AMPHENOL TCS
TB-2082
DFM and SMT Assembly Guideline
Revision “F“
Specification Revision Status
Revision
“-“
“A”
“B”
“C”
SCR No.
33277
36994
39831
42921
Description
Initial Release
Update stencil design, JEDEC tray info, add weight
table & GenRad ref, delete AirVac detail.
Revised in it’s entirety and reformatted.
Clarify board warp req, add stand-off req, change
handling to reflect new packaging, changes to paste
process – add selection matrix, reflow process –
additional thermal probe and plug note, and reflow
verification and de-bug.
Replaced template format
Updated copyright information
Changed reference of solder ball diameter to 28mil
Added Lead-Free information
Modified the solder paste aperture recommendations
for the 28mil solder ball
Added Pin A1 alignment and more reflow profile info.
Initial
J. Marvin
J. Proulx
J. Proulx
J. Proulx
Date
1/16/01
10/19/01
9/17/02
8/13/03
“D“
‘E’
‘F’
S0043
S0802
S1760
M.Lee
C Palmer
J. Proulx
02/07/06
02/26/08
6/09/11
Amphenol TCS
200 Innovative Way, Suite 201
Nashua, NH 03062
603.879.3000
www.amphenol-tcs.com
DFM and SMT Assembly Guideline
Table of Contents
1.0
DFM Guideline Introduction
1.1
Scope
1.2
Purpose
1.3
Reference Documents
1.3.1
Customer Use Drawings
Design Introduction – NeXLev Connector
Design Requirements
3.1
NeXLev Solder Joint Definition – Reliability Factors
3.2
Landing Pad Footprint
3.3
PCB General Requirements and Suggested Routing
TB-2082
Revision “F“
2.0
3.0
3.4
3.5
3.6
3.7
3.8
3.9
4.0
5.0
6.0
7.0
Connector Pin A1 Alignment
Connector Float Allowance and PCB Fabrication Tolerances
Layout and Orientation for Multi-Connector Applications
Mechanical Requirements - Standoffs
Keep-out Zone and Clearances – Connector height < 10.5mm
Keep-out Zone and Clearances – Multi Connector and Connector height > 15.5mm
Manufacturing Introduction
4.1
Connector Inspection
Connector Handling
Solder Paste Process
Placement Process
7.1 Placement Alignment – “Best-Fit”
7.2 Placement - 15.5 and 23.5mm Receptacles
7.3 Feeders
7.4 JEDEC Tray Set-up
Reflow Process
8.1
Reflow Process – Reflow Profile Recommendations
8.2 Reflow Process – Detailed Verification and De-bug
8.3 Vacuum “Pick-up” Cap Removal
Double Sided Reflow Process
8.0
9.0
10.0 Rework Process
Addendums:
A. NeXLev Connector Weights
B. NeXLev DFM Check Sheet - used for design reviews, and process start-up.
Copyright © Amphenol Corporation 2011 • All rights reserved
Page 2 of 31
DFM and SMT Assembly Guideline
1.0
DFM Guideline Introduction
TB-2082
Revision “F“
This document is intended to provide design criteria and process information that will promote
automation, cost and cycle time reduction, and help to produce designs that will yield high quality for the
solder attach of NeXLev connectors. The NeXLev connector will be used in many assembly processes,
and because all processes are different, this document provides a starting point, or “baseline” criteria for
application process development.
This document is not intended to be the final process definition,
nor is it intended to constrain designs.
If customers cannot meet/follow all of the recommendations,
they should contact TCS to discuss the best alternatives.
1.1
Scope
This document has been prepared to communicate the application guidelines for the NeXLev
Surface Mount Connector. It provides Printed Circuit Board (PCB) footprint and layout criteria, and
“starting-point” process recommendations for SMT assembly. Updates and revisions will be issued on a
continuous basis to expand the guidelines, address changes in technology and manufacturing
capabilities, and cover modifications and/or additions to current criteria.
