SFF specifications are available at http://www.snia.org/sff/specifications   
                                  or ftp://ftp.seagate.com/sff  
 
 
 
 
 
This specification was developed by the SFF Committee prior to it 
becoming the SFF TA (Technology Affiliate) TWG (Technical Working 
Group) of SNIA (Storage Networking Industry Association). 
 
 
 
 
 
 
 
 
 
 
Chairman SFF TA TWG  
Email: SFF-Chair@snia.org  
 
 
 
 
 
The information below should be used instead of the equivalent herein. 
 
POINTS OF CONTACT:  
 
 
 
 
 
 
If you are interested in participating in the activities of the SFF TWG, the 
membership application can be found at: 
 
 
The complete list of SFF Specifications which have been completed or are currently 
being worked on can be found at: 
 
 
The operations which complement the SNIA's TWG Policies & Procedures to guide the SFF 
TWG can be found at: 
 
 
 
Suggestions for improvement of this specification will be welcome, they should be 
submitted to: 
 
 
 
 
http://www.snia.org/feedback 
http://www.snia.org/sff/specifications/SFF-8000.TXT 
http://www.snia.org/sff/specifications/SFF-8032.PDF 
http://www.snia.org/sff/join 
 
 
 
 
 
 
 
 
 
 
 Published                                                         SFF-8643 Rev 3.5 
 
 SFF Committee documentation may be purchased in electronic form. 
 SFF specifications are available at ftp://ftp.seagate.com/sff 
 
 
 
 
 
 
 
 
 
SFF Committee 
SFF-8643 Specification 
for 
Mini Multilane 4/8X 12 Gb/s Unshielded Connector (HD12un) 
Rev 3.5    September 22, 2014 
 
 
 
 
 
Secretariat:  SFF Committee  
 
Abstract: This specification defines the general performance requirements for the 
Mini Multilane connector, which is designed for use in high speed serial, 
interconnect applications at multi-gigabit speeds. This connector is popularly 
referred to as the Mini-SAS HD (High Density) Connector system.  
 
This is the first generation of this connector. 
 
This specification provides a common reference for systems 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. 
 
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. 
 
Support: This specification is supported by the identified member companies of the 
SFF Committee. 
 
 
 
POINTS OF CONTACT: 
 
 
 Jay Neer    
 
 
 Technical Editor  
 Molex 
 
 
 2222 Wellington Court   
 Lisle, Il 60532  
 Ph: 561-447-2907x555-3889    
 Email: jay_dot_neer_at_molex_dot_com 
I. Dal Allan 
Chairman SFF Committee 
14426 Black Walnut Court 
Saratoga, CA 95070 
Ph: 408-867-6630 
Email: endlcom_at_acm_dot_org  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Mini Multilane 4/8X 12 Gb/s Unshielded Connector (HD12un)                   Page 1  
 Published                                                         SFF-8643 Rev 3.5 
 
                      EXPRESSION OF SUPPORT BY MANUFACTURERS 
 
The following member companies of the SFF Committee voted in favor of this industry 
specification. 
 
               All Best 
               Amphenol 
               Avago 
               Cinch 
               Dell Computer 
               Emulex 
               FCI 
               GLGnet Electronics 
               Hewlett Packard 
               HGST 
               Jess-Link 
               LSI 
               Luxshare-ICT 
               Luxtera 
               Molex 
               NetApp 
               NetLogic uSyst 
               Panduit 
               Seagate 
               Shinning Electronics 
               TE Connectivity 
               Volex 
               Xyratex 
 
 
The following member companies of the SFF Committee voted against this industry 
specification. 
 
               Foxconn 
 
 
The following member companies of the SFF Committee voted to abstain on this 
industry specification. 
 
               AMI 
               Applied Micro 
               Broadcom 
               EMC 
               Finisar 
               JDS Uniphase 
               Mellanox 
               MGE 
               Oclaro 
               Pioneer 
               QLogic 
               Sandisk 
               Sumitomo 
               Toshiba 
               Western Digital 
                
 
The user's attention is called to the possibility that implementation to this 
Specification may require use of an invention covered by patent rights. By 
distribution of this Specification, no position is taken with respect to the 
Mini Multilane 4/8X 12 Gb/s Unshielded Connector (HD12un)                   Page 2  
 Published                                                         SFF-8643 Rev 3.5 
 
validity of this claim or of any patent rights in connection therewith. Members of 
the SFF Committee, which advise that a patent exists, are required to provide a 
statement of willingness to grant a license under these rights on reasonable and 
non-discriminatory terms and conditions to applicants desiring to obtain such a 
license.  
 
