SFF Committee SFF-8461 Specifications for SFP+ Active

SFF Committee SFF-8461 Specifications for SFP+ Active
Development
*** THIS IS NOT A FINAL DRAFT ***
SFF-8461, Revision 0.1
SFF Committee documentation may be purchased in hard copy or electronic form.
SFF specifications are available at ftp://ftp.seagate.com/sff
SFF Committee
SFF-8461 Specifications for
SFP+ Active Cable Specifications and Alternate Test Methods
Revision 0.1
21st of August 2009
Secretariat: SFF Committee
Abstract: This specification defines SFP+ active cabling for SFF-8431 linear and limiting host. This specifications also defines
alternate cable test method based on S-parameters.
This specification provides a common reference for system manufacturers, system integrators, and suppliers. This is an internal working specification of the SFF Committee, an industry ad hoc group.
This specification is made available for public review, and written comments are solicited from readers. Comments received
by the members will be considered for inclusion in future revisions of this specification.
Support: This specification is supported by the identified member companies of the SFF Committee.
POINTS OF CONTACT:
Technical Editor:
Ali Ghiasi
Broadcom Corporation
3151 Zanker Road
San Jose, CA 95134
Voice: (408) 922-7423
EMail: aghiasi@broadcom.com
Chairman SFF Committee
I. Dal Allan
ENDL
14426 Black Walnut Court
Saratoga, CA 95070
Voice: (408) 867-6630
EMail: endlcom@acm.org
SSWG Leader:
Greg McSorley
Amphenol Corporation
Voice:
Email: greg.mcsorley@amphenol-gcs.com
SFP+ (Active Cable Specifications and Alternate Test Methods)
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The following member companies of the SFF Committee voted in favor of this industry specification:
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tbd
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The following member companies of the SFF Committee voted against this industry specification:
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tbd
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The following member companies of the SFF Committee voted to abstain on this industry specification:
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tbd
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The user's attention is called to the possibility that implementation to this Specification may require use of an invention cov- 13
ered by patent rights. By distribution of this specification, no position is taken with respect to the validity of a claim or claims
of any patent rights in connection therewith. Members of the SFF Committee which advise that a patent exists are required 14
to provide a statement of willingness to grant a license under these rights on reasonable and non-discriminatory terms and
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conditions to applicants desiring to obtain such a license.
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EXPRESSION OF SUPPORT BY MANUFACTURERS
SFP+ (Active Cable Specifications and Alternate Test Methods)
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The development work on this specification was done by the SFF Committee, an industry group. The membership of the
committee since its formation in August 1990 has included a mix of companies which are leaders across the industry.
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When 2 1/2” diameter disk drives were introduced, there was no commonality on external dimensions e.g. physical size,
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mounting locations, connector type, connector location, between vendors.
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The first use of these disk drives was in specific applications such as laptop portable computers and system integrators
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worked individually with vendors to develop the packaging. The result was wide diversity, and incompatibility.
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The problems faced by integrators, device suppliers, and component suppliers led to the formation of the SFF Committee as
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an industry ad hoc group to address the marketing and engineering considerations of the emerging new technology.
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During the development of the form factor definitions, other activities were suggested because participants in the SFF Committee faced more problems than the physical form factors of disk drives. In November 1992, the charter was expanded to 11
address any issues of general interest and concern to the storage industry. The SFF Committee became a forum for resolving
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industry issues that are either not addressed by the standards process or need an immediate solution.
13
Those companies which have agreed to support a specification are identified in the first pages of each SFF Specification.
Industry consensus is not an essential requirement to publish an SFF Specification because it is recognized that in an emerg- 14
ing product area, there is room for more than one approach. By making the documentation on competing proposals avail15
able, an integrator can examine the alternatives available and select the product that is felt to be most suitable.
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SFF Committee meetings are held during T10 weeks (see www.t10.org), and Specific Subject Working Groups are held at the
convenience of the participants. Material presented at SFF Committee meetings becomes public domain, and there are no 17
restrictions on the open mailing of material presented at committee meetings.
