PUBLISHED SFF-8661 Rev 2.4
SFF specifications are available at https://www.sodocs.net/doc/df13275121.html,/sff/specifications
SFF-8661
Specification for
QSFP+ 4X Module
Rev 2.4 October 3, 2017
Secretariat: SFF TA TWG
Abstract: This specification defines the mechanical specifications for the QSFP+ 4x Module Formfactor.
The mechanical dimensioning allows backwards mechanical compatibility between QSFP+ 4X modules plugged into most QSFP+ cages which have been implemented to SFF-8436. The EMI leakage is expected to be similar to that when QSFP+ modules and cages are mated.
Superior EMI performance can only be expected with mated combinations of modules compliant with this specification and cages compliant with SFF-8663 or SFF-8683.
This specification provides a common reference for systems manufacturers, system integrators, and suppliers.
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.
The description of a connector in this specification does not assure that the specific component is actually available from connector suppliers. If such a connector is supplied it must comply with this specification to achieve interoperability between suppliers.
POINTS OF CONTACT: Jay Neer
Molex, LLC.
2222 Wellington Court Lisle, IL 60532
Ph: 561-251-8016
jay.neer@https://www.sodocs.net/doc/df13275121.html, Dan Gorenc
TE Connectivity
3101 Fulling Mill Rd
Middletown, PA 17057
Ph: 717-986-3518
daniel.gorenc@https://www.sodocs.net/doc/df13275121.html,
Chairman SFF TA TWG
Email: SFF-Chair@https://www.sodocs.net/doc/df13275121.html,
PUBLISHED SFF-8661 Rev 2.4 Change History
December 28, 2010:
-Section 3:
o Divided Figure 3-1 into two figures (3-1 and 3-2) and updated titles accordingly
-Section 4:
o Added "Datum Definitions" table
o Updated Figure 4-1 with the following changes:
?Added "Module/Plug" description to top view
?Added appropriate SFF document reference to each view
?Extended datum line through all 3 views
?Replaced "SEE FIGURES 12A AND 12B" WITH "EMI SOLUTION DEPENDENT"
-Section 5:
o Updated Figure 5-1 with the following changes:
?Added note triangle 2 to 32 MIN. dimension
?Added 19 MAX., 13.5 REF., 3.4 MAX. and 1.6 MAX. dimensions o Updated Figure 5-2 with the following changes:
?Added "MAX." and "MIN." to 1.10 / 0.55 dimension (View K-K) o Updated Figure 5-3 with the following changes:
?Replaced SFP+ PCB with QSFP+ PCB
o Updated description of Figure 5-3
-Section 6:
o Updated title (previously was Section 7)
o Replaced Table 7-1 AND 7-2 (SFP+ requirements) with Table 6-1
?Added text to clarify that connector is included in module
insertion/extraction
June 12, 2011:
-Global
o Removed redundant use of 25G throughout body
o All references to 25G were replaced by 32 Gb/s
o Specification Titles updated to current usage
o Added Table of Contents
January 30, 2012:
-All references to 32 Gb/s were replaced by 28 Gb/s
May 21, 2012:
-Expanded list of Industry Documents
July 7, 2012:
-Figure 5-1 was redrawn
o Note 4 was clarified
o Note 9 re higher wattage models added
o Length of transceiver outside of cage restored to the 20 Max of the MSA Rev 1.7 (May 22, 2013):
-Corrected title (removed 'Style')
Rev 1.8 (July 29, 2013):
-Identified Datums to be corrected on Figure 4-1, Figure 5-1 and Figure 5-2
Continued on next page
PUBLISHED SFF-8661 Rev 2.4 Rev 1.9 (October 16, 2013):
-Replaced Figure 4-1
o Sidebar shows how Style A and B create a common figure -Updated Figure 5-1
-Updated Figure 5-2
o Added Datums D and H to Detail 1
-Revised Table 5-1 (was 6-1) cage retention force from 180N to 125N
Rev 2.0 (February 21, 2014):
-Replaced reference to SFF-8436 with EIA 964 in 2-1
-Replaced figures 4-1, 5-1, 5-2 to improve quality
-Deleted two rows in Table 6-1 that did not apply to the Plug/Module
Rev 2.1 (May 25, 2014):
-Restored two rows in Table 6-1 that should not have been deleted
Rev 2.2 (August 7, 2014):
-Replaced Figure 5-2 (the view of section J-J had the radius 0.05 MIN and the dimension 29.60 REF pointing to the wrong location).
