FLECTRONIC DESIGIE
`
`TECHNOLOGY: APPLICATIONS: PRODUCTS «SOLUTIONS
`
`APENTON PUBLICATION $10.00
`DECEMBER 1, 1997
`
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`“MENS/DOCSIS MAC Clears PathForCable-Modem Invasion p. 69
`
`Titashl IEDM Conference Examines Leading-Edge Device Developments p. 39
`\
`At IEDM: Memory, Logic Power Devices, EDA, Sensors, And Displays p. 40
`h
`Line-Driver Design For Broadband Communications Applications p. 81
`4
`Parasitic Extraction Tools Aid DSM IC Designs p.97
`t
`Harness The Power Of The ACPI/Smart Battery Standard p. 113
`. Pick The Perfect Chassis To Ensure System Longevity p. 127
`
`
`
`MEDIATEKEX.1007
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`MEDIATEK EX. 1007
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`

`

`If you’re charged with designing low-power applications,
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`
`MEDIATEKEX.1007
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`
`ELECTRONIC DESIGN
`
`TECHNOLOGY: APPLICATIONS: PRODUCTS- SOLUTIONS
`
`December 1, 1997 Volume 45, Number 27
`
`
`EDITORIAL OVERVIEW
`
`
`
`¢C Clears Path For Cable-Modem Invasion 69
`
`
`
`@ Annual IEDM Conference Examines Leading-Edge Device Developments 39
`At IEDM: Memory, Logic Power Devices, EDA, Sensors, And Displays 40
`BB Line-Driver Design For Broadband Communications Applications 81
`
`
`Wi Parasitic Extraction Tools Aid DSM IC Designs 97
`
`
`i Harness The Power Of The ACPI/Smart-Battery Standard 113
`WH Pick The Perfect Chassis To Ensure System Longevity 127
`
`PSG CS
`
`50 IEDM Focuses On Advanced Device Models
`® Models offer new hope in tackling deep-
`submicron issues dealing with process
`accuracy and interconnect.
`
`1i
`
`] 1
`
`US
`
`
`
`
`
`39 Annual IEDM Conference Examines Leading-Edge
`
`Device Developments
`
`* Hear about the latest in memory and logic
`ICs, compound semiconductor devices,
`
`simulationtools, and sensors and displays.
`40 MemoryAnd Logic Structures Are Getting Faster
`
`And Denser
`* Designers detail advanced process techniques
`
`andfiner-dimensiondesign rules at IEDM to
`
`build next-generation memories and logic.
`
`A8 Rivalries BetweenSilicon And Exotic Semiconductors
`Abound At [EDM
`* SiGe and vanilla silicon move into RF and
`
`
`optical applications as compound semi-
`
`conductors stake outtheir niches.
`
`
`
`
`i 60 Sensors And Displays Highlighted At IEDM
`| © Advanced device structures and new
`i
`technologies are opening the doorfor emerging
`display and sensor-based applications.
`
`COMMUNICATIONS TECHNOLOGY
`69 MCNS/DOCSIS MAC Paves The Way For A
`Cable-Modem invasion
`* Thefirst standards-compliant chip Mqayyq'
`means affordable, interoperable, Sita
`cable modems, with speed and
`securityfeatures.
`
`1|t
`
`!
`
`
`published twice monthly except for 3
`ELECTRONIC DESIGN (ISSN 0013-4872) is
`
`Issues in May, 3 issues in August, 3 issues in
`ictober, and 3 issues in November by
`Sipattor Ave., Cleveland, OH 44114-25.
`43. Paid rates
`Penton Publishing Inc., 1100
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`393.0204.Printed in 0.
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`S.A.Title registered in U.S. Patent Office.