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Most of the specifications developed by the SFF Committee have either been incorporated into standards or adopted as
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standards by EIA (Electronic Industries Association), ANSI (American National Standards Institute) and IEC (International Elec20
trotechnical Commission).
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The SFF Committee activities support the requirements of the storage industry, and it is involved with several standards.
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If you are interested in participating or wish to follow the activities of the SFF Committee, the signup for membership and/or
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documentation can be found at:
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www.sffcommittee.com/ie/join.html
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The complete list of SFF Specifications which have been completed or are currently being worked on by the SFF Committee
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can be found at:
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ftp://ftp.seagate.com/sff/SFF-8000.TXT
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If you wish to know more about the SFF Committee, the principles which guide the activities can be found at:
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ftp://ftp.seagate.com/sff/SFF-8032.TXT
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Suggestions for improvement of this specification will be welcome. They should be sent to the SFF Committee, 14426 Black 31
Walnut Ct, Saratoga, CA 95070.
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Foreword
SFP+ (Active Cable Specifications and Alternate Test Methods)
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The following interface standards are relevant to SFP+ Specifications.
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SFF-8431 - Specifications for Enhanced Small Form Factor Pluggable Module SFP+
SFF-8432 - Improved Pluggable Formfactor (ftp://ftp.seagate.com/sff/)
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SFF-8083 - Improved 0.8mm Card Edge Connector (ftp://ftp.seagate.com/sff/)
SFF-8089 - SFP Rate and Application codes (ftp://ftp.seagate.com/sff/)
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SFF-8079 - SFP Rate and Application Selection (ftp://ftp.seagate.com/sff/)
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SFF-8472 - Diagnostic Monitoring Interface for Optical Transceivers (ftp://ftp.seagate.com/sff/)
INF-8074i - SFP (Small Form Factor) Transceiver (ftp://ftp.seagate.com/sff/)
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INF-8077i - 10 Gigabit Small Form Factor Pluggable Module (XFP MSA) (ftp://ftp.seagate.com/sff/)
FC-PI-4 - Fibre Channel - Physical Interface-4
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10GFC - Fibre Channel - 10 Gigabit
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FC-MJSQ - Methodologies for Jitter and Signal Quality Specifications FC INCITS Project 1316-DT Rev 14.1, June 5, 2005
IEEE 802.3 - IEEE Standard 802.3, Relevant 10 Gigabit Ethernet clauses are 49, 10GBASE-R LAN PHY; 50, 10GBASE-W WAN PHY; 10
52, 10 Gigabit Ethernet serial PMDs; and 68, 10GBASE-LRM)
OIF CEI - Optical Internetworking Forum - Implementation Agreement # OIF-CEI-02.0 Common Electrical I/O (CEI)
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(http://www.oiforum.com/public/impagreements.html)
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Acronyms and other abbreviations
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64B/66B
Data encoded with 64B/66B encoder as defined by the IEEE Std. 802.3 CL 49.
BER
bit error ratio
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CDR
clock and data recovery
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CRU
clock recovery unit
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decibel. 10*log10(ratio of power quantities). Powers can be electrical or optical. Conventional usage. See also dBe and 19
dB
dBo.
20
Specific case of dB where signals are electrical. 10*log10(ratio of electrical power quantities). 20*log10(ratio of voltage
dBe
21
quantities) can be used if reference impedances are equal.
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dBm
decibel (relative to 1 mW)
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decibel optical (1 time dBo= 2 time dBe). Specific case of dB where the signals are in optical power. 10*log10(ratio of
optical power quantities). Also, in certain cases with electrical signals relating to linear optical modules, where it is
dBo
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expected that electrical voltage is in proportion to optical power, 10*log10(ratio of voltage quantities).
