broadband wireless and optical network compete with each other but can be also complementary. Definitely, on board interconnection is a domain in which optical links, such as Silicon or Polymer [Ref.7] optical waveguides, are strong candidate solution to replace copper and solve most of the concerns regarding Electromagnetic Interferences (EMI) as well. This area has an enormous potential, just thinking about the development of new generation of cell phone becoming a high end portable multimedia center. Microprocessors will definitely increase their level of integration and speed and also at this level the copper will show its limitation opening the doors to Silicon photonics. In the last 10 meter user’s world, named also as Personal Area Network (PAN), covering most offices, medium sized conference rooms, and rooms in the home, both fiber connection and future 60 GHz wireless links are viable candidates [Ref.8]. Both optical fibers and mm-wave wireless PAN will be able to

interconnect various electronic devices, including laptops, PDAs, cameras, and monitors. Applications include wireless display, wireless docking station, and wireless streaming of data from one device to the other. ICs for both wireless optical interconnect and 60GHz transceivers, working at speeds of 20Gb/s and above, face similar challenges and can make use of same semiconductor technology platform. It is opinion of the author that the two worlds, optical and wireless will coexist and new IC

Video

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Fig. 18 – HDMI System

Gateway

Fig. 19 – Optical interconnection and 60 GHz wireless into future home

  

transceivers will need to be developed to interface various standards and protocols; optical fiber and 60 GHz links combined will be the ultra-broadband equivalent network provided today by copper and WiFi, with the advantages of better security, no interferences and naturally.. more and much faster data!

References Ref.1 “40Gb/s in metro and regional optical networking”, Dr. Klaus Grobe, ADVA Optical Networking

Ltd. Ref.2 “Optical Components Markets: 2007, Vol.1” CIR Report 2007 Ref.3 “IEEE 802.3 High Speed Study Group 100GbE Silicon Photonic Platform Considerations” Salah

Khodja, APIC’s Optoelectronics, IEEE 802.3 HSSG, Jan 17th 2007, Monterey, CA. Ref.4 “Technical Trends in Optical Interconnections Technology”, Kanji Takeuchi, Science and

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