`
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`rights reserved. The contents of this
`Copyright 1997 by Penton Publishing Inc. All
`publication may not
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`the
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`218}
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`
`habelPa
`Editorial ...........«22
`* Tiny Engines Fuel A
`Revolution
`F
`
`© Consumer Electronics’
`Potential
`
`Technology
`
`Nonny merryset)
`Technology —
`fi
`Breakthrough ........33
`© 35-GHz0.5-WGaAs
`pHEMTpointsthe way
`toward low-cost volume
`production ofMOCVD
`MMICs
`-
`© 0.1-mm electrostatic
`microrelays switch atwp
`to 100 GHz
`* Development ofblue
`phosphor spawnsfull-
`colorEL displays
`
`:
`
`Info Page oheteten oo IO
`(how tofind us)
`
`Index of Advertisers .. 184
`
`Reader
`Service Card ....184A-D
`
`MEDIATEKEX.1007
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`
`
`MCNS/DOCSIS MAC Clears A Path For
`The Cable-Modem Invasion
`The First Standards-Compliant Chip Means Affordable, Interoperable,
`Cable Modems, With Speed And Security Features.
`Lee Goldberg
`|
`
`fa.» oflargecableinterestsformed
`dia cable networking |
`
`systems/Data-Over-Cable-Ser-
`the MCNSgroup. Comprised
`
`_ of heavyweightslike Comcast
`vice Interface Specification ¢
`eat
`
`'
`and Time-Warner, MCNS
`(MCNS/DOCSIS) compliant
`1) teamed with the cable indus-
`
`media-access controller (MAC) ©}
`i
`|
`try’s research consortium, Ca-
`chip, the cable data revolution
`
`
`e277: we
`has begun in earnest. By rolling —
`ble Labs, Louisville,
`
`
`out thefirst integrated imple-
`Colo., to produce
`
`their own open'standard for
`
`mentation ofthe cable industry's
`
`/
`, moving data between cable
`recently developed DOCSIS,
`
`network headends and sub-
`Broadcom Corporation has
`
`paved the wayfor the rapid de-
`™ scriber’s homes.
`
`| velopment ofinexpensive con- &
`
`Enter DOCSIS
`sumer-oriented cable data appli-
`jay
`
`* Thefirst fruit of this alliance is
`ances. This move could providea -
`
`the DOCSIS specification, de-
`critical jump-start for the
`
`
`emerging cable data industry. If esa
`». veloped by a group of manufac-
`
`the next year goes according to
`turers, underthe direction of
`
`
`plan, we mayseea device that
`MCNSand Cable Labs. Partic-
`
`
`saa gaane ao“na"S
`delivers multimegabit down-
`ipants in the initial develop-
`
`ment of DOCSIS included Gen-
`stream Internet access being
`
`sold at K-Marts andelectronic discount
`eral Instruments, LAN City (nowa
`
`stores at prices comparable to today’s
`part of Bay Networks), and Broadcom.
`This spec outlines the physical layer in-
`56-kbit POTS modems.
`terfaces, MAC andtransport proto-
`cols, security provisions, and other
`specifications necessaryfor designing
`interoperable cable data components.
`Subsequent fine-tuning was per-
`formed in an open forum hosted by Ca-
`ble Labs and attended by most major
`players in the cable industry. The re-
`sult is a standard that meets the needs
`ofcurrent users and anticipates the de-
`mandsof future applications.
`DOCSISis designed to employ one
`or more unused video channels within
`the 54-to-860-MHz cable broadcast
`
`cE POeSRUBCOUECCelCLC
`
`'1i!!11''1'1I1t''iL'''t11i1111111i111
`
`
`
`
`ith the introduction of
`
`W::BCM8220multime-
`
`|
`
`
`
`
`
`
`surfing began to erode cable’s near-
`lock on passiveleisure activities.