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DCD
Duty cycle distortion
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DDPWS
Data Dependent Pulse Width Shrinkage
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DDJ
Data Dependent Jitter
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dRN
Difference of Relative noise see Appendix D
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DUT
device under test
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dWDP
Difference of the waveform distortion penalty of an optical receiver
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dWDPc
Difference of the waveform distortion penalty of an electrical cable assembly
EMC
electromagnetic compatibility
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EMI
electromagnetic Interference
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FC
Fibre Channel
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h
hexadecimal notation
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HCB
Host Compliance Board
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IEEE
Institute of Electrical and Electronics Engineers
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ITU-T
ITU Telecommunication Standardization Sector
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Gbit
gigabit = 109 bits
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GBd
Gigabaud
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J2
99% Jitter
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Industry Documents
SFP+ (Active Cable Specifications and Alternate Test Methods)
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MCB
Module Compliance Board
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OMA
optical modulation amplitude
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PCB
printed circuit board
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PRBS9
Pseudo-Random Bit Sequence 2 -1, see SFF-8431 D1.1.1
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PRBS31
Pseudo-Random Bit Sequence 2 -1, see SFF-8431 D1.1.1
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Qsq
Qsq a measure of SNR, see SFF-8431 D1.1.1 and IEEE 802.3.68.6.7
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RI
random interference
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RMS
root mean square
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RN
relative noise
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Rx
receiver
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Rx_LOS
Loss of signal same as defined in FC PI-4 and the inverse of signal detect (SD) in 802.3
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RSS
“Root Sum of Squares”
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SD
Signal Detect
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SerDes
Serializer/Deserializer
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SFI
SFP+ high speed serial electrical interface
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SNR
signal-to-noise ratio
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VccT
Module positive power supply rail for the transmitter
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VccR
Module positive power supply rail for the receiver
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VMA
voltage modulation amplitude
Tx
transmitter
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TWDP
Transmitter Waveform Distortion Penalty for an optical transmitter
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TWDPc
Transmitter Waveform Distortion Penalty of a host transmitter supporting an electrical cable assembly
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UI
unit interval = 1 symbol period
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UJ
Uncorrelated Jitter
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WDP
Waveform distortion penalty
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WDPc
Waveform distortion penalty for an electrical cable assembly
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SFF Specifications
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There are several projects active within the SFF Committee. The complete list of specifications which have been completed or
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are still being worked on are listed in the specification at ftp://ftp.seagate.com/sff/SFF-8000.TXT
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Document Sources
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Those who join the SFF Committee as an Observer or Member receive electronic copies of the minutes and SFF specifications 35
(http://www.sffcommittee.com/ie/join.html).
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Copies of ANSI standards may be purchased from the InterNational Committee for Information Technology Standards
(http://tinyurl.com/c4psg).
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Copies of SFF, T10 (SCSI), T11 (Fibre Channel) and T13 (ATA) standards and standards still in development are available on the 39
HPE version of CD_Access (http://tinyurl.com/85fts).
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LRM
IEEE 802.3 CL68 Physical Layer Specifications for 10Gb/s using 10GBASE-R encoding and long wavelength optics for
multimode fiber
SFP+ (Active Cable Specifications and Alternate Test Methods)
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Conventions
The American convention of numbering is used i.e., the thousands and higher multiples are separated by a comma and a
period is used as the decimal point. This is equivalent to the ISO/IEC convention of a space and comma.