Rev 2.3 (September 13, 2014):
-Removed references to 28 Gb/s
Rev 2.4 (October 3, 2017)
-Updated to SNIA format
-Revised abstract
-Reformatted Change History
-Fixed broken links in Foreword
-Updated applications (Section 1.1)
-Added EIA document references
-Clarified “fixed” and “free” definitions
-All references to “pluggable modules,” “plugs,” or “modules” changed to “module;” added definition for “module”
-Minor editorial issues resolved
-Renamed Figure 3-2
-Corrected table in Figure 4-1
-Clarified chamfer/radius callout in Figure 5-2
-Updated Section 5.3 (Insertion, Extraction, and Retention Forces) to agree with other SFF documents for QSFP
PUBLISHED SFF-8661 Rev 2.4
Foreword
The development work on this specification was done by the SNIA SFF TWG, an industry group. Since its formation as the SFF Committee in August 1990, the membership has included a mix of companies which are leaders across the industry.
When 2 1/2" diameter disk drives were introduced, there was no commonality on external dimensions e.g. physical size, mounting locations, connector type, connector location, between vendors. The SFF Committee provided a forum for system integrators and vendors to define the form factor of disk drives.
During their definition, other activities were suggested because participants in SFF faced more challenges than the form factors. In November 1992, the charter was expanded to address any issues of general interest and concern to the storage industry. The SFF Committee became a forum for resolving industry issues that are either not addressed by the standards process or need an immediate solution.
In July 2016, the SFF Committee transitioned to SNIA (Storage Networking Industry Association), as a TA (Technology Affiliate) TWG (Technical Work Group).
Industry consensus is not a requirement to publish a specification because it is recognized that in an emerging product area, there is room for more than one approach. By making the documentation on competing proposals available, an
integrator can examine the alternatives available and select the product that is
felt to be most suitable.
SFF meets during the T10 (see https://www.sodocs.net/doc/df13275121.html,) and T11 (see https://www.sodocs.net/doc/df13275121.html,) weeks, and SSWGs (Specific Subject Working Groups) are held at the convenience of the participants. Material presented to SFF becomes public domain, and there are no restrictions on the open mailing of the presented material by Members.
Many of the specifications developed by SFF have either been incorporated into standards or adopted as standards by ANSI, EIA, JEDEC and SAE.
For those who wish to participate in the activities of the SFF TWG, the signup for membership can be found at:
https://www.sodocs.net/doc/df13275121.html,/sff/join
The complete list of SFF Specifications which have been completed or are currently being worked on by the SFF Committee can be found at:
https://https://www.sodocs.net/doc/df13275121.html,/higherlogic/ws/public/download/47/SFF-8000.TXT
If you wish to know more about the SFF TWG, the principles which guide the
activities can be found at:
https://https://www.sodocs.net/doc/df13275121.html,/higherlogic/ws/public/download/144/8032_028.PDF
Suggestions for improvement of this specification will be welcome, they should be submitted to:
https://www.sodocs.net/doc/df13275121.html,/feedback
PUBLISHED SFF-8661 Rev 2.4
CONTENTS
1.Scope 6
1.1Application Specific Criteria 6
1.2Copyright 6
1.3Disclaimer 7
2.References 7
2.1Industry Documents 7
2.2Sources 7
2.3Conventions 8
2.4Definitions 8
3.General Description 10
4.Datums 11
5.Module Description 13
5.1Dimensions 13
5.2Electrical Interface 15
5.3Insertion, Extraction, and Retention Forces 15
FIGURES
Figure 2-1 Fixed and Free Definition 8 Figure 3-1Typical Module with Copper Cable 10 Figure 3-2Typical Module (Without Cable) 10 Figure 4-1Datum Definitions 11 Figure 5-1Basic Views 13 Figure 5-2Enlarged View of module 14 Figure 5-3Module Electrical Interface 15
TABLES
Table 4-1Datum Definitions 12 Table 5-1Insertion, Extraction, and Retention Values 15
1.Scope
This specification defines the terminology and mechanical requirements for a QSFP+
4x module. This specification is also intended to facilitate the implementation of the 1 x "n" ganged and the 2 x "n" stacked cage configurations based on the mechanical form factor defined in this specification.