`After severalill-fated adventures
`with video-on-demand, interactive
`The Broadband Wars
`shopping, and other attempts to dic-
`The development of DOCSIS and
`tate consumertaste, cable marketeers
`the introduction of the BCM3220 mark
`stumbled over the obvioushot applica-
`
`| the first hopeful chapterin the trou-
`tion, broadband Internet access. Once
`
`} bled history of cable media’s efforts to
`early trials demonstrated the eco-
`
`maintain its dominantrole in captur-
`nomic potential, it became clear that
`
`ing the hearts, minds, and eyesof the
`the only wayto achievea critical mass
`
`American consumer. In the early
`of users was to develop a transmission
`
`nineties, the cable television industry
`standard that would enable the pro-
`
`faced a double threat: While saturated
`}
`duction of mass-produced, inexpen-
`
`subscriber markets yielded flattening
`sive, interoperable cable modems and
`
`set-top boxes (Fig. 1).
`revenues, satellite television, sophisti-
`
`
`cated computer games, and Internet Frustrated by the slow progress of
`
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`standards committee, a group
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`
`MEDIATEKEX.1007
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`

`

`
`
`iF
`header i oe|TT
`
`BCM3116
`or
`BCM3118
`
`interface
`
`Control
`
`MAC
`
`processing
`
`,
`
`Timing
`recovery
`circuit (TRC)
`
`[tayare
`
`Dual-port
`
`saan | controller
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`|
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`infomation
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`i}re|pr
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`
`2. The BCM3220 MACchip incorporatesall control, stream-processing, and security functions required for a
`MCNS/DOCSIS-compliant cable modem. A memory-based DMA interface assuresefficient data transfers to
`and from the host controller. Both baseline and high-security modes also are supported.
`
`businesses which need them.
`
`MPEG Everywhere
`Oneinteresting aspect of DOCSIS
`is that it uses MPEG ITI transport
`streams to move IP data. While not es-
`sential for today’s applications, the
`standard’s developers were looking
`toward the future. Today, MPEG en-
`capsulation provides DOCSIS witha
`reliable, well-defined methodof set-
`ting up multiple channels within a sin-
`gle data stream. In the near future,
`MPEGencapsulationwill allow a sin-
`gle cable modem to support multiple
`sessions and multiple users, as well as
`delay-sensitive multimedia streams
`for voice or video over IP.
`Using MPEGII transport streams
`also will allow DOCSISto interoperate
`with the Open Cable standard for digi-
`tal cable television thatis currently un-
`der development. Open Cable also em-
`ploys MPEGIItransport streamsfor
`all of its media flows. This feature
`should greatly simplify traffic switch-
`ing and processing within tomorrow's
`cable networks
`Althoughit has some similarities to
`the carrier-sense multiple-access/colli-
`sion-deteet (CSMA/CD)protocol em-
`
`1ti11tiI11111Iiii41‘i'11i1i11ii1i1114'1'||'1'4'1'11't''I111111i1111i
`
`feature allowsit to accommodate both
`traditional connectionless Internet
`traffic, as well as latency-sensitive
`multimedia streams. Selectable QoS
`also will let cable companiesoffer
`tiered services with various guaran-
`teed bit rates and levels of latency to
`
`11'''1'111'1I
`
`BCM3037
`upstream
`OPSK/16-OAM
`modulator
`
`Microcontroller
`with Ethernel MAC
`
`BCM3116
`QAM receiver
`
`10Base-T
`:
`transceiver
`
`1. ADOCSIS-compliant cable modem receivesits data over unused 6-MHz video channels within
`the normal cable spectrum. Upstream traffic is carried back to the system headend in the 5-to-
`45-MHz sub-split band. To ensure that the modem will operate properly and notinterfere with
`other units, both the downstream receiver and upstream modulator/transmitter operate under
`the control of the BCM3220, or other DOCSIS-compatible MAC.