American:
0.6
1,000
1,323,462.9
ISO:
0,6
1 000
1 323 462,9
SFF-8461 Publication History
Revision
Number
0.1
Description
Review draft
SFP+ (Active Cable Specifications and Alternate Test Methods)
Date
Aug. 21, 2009
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SFF-8461, Revision 0.1
Contents
Chapter 1
1.1
1.2
1.3
Active Cabling Specifications
............................................................................... 3
Introduction ............................................................................................................................................................................. 3
Cable Applications Reference Model .............................................................................................................................. 3
10GSFP+Ac Direct Attach Construction......................................................................................................................... 3
SFP+ ACTIVE CABLE HIGH-SPEED ELECTRICAL SPECIFICATION............................................................................. 4
SFP+ ACTIVE CABLES TYPE I (FOR OPERATION WITH A LIMITING HOST) ........................................................... 5
SFP+ ACTIVE CABLES TYPE II .............................................................................................................................................. 5
See D.7 in SFF-8431........................................................................................... .................................................................... 6
Chapter 3
3.1
................................................................................... 1
Introduction ............................................................................................................................................................................. 1
The SFP+ Supported Standards ........................................................................................................................................ 1
ESD............................................................................................................................................................................................... 2
Chapter 2
2.1
2.2
2.3
2.4
2.5
2.6
Table 2
Scope of This Specification
S-Parameters Test Method for 10GSFP+Cu
......................................................... 7
S-Parameters Test Method Procedure............................................................................................................................. 7
3.1.1
3.1.2
3.1.3
Appendix A
MCB-HCB S-Parameters Measurement .........................................................................................................................8
Cable S-parameters Through Measurement...............................................................................................................8
Cable S-parameters Crosstalk Measurement..............................................................................................................9
Matlab Code for S-Parameters Method
SFP+ (Active Cable Specifications and Alternate Test Methods)
............................................................ 11
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List of Tables
Table 1
Table 2
SFP+ Standard Compliance ....................................................................................................... 2
Active Cable Type II Output Specifications at C’................................................................... 6
SFP+ (Active Cable Specifications and Alternate Test Methods
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List of Figures
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
10GSFP+ACA Direct Attach Block Diagram ........................................................................... 4
Active Cable Assembly Test Setup.............................................................................................. 5
MCB-HCB S-parameters Test Setupl......................................................................................... 8
Cable S-Parameters Through Test Setup................................................................................... 9
Cable S-Parameters Through Measurement ........................................................................... 10
SFP+ (Active Cable Specifications and Alternate Test Method)
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SFF-8461
REVISION 0.1
Scope of This Specification
August 21, 2009
DEVELOPMENT
CHAPTER 1 SCOPE OF THIS SPECIFICATION
1.1 INTRODUCTION
This specification defines cabling solutions compatible with SFP+ linear or limiting host for 10.3125 GBd operation based on “SFI”. For detailed SFI specifications and test methodology, see SFF-8431.
This specifications also defines an alternative passive cable test method based
on cable S-parameters. The S-parameters method provides parameters for
cable VMA loss, VCR, dWDP, and Vcm.
SFP+ active and passive cable assemblies are hot pluggable and are powered
by individual power connections for the transmitter (VccT) and the receiver
(VccR). Multiple modules can share a single 3.3 V power supply with individual
filtering for each VccT and VccR. Detailed power supply specifications are given
in SFF-8431 Chapter 2.
The SFP+ cable assemblies compatible with SFI (SFF-8431) could be active-active, active-passive, passive-active, or passive-passive implementations and
may support one or more of the applications listed in Table 1.
SFP+ cable assemblies are either compatible with host supporting linear modules or a host supporting limiting module as defined in SFF-8431 Chapter 3.5.
1.2 THE SFP+ SUPPORTED STANDARDS
SFF-8461 cable assembly may comply with any combination of the standards
shown in Table 1, and may be suitable for other or future standards. This specification does not preclude operation at other signalling rates that are not
listed in this table, such as 2.125 GBd for 2GFC, or 4.25 GBd for 4GFC.
SFP+ (Active Cable Specifications and Alternate Test Methods)
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SFF-8461
REVISION 0.1
Scope of This Specification
August 21, 2009
DEVELOPMENT
.
Standard
Signalling
Rate
(GBd)
IEEE 802.3 Clause 38 or
Clause 59 (1 Gb/s Ethernet)
1.25
8 GFC
8.5
10GSFP+Cu
10.3125
10GSFP+Ac
10.3125
IEEE 802.3 CL 52 (10 Gb/s
Ethernet LAN PHY)
10.3125
IEEE 802.3 CL 52 (10 Gb/s
Ethernet WAN PHY)
9.95328
IEEE 802.3 CL 68 (LRM)
10.3125
10 GFC
10.51875
10GBASE-R (IEEE 802.3
CL 49) Encapsulated in
G.709 ODU-2 Frame
(FEC)
1.3 ESD
11.10
1
2
Table 1 SFP+ Standard Compliance
3
High Speed
High Speed
Low Speed
Low Speed
Management Mechanical/ 4
5
Serial
Serial Test
Electrical
Test Methods
Connector
Interface
Method
Definitions
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7
SFF-8431
Appendix-F
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9
FC-PI-4
FC-PI-4
10
11
SFF-8431
SFF-8431
Chap 3
Appendix D
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Appendix E
and E
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SFF-8431
SFF-8431
SFF-8431
SFF-8432
Chapter 2
SFF-8431
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Chapter 2
Chapter 2
Chap 4
SFF-8083
Appendix D
and
SFF-8472,
15
and E
SFF-8431
SFF-8079,
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Chap 3
SFF-8089
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Appendix E
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SFF-8431
Appendix D
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Chap 3
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The active and passive cable assemblies SFI contacts (High Speed Contacts)
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shall withstand 1000 V electrostatic discharge based on Human Body Model 33
per JEDEC JESD22-A114-B.