The need for this specification became evident when it was realized that some QSFP+ modules and cage designs do not meet the needs for the higher data rates. The QSFP+ is an improved transceiver style which has enhanced EMI characteristics when mated with a cage designed for the module. Please note that there are additional cage requirements specified in this document to allow proper function of the modules in application. These improvements make this module suitable for current QSFP+ applications as well as those at higher transfer rates.
1.1Application Specific Criteria
SAS, InfiniBand, IEEE, and Fibre Channel define respective electrical performance requirements for the transmission of multi-gigabit signals through this interface. When this connector is used for any of these applications, its performance shall meet the requirements of the appropriate standard. This connector shall intermate with previous generations of lower speed QSFP connectors.
1.2Copyright
The SNIA hereby grants permission for individuals to use this document for personal use only, and for corporations and other business entities to use this document for internal use only (including internal copying, distribution, and display) provided that:
1. Any text, diagram, chart, table, or definition reproduced shall be
reproduced in its entirety with no alteration, and,
2. Any document, printed or electronic, in which material from this document
(or any portion hereof) is reproduced shall acknowledge the SNIA copyright
on that material, and shall credit the SNIA for granting permission for its
reuse.
Other than as explicitly provided above, there may be no commercial use of this document, or sale of any part, or this entire document, or distribution of this document to third parties. All rights not explicitly granted are expressly reserved to SNIA.
Permission to use this document for purposes other than those enumerated (Exception) above may be requested by e-mailing copyright_request@https://www.sodocs.net/doc/df13275121.html,. Please include the identity of the requesting individual and/or company and a brief description of the purpose, nature, and scope of the requested use. Permission for the Exception shall not be unreasonably withheld. It can be assumed permission is granted if the Exception request is not acknowledged within ten (10) business days of SNIA's receipt. Any denial of permission for the Exception shall include an explanation of such refusal.
1.3Disclaimer
The information contained in this publication is subject to change without notice. The SNIA makes no warranty of any kind with regard to this specification, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose. The SNIA shall not be liable for errors contained herein or for incidental or consequential damages in connection with the furnishing, performance, or use of this specification.
Suggestions for revisions should be directed to https://www.sodocs.net/doc/df13275121.html,/feedback/
2.References
2.1Industry Documents
-Ethernet IEEE 802.3ba 40G
-Ethernet IEEE 802.3bj 100G
-InfiniBand IBTA QDR/FDR/EDR
-T10 SAS-2.1 (Serial Attached SCSI)
-T10 SAS-3
-T11 FC-PI-5 (Fibre Channel Physical Interface)
-T11 FC-PI-6
-EIA-964 QSFP+ 10 Gb/s 4X Pluggable Transceiver
-SFF-8024 SFF Committee Cross Reference to Industry Product Names
-SFF-8410 High Speed Serial Testing for Copper Links
-SFF-8635 QSFP+ 10 Gb/s 4X Pluggable Transceiver Solution (QSFP10)
-SFF-8662 QSFP+ 28 Gb/s 4X Connector (Style A)
-SFF-8665 QSFP+ 28 Gb/s 4X Pluggable Transceiver Solution (QSFP28)
-SFF-8672 QSFP+ 28 Gb/s 4X Connector (Style B)
-SFF-8682 QSFP+ 4X Connector
-SFF-8683 QSFP+ Cage
-SFF-8685 QSFP+ 14 Gb/s 4X Pluggable Transceiver Solution (QSFP14)
-EIA-364-1000 Environmental Test Methodology for Assessing the Performance of Electrical Connectors and Sockets Used in Controlled Environment Applications -EIA-364-13 Mating and Unmating Forces Test Procedure for Electrical Connectors 2.2Sources
There are several projects active within the SFF TWG. The complete list of specifications which have been completed or are still being worked on are listed in https://https://www.sodocs.net/doc/df13275121.html,/higherlogic/ws/public/download/47/SFF-8000.TXT
Copies of ANSI standards may be purchased from the InterNational Committee for Information Technology Standards (https://www.sodocs.net/doc/df13275121.html,/incitsgate.tmpl).
2.3Conventions
The dimensioning conventions are described in ANSI-Y14.5M, Geometric Dimensioning and Tolerancing. All dimensions are in millimeters, which are the controlling dimensional units (if inches are supplied, they are for guidance only).
The ISO convention of numbering is used i.e., the thousands and higher multiples are separated by a space and a period is used as the decimal point. This is equivalent to the English/American convention of a comma and a period.