`
`
`
`MEDIATEKEX.1007
`Page 5 of 8
`
`
`
`ZIANVAKVS-BASEV CABLE*MVVUEM MAY |
`
`
`
`
`
`
`
`2Memoryinterface~~
`
`spectrum to transmit IP-based
`data across hybrid fiber coax-
`ial
`networks. Complex
`phase/amplitude modulation
`enables each 6-MHz down-
`stream channelto bring data
`into subscribers’ homes at up
`to 38 Mbits/s. Depending on
`the bit rate selected by the op-
`erator, the shared downstream
`channel uses either 64- or 256-
`point quadrature-amplitude
`modulation (QAM). Whilelittle
`is known about what actual
`bandwidth requirementswill
`be,initial results from field tri-
`als suggests that a single chan-
`nel will provide groups of 200
`to 1000 subseribers with Inter-
`net. access that is substantially
`faster than today’s best POTS-
`based services.
`For communication from the
`home to headend, DOCSIS
`uses the 5-to-40-Hz sub-split
`band as a return path. Using
`QPSKtoday, or 16-QAMin sub-
`sequentversions, the upstream
`channelhas a theoretical maxi-
`mum throughput of 10 Mbits/s
`(see “Broadband To The Home: Chal-
`lenges On the Last Mile,” Electronic
`Design, Oct. 2, 1995, pp 67-83).
`Since DOCSIS alsois intended to
`support IP-based video, provisions
`have been madeto support several
`levels of quality of service (QoS). This
`
`block (MIB)
`with FEC
`
`MEDIATEK EX. 1007
`Page 5 of 8
`
`

`

`te)esse)es COMMUNICATIONS TECHNOLOGY STANDARDS-BASED CABLE-MODEM MAC|
`
`ecurity for the DOCSIS
`cable modem system is
`divided between an
`elaborate Full-Security
`Specification with remov-
`able, renewable security
`modules, and a low-cost, sim-
`pler schemecalled Baseline
`Privacy (BPD). BPIis based
`on full-bodied concepts,be-
`ginning with the 56-bit Digi-
`tal Eneryption Standard
`(DES)Cipher Block Chain-
`ing algorithm, yet unbur-
`dened by someof the more
`costly and complex security
`features of its heavy twin.
`All DOCSIS cable modems
`are required to support BPI,
`ensuring that basic data pri-
`traffic originating from or destined toa particular modem to
`vacy is maintained in the shared cable environment.
`identify a Traffic Eneryption Key (TEK)to use. Each TEK.
`Privacy is more than sufficient for Internet access appli-
`isa pair ofeven and odd 56-bit keys. Hach key also has a cor-
`cations because it makes a number ofassumptions on the ap-
`responding 56-bit initialization vector.
`plication it serves, namely that Internet access is two way,
`and therefore not susceptible to passive theft ofservice; that
`All DOCSISframes have headerfields that are never
`encrypted and include an optional field called an Extended
`it’s not particularly valuable to anyone, but the user; that re-
`Header. Mainly for protocol expansion, this variable area in
`ally important transactions over the Internet (like banking)
`the DOCSISheader is used to contain the Baseline Privacy
`will be secured with end to end application layer security;
`Extended Header(see thefigure). The SID is contained in
`and that by changing keysoften,individual keys are not
`worth the trouble ofstealing.It also is much easier to detect
`the BPI Extended Headerfor each frame to identify which
`TEK to use,
`clones and unauthorized users of cable modems because the
`Each DOCSISframe that will be encrypted must contain
`service is two-way. The modem systemis unlike broadcast
`a Privacy Extended Header. The header contains atype
`pay-per-view video that can be hacked in private—clone
`and version field as well as the SID identifying a particular
`modems must not only listen, but speak to be useful.
`encrypted data flow, The SID field also contains an en-
`DES is a cryptographic algorithm that takes binary
`able/disable bit that controls encryption for that particular
`coded data and applies a knownalgorithm using a ran-
`frame and a togglebit. The togglebit is used to signify the
`domly generated 56-bit key to produce unintelligible or en-
`current epoch; that is whetherthe even or odd keyis in use
`erypted bits, The algorithm can be known by manybut the
`data will be unintelligible unless the keyis shared by both
`for this frame. This toggle bit allows the protocolto set up a
`new TEKin the even key slot while actively using the odd
`parties. This mutually shared secretallows encrypted traf-
`key, When thefirst frame to use the new keyis received,the
`fic to remain private to those who havethe keys. A 56-bit
`toggle bit indicates that the epoch has changed and that the
`key has 70 quadrillion possible values, and the only guaran-
`other key is nowin use. The togglebit also is the least-sig-
`teed way of discovering a truly random keyis to try all of
`nificant bit of the 4-bit sequence field that is used to track
`them. Changing keys often reduces thelikelihood of suc-
`the history ofup to 16 keys by the key exchange protocol.