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The active and passive cable assemblies contacts with exception of the SFI
36
contacts (High Speed Contacts) shall withstand 2 kV electrostatic discharge
based on Human Body Model per JEDEC JESD22-A114-B.
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The active and passive cable assemblies shall meet ESD requirements given in 39
EN61000-4-2, criterion B test specification such that units are subjected to 15
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kV air discharges during operation and 8 kV direct contact discharges to the
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case.
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SFP+ (Active Cable Specifications and Alternate Test Methods)
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SFF-8461
REVISION 0.1
Active Cabling Specifications
August 21, 2009
DEVELOPMENT
CHAPTER 2 ACTIVE CABLING SPECIFICATIONS
2.1 INTRODUCTION
High speed cabling specifications are based on SFI signalling as defined in SFF8431 supporting either a limiting or linear host. Active cable assemblies may
be used to provide operation over longer or thinner cables than achievable
with direct attach copper assemblies. This section defines electrical specification and compliance testing methodology for such assemblies.
2.2 CABLE APPLICATIONS REFERENCE MODEL
A compliant active cable assembly is designated as 10GSFP+ACA and it can be
identified by reading the memory map of SFF-8472.
The compliance points for SFP+ Active Cables(10GSFP+ACA) are the same as
host compliance test points in 3.3.1 and the module compliance test points in
3.3.2 of SFF-8431.
All SFI test equipment must have 50 Ohms single ended impedance on all test
ports.
Tx_Disable contacts in the module for cable assembly with active transmitter
shall enable or disable the transmitter. For a passive assembly it shall be pulled
to VccT with a 4.7 kΩ to 10 kΩ. The RX_LOS contact in the module for a cable
assembly with active receiver shall be connected to the receiver IC loss of
signal. A passive cable assembly RX_LOS contact shall be pulled low in the
module. Direct connection of RX_LOS to VeeR is allowed for a cable assembly
with passive receiver.
This specification does not assume transmit pre-emphasis beyond the level
defined in SFF-8431.
Warning: 10GSFP+Cu can only be used on systems with common
grounds. Connecting systems with different ground potential with SFP+
direct attach cable results in a short and may cause damage.
2.3 10GSFP+AC DIRECT ATTACH CONSTRUCTION
10GSFP+ACA SFP+ active cable assemblies could be copper or optical, providing either a linear or a limiting output. While particular implementations
SFP+ (Active Cable Specifications and Alternate Test Methods)
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SFF-8461
REVISION 0.1
Active Cabling Specifications
August 21, 2009
DEVELOPMENT
SFP+ (Active Cable Specifications and Alternate Test Methods)
Edge Connector
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2
3
An example of active cable assembly with active transmitter is shown in Figure
4
1. The cable assembly shown has an active transmitter and active receiver.
5
Other implementation possible are active-passive and passive-active. The
6
cable assembly shall incorporate DC blocking capacitors with at least 4.3 V
7
rating between any signal commissioning IC and the SFP+ edge card connector1. The DC blocking capacitor shall have high pass pole of between 20 8
kHz and 100 kHz. For a copper cable assembly, the drain wire is connected to 9
VeeT and to VeeR and the cable shield directly connects the module A and B 10
cases.