1.2
Purpose
DFM is the sharing of manufacturing guidelines developed from industry standards and the
knowledge gained from design and production. Applying these guidelines concurrently, in new product
development with the design and application of Amphenol TCS’s NeXLev connector, can positively
impact cost, time to market, and quality of the end product.
1.3
Reference Documents
Located at: http://www.Amphenol TCS.com/prods/tcs/products/hpi/NeXLev/drawings.html
1.3.1
Customer Use Drawings
C-471-1025-500
C-470-1075-500
471-1025-500
470-1075-500
Plug (drawing for application)
Receptacle (drawing for application)
Plug (drawing for inspection)
Receptacle (drawing for inspection)
1.4
Levels of Requirement
For each requirement, an impact and benefit statement is included to quantify the requirement.
Some requirements are stated as being recommended or preferred per the following:
Recommended:
The minimum processing requirement – a deviation
will
most likely impact
manufacturability and cost.
Preferred:
Should be done when possible – a deviation
could
impact manufacturability and
cost.
Copyright © Amphenol Corporation 2011 • All rights reserved
Page 3 of 31
DFM and SMT Assembly Guideline
2.0 Design Introduction – NeXLev Connector
TB-2082
Revision “F“
The NeXLev connector is a wafer construction organized in a 10-row by up to 30 columns of
signal contacts, with each signal wafer having integral strip-line shielding. This wafer construction
allows for the contacts to be spaced on a 1.5mm x 1.75mm grid. The connector can be specified in
separation heights ranging from 10mm to 30mm.
The connector is a completely SMT attach, utilizing ball grid technology for termination to the
board. Designed with solder joint reliability in mind, the connector has a mechanically compliant
structure, and is readily applied using standard SMT processes. Standard versions of the NeXLev
connector contain either 10, 20 or 30 wafers. (100, 200, or 300 positions)
The connector is different than a standard BGA device, due to the compliant structure, which has
a 0.71 mm (28mil) solder ball, re-flowed on the end of a formed pedestal. There are two solder ball
alloys available – Tin/Lead (eutectic) or Lead Free (SAC305).
One wafer contains 10 signal and 9 ground
balls and the connector is provided in 10,
20, and 30 wafer configurations.
S-Bend
Compliant Lead
Ground Shield
Ball is attached to a
pedestal at the end of
the “S-Bend”
Compliant Lead
Copyright © Amphenol Corporation 2011 • All rights reserved
Page 4 of 31
DFM and SMT Assembly Guideline
3.0 Design Requirements
3.1 NeXLev Solder Joint Definition – Reliability Factors
TB-2082
Revision “F“
The recommendations made below have a direct impact on the reliability of the NeXLev solder joint,
and play an important role in facilitating the connectors' ability to self-center and achieve the best possible
location tolerances. This is especially important when multiple connectors are being used.
Requirements
•
Recommend using a “Copper Defined”
landing pad as opposed to a “Solder-
Mask Defined” pad.
•
Pad Size = .60mm (.024”)
DFM Impact/Benefit
•
“Copper defined” better insures a round, accurately located
pad – critical to part location tolerance.
•
“Copper defined” pad produces a more reliable solder joint –
allowing solder to wrap around the pad edge.
•
Smaller pad will result in decreased ball-to-pad angle,
based on solder volume – increasing the risk of solder
fracture.
•
Larger pads will increase the risk of shorting.
•
In-accurate registration will result in solder mask
encroaching onto copper pad.
•
Solder mask should be clear around pad
Angle is critical to solder
joint reliability – a
smaller pad will result in
a fatter ball, decreasing
angle and creating weak
points in the joint
S-Bend Compliant
Lead
Solder mask is clear
around pad
Solder Mask
PCB
Copper Pad
Copper defined pad yields highest quality solder joint –
compared to Solder Mask defined:
-
Doesn’t inhibit connectors ability to self-center
-
Solder wraps around pad edge - maximum strength
Copyright © Amphenol Corporation 2011 • All rights reserved
Page 5 of 31