Change History: 
 
Rev 2.1 November 5, 2010: 
- Dimension designators changed to alpha order for Figures 6.2 through 6.8. 
Rev 2.3 January 11, 2011 
- Title changed to "Unshielded 8/4 Channel for 12 Gb/s Applications" 
- Changed A11 from 0.105 +/- 0.025 to 0.10 +/- 0.05  
- Added note to E01 to clarify contact zone 
- Figure 6.8 and Table 6.8 - 1x4 removed 
Rev 2.6 August 9, 2012 
- Editorial revision to adopt latest template 
- Removed electrical performance requirements specified by the using interface 
- Simplified titling of sections, figures and tables 
- Replaced double drawings of Figure 2-1 
- Sections made consistent between SFF-8643 and SFF-8644  
Revision 2.7 April 22, 2013 
- Adopt editorial convention of Gb/s  
Revision 2.8 June 3, 2013 
- Added appropriate figures for the new vertical versions 
- Dimensioned the keep-out areas in the connector footprints 
- Added rib to top of the right angle latch area 
Revision 2.9 July 10, 2013 
- Expanded Figure 3-1 to include more configurations 
- Redrew figures and clarified dimensioning on vertical configurations  
Revision 3.0  July 27, 2013 
- Corrected some dimensions in Tables 6-1, 6-2 and 6-4  
Revision 3.1  August 22, 2013 
- Updated dimensions in Tables 6-1, 6-2 and 6-4  
- Added R(ight angle) and V(ertical) suffixes to Tables 6-1 and 6-2  
- Added optional holes to Figures 6-10 and 6-12 
Revision 3.2  February 26, 2014 
- Revised description 3.0 
- Updated Table 3-1 to list all versions 
- Revised designators in Tables 6-1 and 6-2 
- Removed revision note below Table 6-4 
- Revised Table 6-5 dimensions 
Revision 3.3  May 15, 2014 
 - Title change for commonality in style with QSFP 
Revision 3.4 May 25, 2014 
- Revised dimensions in Figures 6-1 and 6-2 
- Added 6.2 section Title 
- Revised Figure 6-7 and Table 6-3 titles 
- Revised Titles for Figure 6-8 and Table 6-4 
- Revised Table 6-4 to add the 1x2 size 
- Revised text with section 6.3 and the section Title 
- Revised Table 6-5 descriptions 
- Revised Figure 6-12 Title 
- Revised Figure 6-14 Title 
Revision 3.5  September 22, 2014  
- The connector content of this specification was used to create SFF-8613 
Mini Multilane 4/8X 12 Gb/s Unshielded Connector (HD12un)                   Page 3  
 Published                                                         SFF-8643 Rev 3.5 
 
 
Foreword  
 
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.  
 
When 2 1/2" diameter disk drives were introduced, there was no commonality on 
external dimensions e.g. physical size, mounting locations, connector type, and 
connector location, between vendors.  
 
The first use of these disk drives was in specific applications such as laptop 
portable computers and system integrators worked individually with vendors to 
develop the packaging. The result was wide diversity, and incompatibility. 
 
The problems faced by integrators, device suppliers, and component suppliers led to 
the formation of the SFF Committee as an industry ad hoc group to address the 
marketing and engineering considerations of the emerging new technology.  
 
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 
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.  
 
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 
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 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 
restrictions on the open mailing of material presented at committee meetings.  
 
Most of the specifications developed by the SFF Committee have either been 
incorporated into standards or adopted as standards by EIA (Electronic Industries 
Association), ANSI (American National Standards Institute) and IEC (International 
Electrotechnical Commission). 
 