`cess even further. The challenge in this type of eryptogra-
`Baseline Privacy encrypts data in both up and down-
`phy is how to exchange the secret keys easily, yet securely.
`stream directionsof the cable plant using the extended
`Cipher Block Chaining is a form of DESthat increases
`headers to indicate what to do. DOCSIS MAC messagesal-
`the strength ofthe encryption byusing an initialization vec-
`low a simple key exchange protocol to operate between the
`tor sent down with the key to preset its encryption hard-
`headend(or cable modem termination system) and the ca-
`ware state. For each eight-byte block encrypted, instead of
`resetting or reinitializing, the circuit retains the result from
`ble modems. Keys are updated frequently and the registra-
`the previousblock’s encryption. This chainingof results
`tion databases are watched vigilantly for clones. This pro-
`vides subscribers with a low-cost but vey effective “lite”
`from one block to the start; ofthe next makes the cryptogra-
`phy strongersince a hacker would need to reconstruct the
`securitysolution for ensuring data privacy.
`Contributed by Thomas J. Quigley, director ofthe Resi-
`entire sequenceto break the code instead ofjust one block.
`Baseline Privacy uses a Service ID (SID) associated with
`dential Broadband Business Unit at Broadcom Corp.
`
`
`
`
`
`MAC_PARM
`
`LEN
`
`Extended header
`
`lilaeca
`
`
`
`=4
`
`MEDIATEKEX. 1007
`Page 6 of 8
`
`|1
`
`1I1'1It1tItI1111I'''tIi1't111It'''11111114i4411
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`i1't'I11t'II''U111ti'41111111'
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`DOCSIS oe eeeee
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`
`Request
`
`BP EH
`element
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`Other EH elements
`
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`
`
`Naas
`
`MEDIATEK EX. 1007
`Page 6 of 8
`
`

`

`Le VaEien STANDARDS-BASED CABLE-MODEM MAC
`
`Pl
`
`seription (UCD) messagesare usedto |
`tell the subscriber equipment what|
`the headendis expecting to see.
`
`SPI On Board
`Part of the BCM3220’'s jobis to jn.|
`terpret these messages and set the
`transmitter’s modulation, timing, and
`FEC parametersaccordingly. With |)
`this in mind, the MACchip sports an |
`industry-standard serial program-
`ming interface (SPT) bus masterinter. |
`face which can be used to configure
`and control both the QAM receiver |
`and Burst modulator chips onthefly,
`If SPI-capable components are used
`elsewhere in the modem’sdesign,the
`BCM3220 also can be programmed to
`set their operating values, such as
`tuner frequencies and amplifier gains,
`The chip’s upstreamprocessing sec-
`tion is responsible for passing data to
`the headend. Interfacing directly to
`the BCM3037 QAM/QPSK modulator,
`it transmits MPEG-encapsulated data
`within a series of time slots that it
`shares with the other modemsin the
`network. To accomplish this task
`smoothly, it places requests to the
`headend during specially designated
`time periods.
`The BCM3220 MAC keepsthese
`time periods straight by referring to
`the upstrearn bandwidth availability
`map that the headend routinely broad-
`casts. Stored in on-chip registers, this
`maptells the modem whenit can re-
`quest an upstream timeslot, transmit
`its data, or perform network mainte-
`nance and managementfunctions. For
`extended data transfers involving
`more than one block of data, the
`BCM3220 automatically requests a se-
`ries of prescheduled piggyback time
`slots. This technique allows it to use a
`single transfer request to move multi-
`blockfiles, increasing throughput and
`reducing access latency.