American French ISO
0.6 0,6 0.6
1,000 1 000 1 000
1,323,462.9 1 323 462,9 1 323 462.9
2.4Definitions
For the purpose of SFF Specifications, the following definitions apply:
Advanced grounding contacts: Connector contacts that mate first and break last and are capable of carrying power ground return currents and performing electrostatic discharge. Other terms sometimes used to describe these features are: grounding pins, ESD contacts, grounding contacts, static drain, and pre-grounding contacts.
Alignment guides: Connector features that preposition insulators prior to
electrical contact. Other terms sometimes used to describe these features are: guide pins, guide posts, blind mating features, mating features, alignment features, and mating guides
Contact mating sequence: Order of electrical contact during mating/unmating process. Other terms sometimes used to describe this feature are: contact sequencing, contact positioning, make first/break last, EMLB (early make late break) staggered contacts, and long pin / short pin.
Fixed: Adopted from EIA standard terminology as the gender that most commonly
exists on the fixed end of a connection, for example, on the board or bulkhead side. In this specification "fixed" is specifically used to describe the mating side gender illustrated in Figure 2-1. It is typically used to describe the gender of the mating side of the connector that accepts its mate upon mating. Other common terms are “receptacle,” “female,” and “socket connector.”
Free: Adopted from EIA standard terminology as the gender that most commonly exists on the free end of a connection, for example, on the cable side. In this
specification "free" is specifically used to describe the mating side gender illustrated in Figure 2-1. It is typically used to describe the gender of the mating side of the connector that penetrates its mate upon mating. Other common terms are "plug” or “module," "male," and "pin connector.”
FIGURE 2-1 FIXED AND FREE DEFINITION
PUBLISHED SFF-8661 Rev 2.4
Module: In this specification, refers to direct attach copper (DAC), direct attach optics, and pluggable optics.
Optional: This term describes features which are not required by the SFF Specification. However, if any feature defined by the SFF Specification is implemented, it shall be done in the same way as defined by the Specification. Describing a feature as optional in the text is done to assist the reader. If there is a conflict between text and tables on a feature described as optional, the table shall be accepted as being correct.
Surface mount: A connector design and a printed circuit board design style where the connector termination points do not penetrate the printed circuit board and are subsequently soldered to the printed circuit board. Other common terms are “surface mount technology” or “SMT.”
Through hole: A connector design and a printed circuit board design style where the connector termination points penetrates the printed circuit board and are subsequently soldered to the printed circuit board. Other common terms are “plated through hole” or “PTH.”
3.General Description
This specification defines the complete mechanical dimensions of the QSFP+ 4x module. This module provides interoperability and EMI control for the QSFP system. The dimensions for the module are normative.
FIGURE 3-1 TYPICAL MODULE WITH COPPER CABLE
FIGURE 3-2 TYPICAL MODULE (WITHOUT CABLE)
4.Datums
FIGURE 4-1 DATUM DEFINITIONS
TABLE 4-1 DATUM DEFINITIONS
5.Module Description
5.1Dimensions
FIGURE 5-1 BASIC VIEWS
FIGURE 5-2 ENLARGED VIEW OF MODULE
5.2Electrical Interface
The QSFP+ module contains a printed circuit board that mates with an appropriately designed connector. The pads are designed for a sequence mating:
?First mate: Ground contacts
?Second mate: Power contacts
?Third Mate: Signal contacts
FIGURE 5-3 MODULE ELECTRICAL INTERFACE
Note: View is shown for reference only. See appropriate specfication for dimensional values. Seee the appropriate standard for the pad layout and definitions.
5.3Insertion, Extraction, and Retention Forces
TABLE 5-1 INSERTION, EXTRACTION, AND RETENTION VALUES
Parameter Procedure Requirement1 Insertion force EIA 364-13
Test with connector, cage & module
(latch disengaged, without heatsink)
60N MAX
Extraction force EIA 364-13
Test with connector, cage & module
(latch disengaged, without heatsink)
30N MAX
Latch strength Pull to separate module from cage
Test with connector, cage & module
(latch engaged)
125N MIN
Bulk cable retention in module2Pull to separate bulk cable from module
Test with cable assembly only
90N MIN
Module durability Test with connector, cage & module as part
of TS-1000350 cycles
MIN
NOTES:
1.In addition to the requirements listed, all parts must be free of
visible damage after testing.
2.Does not apply to pluggable optical modules.
3.Modules may be replaced every 50 cycles.