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Cable
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SFP+ Module Top View of Board
SFP+ Module Top View of Board
Cable Shield
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DC Blocks
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RDTDIC
IC
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RD+
TD+
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Drain Wire
RD+
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TD+
IC
IC
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TDRDDC Blocks
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10GSFP+Cu
10GSFP+Cu
End A
23
End B
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Figure 1 10GSFP+ACA Direct Attach Block Diagram
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2.4 SFP+ ACTIVE CABLE HIGH-SPEED ELECTRICAL SPECIFICATION
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This section defines the high-speed electrical specification for implementa29
tions with limiting or linear outputs. Active Cables designed to operate with
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limiting hosts are broadly defined as Type I, while Active Cables designed to
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1. SFP+ edge card connector contacts are defined in SFF-8431.
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Edge Connector
are not specified by this standard, it is expected that SFP+ Active Cables operate with either linear or limiting hosts as defined in section X.2.
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SFF-8461
REVISION 0.1
Active Cabling Specifications
August 21, 2009
DEVELOPMENT
operate with linear Hosts are broadly defined as Type II. The test setup for both 1
Type I and Type II Active Cables is shown in Figure 2.
2
3
4
5
Connector
6
C’
Oscilloscope A
7
Trace Length
8
10GSFP+AC
B’
9
A End
Compliance
Signal
10
Generator
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12
MCB 1
Path 1
Path 2
13
14
Connector
C’
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Oscilloscope B
16
Trace Length
10GSFP+AC
17
B End
B’
18
2x50 Ω
19
Termination
20
21
MCB 2
22
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Figure 2 Active Cable Assembly Test Setup
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2.5 SFP+ ACTIVE CABLES TYPE I (FOR OPERATION WITH A LIMITING HOST)
26
SFP+ Active Cable’s Type I are assemblies that operate with the SFP+ limiting 27
hosts defined in Chapter 3 of SFF-8431. Specifically, the active cable input
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must satisfy the SFP+ module transmitter input specifications at B’ in Table 16 29
of SFF-8431 and tolerance specifications at B” in Table 17 of SFF-8431. The ac- 30
tive cable output must satisfy the SFP+ Limiting Module Receiver Output Elec31
trical Specifications at C’ in Table 18 of SFF-8431and the SFP+ Limiting Module
Receiver Output Jitter and Eye Mask Specifications Table 19 of SFF-8431. These 32
output specifications must be met with worst case input allowed by Table 16 33
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and Table 17 of SFF-8431.
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2.6 SFP+ ACTIVE CABLES TYPE II
38
SFP+ Active Cables Type II are cables that operate with the linear hosts defined 39
in Chapter 3 of SFF-8431. To ensure this, SFP+ Active Cables Type II must
40
comply with the following specifications. The active cable input must satisfy
the SFP+ module transmitter input specifications at B’ in Table 16 of SFF-8431 41
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SFP+ (Active Cable Specifications and Alternate Test Methods)
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SFF-8461
REVISION 0.1
Active Cabling Specifications
August 21, 2009
DEVELOPMENT
and tolerance specifications at B” in Table 17 of SFF-8431. The output at C’ of 1
Active Cables Type II must satisfy the requirements of Table 18 of SFF-8431. In 2
addition, it must meet the specifications in Table 2.
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4
Table 2 Active Cable Type II Output Specifications at C’
5
Parameters - C’
Symbol
Conditions
RN
6
RNmax
7
m
b
8
Relative Noise with post-cursor stressor
RN
See 1 and D14.1 in SFF-8431
-0.01
0.12
0.083
9
Parameters - C’
Symbol
Conditions
Min
Max
Unit
10
11
Waveform Distortion Penalty
WDP
See 2 and 3
10
dBe
12
Differential Voltage Modulation Amplitude For LRM
VMA
180
600
mV
13
See D.7 in SFF-8431
14
Differential peak to peak voltage
Vpk-pk
See D.14.3 in SFF-8431
600
mV
15
16
1. Maximum rms RN values are given by the following equation: RN ≤ min[(m*WDP + b), RNmax].
2. Defined with reference receiver with 14 T/2 spaced FFE taps and 5 T spaced DFE taps.
17
3. Worst-case input allowed by the specifications in Table 16 and Table 17 of SFF-8431.
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SFF-8461
REVISION 0.1
S-Parameters Test Method for 10GSFP+Cu
August 21, 2009
DEVELOPMENT
CHAPTER 3 S-PARAMETERS TEST METHOD FOR 10GSFP+CU
S-Parameters test method is an alternate method of calculating 10GSFP+Cu
cable parameters for passive cable assembly. The advantage of the S-parameters method is that it can give consistent results without requiring extensive
adjustment to the SerDes driver. This method gives equivalent result to direct
measurement of cable dWDP, VMA loss, and VCR per definition of SFF-8431 Appendix E.4.