If you are interested in participating or wish to follow the activities of the SFF 
Committee, the signup for membership and/or documentation can be found at: 
 
 
The complete list of SFF Specifications which have been completed or are currently 
being worked on by the SFF Committee can be found at:  
 
 
If you wish to know more about the SFF Committee, the principles which guide the 
activities can be found at:  
 
 
Suggestions for improvement of this specification will be welcome. They should be 
sent to the SFF Committee, 14426 Black Walnut Ct, Saratoga, CA 95070. 
 
http://www.sffcommittee.com/ie/join.html 
ftp://ftp.seagate.com/sff/SFF-8032.TXT 
ftp://ftp.seagate.com/sff/SFF-8000.TXT 
 
 
 
 
 
 
Mini Multilane 4/8X 12 Gb/s Unshielded Connector (HD12un)                   Page 4  
 Published                                                         SFF-8643 Rev 3.5 
 
 
TABLE OF CONTENTS    
1  Scope 
1.1 
Application Specific Criteria 
2  References 
Figure 3-1 Documentation to Implement a 12 Gb/s Connector 
Figure 4-1 General View of Configurations 
 
FIGURES 
TABLES 
Table 4-1 Configurations 
 
Industry Documents 
SFF Specifications 
Sources 
Conventions 
3  Description 
4  Overview of Referenced Specifications 
Application Requirements 
SFF-8613 
2.1 
2.2 
2.3 
2.4 
4.1 
4.2 
 
6 
6 
6 
6 
6 
6 
6 
7 
7 
7 
8 
7 
8 
8 
Mini Multilane 4/8X 12 Gb/s Unshielded Connector (HD12un)                   Page 5  
 Published                                                         SFF-8643 Rev 3.5 
 
1  Scope 
This specification defines the performance requirements of the Mini Multilane 
unshielded connector.  
1.1  Application Specific Criteria 
This connector is capable of meeting the interface requirements for the high 
density internal I/O requirements of T10 SAS-3.   
2  References 
2.1  Industry Documents  
The following interface standards and specifications are relevant to this 
Specification. 
 
 - INCITS 519   SAS-3 (Serial Attached SCSI 3)  
 - SFF-8410     High Speed Serial Testing for Copper Links 
 - SFF-8613     Mini Multilane 4/8X Unshielded Connector 
 - SFF-8614     Mini Multilane 4/8X Shielded Connector 
 - SFF-8644     Mini Multilane 4/8X 12 Gb/s Shielded Connector 
2.2  SFF Specifications  
There are several projects active within the SFF Committee. The complete list of 
specifications which have been completed or are still being worked on are listed in 
the specification at ftp://ftp.seagate.com/sff/SFF-8000.TXT 
2.3  Sources  
Those who join the SFF Committee as an Observer or Member receive electronic copies 
of the minutes and SFF specifications (http://www.sffcommittee.com/ie/join.html). 
 
Copies of ANSI standards may be purchased from the Inter-National Committee for 
Information Technology Standards (http://tinyurl.com/c4psg). 
 
Copies of SFF, ASC T10 (SCSI), T11 (Fibre Channel) and T13 (ATA/SATA) standards and 
standards still in development are available on the HPE version of CD_Access 
(http://tinyurl.com/85fts).  
 
2.4  Conventions 
The dimensioning conventions are described in ANSI-Y14.5M, Geometric Dimensioning 
and Tolerancing. All dimensions are in millimeters. 
 
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 
         0.6 
     1,000 
 1,323,462.9 
French 
        0,6 
    1 000 
1 323 462,9 
ISO 
        0.6 
    1 000 
1 323 462.9 
 
 
Mini Multilane 4/8X 12 Gb/s Unshielded Connector (HD12un)                   Page 6  
 Published                                                         SFF-8643 Rev 3.5 
 
3  Description 
This specification identifies the documentation required to implement a 12 Gb/s 
unshielded connector suitable to the using applications, as illustrated in the  
following pictorial representation. 
 
 
 
 
 
SAS-3 
Application 
Interface 
 
 
 
 
 
 
 
 
SFF-8643 
Connector  
Assembly 
SFF-8613 
Connector 
Mechanical 
FIGURE 3-1 DOCUMENTATION TO IMPLEMENT A 12 GB/S CONNECTOR 
 
4  Overview of Referenced Specifications 
4.1   Application Requirements  
The electrical and EMI considerations for the use of this connector are specified 
by the using standards listed in Section 1.1. 
 
This connector system is based upon vertical and  right angle receptacle (fixed)  
connectors and (free) mating plugs. The host board footprint mounting holes contain  
the critical dimensions for locating the receptacles to the host board. The  
integral receptacle guide shell functions as the guide and strain relief for the  
free (plug) connector interface and also provides the latching points for the plug  
connector. This connector system provides positive retention along with ease of  
insertion and removal. 
Mini Multilane 4/8X 12 Gb/s Unshielded Connector (HD12un)                   Page 7