`
`Pretty Darn Good Privacy
`Of course, wheneveryou're using a |
`broadcast media to transmit sensitive |
`data, the issue of security always
`comesup. According to Tom Quigley,
`product manager at Broadeom, DOC-
`SIS provides two grades of security at
`the hardwarelevel. Both employ the
`date encryption standard (DES)algo-
`rithm and Rivest, Shamir, and Adel-
`man (RSA) key exchange. The real
`difference between the baseline and
`
`MEDIATEKEX. 1007
`Page 7 of 8
`
`crypt logic and a DMA-based, shared-
`RAMhostinterface that has been op-
`timized for Motorola’s QUICCseries
`of 680xx and PowerPC-based con-
`trollers. To insure fast, efficient trans-
`fers, incoming and outgoing Ethernet
`packets are exchanged whole-cloth in
`a single operation, with no buffer
`copying or other overhead-intensive
`intermediate steps.
`The downstream section of the
`BCM8220 interfacesdirectly with the
`BCM3116 QAMreceiver. Since DOC-
`SIS requires that data be encapsu-
`lated within MPEG II transport
`streams, the MACis responsible for
`extracting it before passing IP frames
`to the host system. Broadcom’s de-
`signers went the spec one better and
`included an MPEG II filter portin
`
`
`ORSACMeea
`
`MMC
`Layers OfSecurity Are
`BONAL Lee
`
`
`
`
`
`
`
`a“
`
`Tunneling” Protocol.
`
`their device. This feature allows the
`BCM8220 to be programmed to pass
`through selected MPEG video
`streams to an external decode
`circuit— a handy feature when de-
`signing
`a
`combination
`cable
`madem/set-top box.
`In addition to recovering and pro-
`cessing data, the downstream proces-
`sor must perform decryption func-
`tions and receive synchronization and
`control messages from the headend.
`These messages enable the headend to
`tell the modem to adjust its data rates
`and other parameters to match chang-
`ing line conditions.
`To avoid conflicts in a shared-media
`environment, the MACuses several
`tools to keep the modem synchronized
`with its neighbors and headend.First,
`the time-base recovery (TRC)func-
`tion detects and interprets broadcast
`timing information. Since MCNS
`modemscan be programmedfor a va-
`riety of data rates and transmission
`parameters, upstream channel de-
`
`ployed by most other 802-flavored me-
`dia, DOCSIS employsa time-slotted
`noncontention access scheme for most
`of its communication. In order to main-
`tain order on a busy cable, the MAC
`chip in each subscriber’s modem must
`keep track of network timing, as well
`as its place in the overall communica-
`tions flow. In contrast to Ethernet’s
`CSMA/CDprotocol, this more orderly
`access schemeallows cable operators
`to fill their pipelines at up to 75% of
`their theoretical capacity. This factor
`is critical when subscribers are shar-
`ing bandwidth with 200+ neighbors.
`To satisfy even the terminally para-
`noid, two layers of security are pro-
`vided within DOCSIS,plus the poten-
`tial
`for a completely shielded
`“tunneling” protocolfor sensitive data
`transfers such as personal records or
`credit card numbers.
`If DOCSIS seemsa bit complicated,
`it’s becauseit really is. The standard’s
`rich feature set and traffic control
`scheme require approximately
`100,000 gates (plus RAM) to imple-
`ment, yielding an effective processing
`powerof 30 to 40 MIPS.In practice,
`you'd probably need a muchfaster|
`CPU to makesure it was available for
`all the demandingreal-time opera-
`tions. Despite the complexity, Broad-
`com was able to follow the evolution of
`the standard anddeliver a product
`within nine monthsofits finalization,
`thanksto its close participation in the
`development committee.