3.1 S-PARAMETERS TEST METHOD PROCEDURE
In order to calculate the cable parameters as defined in SFF-8431 table 37, following test procedure is required:
•
Measure S-parameters for MCB-HCB from point B” to B, see 3.1.1
•
Measure the s4p for through S-parameters for cable end 1 to cable end 2,
see 3.1.2
•
Measure the s4p for crosstalk S-parameters for cable end under test, see
3.1.3
S-Parameter Test Method Matlab code, Appendix A, reads the three S-parameters s4p files in order to calculate the cable parameters dWDP, VMA loss, and
VCR.
3.1.1 MCB-HCB S-PARAMETERS MEASUREMENT
The 4-ports S-parameters for the MCB-HCB response from B” to B is measured
with a Vector Network Analyzer, see Figure 3. The MCB-HCB 4-ports S-parame-
SFP+ (Active Cable Specifications and Alternate Test Methods)
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SFF-8461
REVISION 0.1
S-Parameters Test Method for 10GSFP+Cu
August 21, 2009
DEVELOPMENT
ters are used for S-Parameter Test Method Matlab code calibration, see Appendix A.
1
2
3
4
5
6
Connector
C
C"
7
2x50Ω
2x50Ω
8
MCB
9
HCB
B
B"
10
11
12
13
14
Vector Network Analyzer
15
16
17
18
Port 1 2
3 4
19
20
21
22
Figure 3 MCB-HCB S-parameters Test Setup
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24
25
3.1.2 CABLE S-PARAMETERS THROUGH MEASUREMENT
26
Cable S-Parameters through Measurement setup is shown in Figure 4. The
27
through measurement setup shown is for cable end B to cable end A with the
28
response measured B’ to C’. The procedure is then repeated to measure cable
29
through response from end A to end B.
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Page 8
SFF-8461
REVISION 0.1
S-Parameters Test Method for 10GSFP+Cu
August 21, 2009
DEVELOPMENT
.
1
2
3
Vector Network Analyzer
4
Connector
C’
5
6
7
Path 2
10GSFP+AC
MCB 1
Port 1 2
3 4
B’
8
A End
2x50Ω
9
10
11
12
Path 1
13
Connector
C’
14
2x50Ω
15
10GSFP+AC
16
MCB 2
B End
B’
17
18
19
20
21
Figure 4 Cable S-Parameters Through Test Setup
22
23
3.1.3 CABLE S-PARAMETERS CROSSTALK MEASUREMENT
24
Cable S-parameters crosstalk measurements setup is shown in Figure 5. The 25
crosstalk measurement setup shown is for the cable end B measured from B’ 26
to C’. The procedure is then repeated to measure cable crosstalk for the other
27
end.
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Page 9
SFF-8461
REVISION 0.1
S-Parameters Test Method for 10GSFP+Cu
August 21, 2009
DEVELOPMENT
.
Vector Network Analyzer
C’
Connector
2x50Ω
Port 1
2
3 4
B’
2x50Ω
MCB 1
Path 2
10GSFP+AC
A End
Path 1
C’
B’
Connector
MCB 2
10GSFP+AC
B End
Figure 5 Cable S-Parameters Crosstalk Measurement
SFP+ (Active Cable Specifications and Alternate Test Methods)
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SFF-8461
REVISON 0.1
Matlab Code for S-Parameters Method
August 21, 2009
DEVELOPMENT
APPENDIX A MATLAB CODE FOR S-PARAMETERS METHOD
SFP+ (Active Cable Specifications and Alternate Test Methods)
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