`Anotherfactor that gave Broadcom
`an inside edge on delivering the MAC
`chip is its proprietary silicon compiler
`technology. Their specially developed
`software can translate algorithmsdi-
`rectly to gate layouts optimized for
`minimal cross-talk, propagation delay,
`and other critical parameters. While it
`is primarily used to implementblind-
`ingly fast digitalfiltering and correlat-
`ing algorithms in CMOSlogic arrays,
`the same software also has been em-
`ployed to lay out Fast Ethernet MACs
`and other controllogic requiring com-
`plex signal paths andtight timing.
`
`
`
`sate)syeae
`
`aleso
`
`A Peek Inside
`Examining the block diagram of the
`BCM3220 reveals the basic functions
`required to support full-duplex com-
`munication using the MCNSprotocol
`(Fig. 2). Many complex functions have
`been implemented plus encrypt/de-
`
`' i ' ' 1| ' ‘ , ’ : ;11ii
`
`i1
`
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`
`MEDIATEK EX. 1007
`Page 7 of 8
`
`

`

`full security is the use of a highlyge.
`cure, removable hardwarekeyfop
`sensitive applications. In addition,fuy
`security uses the full authenticatiog
`protocol and a 1024-bit key to encrypt
`the exchange oftraffic keys.
`The BCM38220 supports both levelg
`of security. It performs the DESelee.
`tronic-code-book (ECB) and cipher
`block-chaining (CBC) functionsip
`hardware, along with residual block
`termination (RBT). Normally, a 56-bit
`key is employed, although it can be
`programmed to run withacrippled 40-
`bit key for export applications.If de.
`sired, the MACchipalsolets design-
`ers include application-based security
`measuresfor a third layer of end-to.
`end protection (see “DOCSIS Secu.
`rity: Baseline Privacy,” p. 74).
`The advent of the DOCSIS stan-
`dard may proveto be a crucial turning
`point in the broadband wars between
`telephone and cable networks. While a
`shared-media system like cable will al-
`ways be a less than optimal way to de-
`liver data to homes, MCNS has donea
`very good job in making cable media
`as efficient, reliable, and secure as pos-
`sible. For more information, contact
`the MCNS groupat: Cable Labs, 400
`Centennial Parkway, Louisville, CO
`80027; phone (803) 661-9100;fax (303)
`661-9199.
`
`Excess inventory today...student opportunity tomorrow TL MAC|
`
`
`
`
`Turn your excess inventory into a
`substantial tax break and help
`send needy kids to college as well.
`
`Call for your free guide to learn how
`donating your slow moving inventory can
`mean a generous tax write off for your company.
`
`Executive Director
`
`P.O. Box 3021, Glen Ellyn, IL 60138
`FAX (708) 690-0565
`
`Rambo’s Uzi
`Broadcom’sfirst silicon implemen-
`tation of the DOCSIS standard will
`surely giverise to a first generation of
`low-cost, interoperable cable modems.
`Teleco and xDSL advocates should not
`take this newslightly. Given the ag-
`gressive nature ofthe cable industry,
`providing them with a standards-conr |
`pliant MAC chiplike the BCM2220 will
`Call (708) 690-0010
`be like handing Ramboaloaded Uzi.
`Peter Roskam
`
`—|
`
`Price AND AVAILABILITY
`Available in sample quantities now, the
`BCM38220 will be in full production during
`thefirst quarter of 1998. Pricingfor the pare |
`is $30 each, in quantities of 10,000.
`_
`BroadcomCorp., 16251 Laguna Canyom
`Rd., Irvine, CA 92618; (714) 450-8700; fas
`(714) 450-8710; Internet: www.broadcom.com,
`CIRCLE 551
`
`
`How VALUABLE
`HIGHLY
`MODERATELY
`
`CIRCLE
`552
`
`SLIGHTLY
`
`MEDIATEKEX. 1007
`Page 8 of 8
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`MEDIATEK EX. 1007
`Page 8 of 8
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`