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Peter Burnley MIT Technology Centre Manager Electronics Yorkshire Eric HinsleySenior TutorElectronics Yorkshire. Introduction to IPCOverview of IPC Design
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2. Peter Burnley MIT
Technology Centre Manager
3. Introduction to IPC
Overview of IPC Design & Acceptance Standards
Implementation of a Manufacturable Design
Quality & Inspection
Founded in 1957 by six companies, IPC was established as an association to assist the printed circuit board industry in flourishing. Focusing our efforts on design, manufacturing and assembly of printed circuit boards, IPC has grown to over 2300 member companies worldwide. Founded in 1957 by six companies, IPC was established as an association to assist the printed circuit board industry in flourishing. Focusing our efforts on design, manufacturing and assembly of printed circuit boards, IPC has grown to over 2300 member companies worldwide.
4. IPC is a Technical Organization that meets Industry Requirements as it is driven by Industry
There are many committees that sit regularly to discuss the changes that are happening in the industry
The standards and certifications are updated regularly Founded in 1957 by six companies, IPC was established as an association to assist the printed circuit board industry in flourishing. Focusing our efforts on design, manufacturing and assembly of printed circuit boards, IPC has grown to over 2300 member companies worldwide. Founded in 1957 by six companies, IPC was established as an association to assist the printed circuit board industry in flourishing. Focusing our efforts on design, manufacturing and assembly of printed circuit boards, IPC has grown to over 2300 member companies worldwide.
5. Applicable IPC Standards 4 Design -7351; Land Pattern Considerations (IPC782)
-7095; BGA Process Implementation
-2315; HDI & Microvia Design Guide
-2220; Design for Manufacture
-D-279; Design for SMT Reliability
J-STD-001; Soldering Requirements
-A-610; Assembly Acceptability
-6010; Printed Board Series
J-STD-004/005; Solder Flux/Paste
IPC-1752; Material Declaration
6. International Organizations ISO - International Organization for Standardization
Deals mostly with Mechanical Standards
IEC - International Electrotechnical Commission
Deals mostly with Electrical / Electronic Standards.
Both ISO & IEC managed from same location in Geneva, Switzerland
Occasional overlap between ISO and IEC programming
Both require participating Country support
7. IPC defines 3 levels of product quality for Manufactures to build to and designers to aim for.
Class 1 - General Electronic Products
Class 2 - Dedicated Service Electronic Products
Class 3 - High Reliability Electronic Products
There are more defined classifications within the sub categories of IPC standards
8. Overview of IPC Design & Acceptance Standards
9. Design & Acceptance Covers
The guidelines are constantly evolving on Rigid, Flex boards and assemblies, pc cards, modules, embedded passive components
Other new technologies intended to address tighter tolerances, greater electrical capabilities and increased product performance requirements.
Consideration is also given on CAD/CAM capability and data transfer from supply source.
10. Electronic Equipment Design IPC-2221
Generic Standard on Printed Board Design
Sectional Standard on Rigid Organic Printed Boards
Sectional Design Standard for Flexible Printed Boards
Sectional Standard of Design of PWB for PC Cards
Sectional Design Standard for Organic Multichip Modules (MCM-L) and MCM-L Assemblies
Sectional Design Standard Guide for High Density Interconnects & Microvias
Design Guide for High Density Interconnects & Microvias
Design Guide for Embedded Component Technology(will become IPC-2227)
11. Whats Involved in theDocumentation Package Fabrication Drawings
Bill of Materials
Schematic or Logic Diagrams
Specification Control Drawings
12. Design Issues Land pattern concepts
Mounting substrate design
Method of test
Meeting solder joint requirements
Stencil fixture requirements
Providing access for inspection
Access for rework and repair
13. Manufacturing Allowance The courtyard represents the starting point of the minimum area needed for the component and the land pattern
Manufacturing allowance must be considered in the design process
Manufacturing, assembly and testing representatives should be involved in determining the additional room needed to accommodate placement, testing, modification and rework
14. IPC-7351 Land Pattern Software
15. Whats Next? New Design Standards
Major support by CAD tool providers
National Institute Standard Technology (NIST) viewer can be used to check data files
NIST Gerber to IPC-2581 conversion
New tools becoming available daily
16. Material Selection
17. Material Requirements Cover Existing standards
New materials being developed to meet higher temperature assembly due to lead free implementation
Requirement for halogen free laminate
18. Standards for Laminates Flexible Laminate
Rigid and HDI Laminate
19. PCB Base Material Base materials for printed board applications are changing faster than at any point in their short 45 year history.
FR-4 is improving technically to facilitate
Global market place requires global specifications
With new materials and technologies developed rapidly, governing standards must be generated just as fast in order to maintain a cohesive pattern of control
20. Key Material Properties
21. Solder Alloy Selection
22. Printed Board Process Characteristics
23. Surface Finish HASL - hot air solder leveling
OSP - organic solderability preservative
ENIG - electro less nickel immersion gold
ImAg - immersion silver
ImSn - immersion tin
New Developments include DIG
Direct Immersion Gold
24. Related Process Issues Solder paste application (volume
Tented or plugged vias
Solder flux removal vs flux residue
Impact of wave soldering
Partially filled vias
25. Workmanship &Discrimination Standards
26. Standards of Workmanship
Any training provided should be across the board and not just to operators so that everyone understands the design and performance intent.
Discuss both the mounting structure and the assembly end product characteristics
Need for describing the manufacturing target condition
Compares acceptable workmanship as well as rejected or process indicator criteria.
27. Acceptance IPC-A-600G
Acceptability of Printed Boards
Acceptability of Electronic Assemblies
Requirements & Acceptance for Cable & Wire Harness Assemblies
28. Workmanship IPC J-STD-001D
Requirements for Soldering Electrical & Electronic Assemblies
IPC-7711A & IPC-7721A
Rework of Electronic Assemblies
Repair and Modification of PCBs and electronic Assemblies
30. Acceptance Acceptance of product for delivery shall be based on product that has passed the testing requirements shown in the applicable Performance Specification and User defined documentation.
31. Quality and Inspection
32. Quality Assessment Covers existing standards
Test method and techniques used to evaluate the products that are part of the electronic equipment
Addresses techniques for process control, how these should be applied and sampling plan characteristics
Industry best practice criteria for the products in question.
33. Process Control Elements Key Process Control Variables
Design For Manufacture (DFM)
34. Key Considerations forImproving Yield Finer the pitch, more difficult is the implementation of design & manufacture.
With reduced pitch, precision becomes more intense and process windows tighten
Lower yield and higher cost if design is not precise and processes are not very tightly controlled
With the widespread use of smaller and smaller components with finer and finer pitches, the problem is simply compounded
35. Common Quality Control Techniques: Trial and Error Trial Error methods are expensive, time consuming and can be frustrating.
The processes are incredibly high speed.
They must be performed by machines.
The equipment must be thoroughly characterized.
Most large companies have assigned engineers to optimize; small companies learn as they go.
Learn as you go is not a real option, since revenue or product schedule or both may be adversely impacted.
Fine pitch, BGA, CSP, 0402, 0201, 01005, thin PCBs and, no-clean flux compound the yield problems
36. Design to Improve ManufacturingFirst Pass Yield Must understand the interdependency of design, incoming materials and manufacturing processes
Then and only then can we achieve higher yield, lower cost and faster time to market
This requires considerable investment of engineering resources at all levels in
a) Process characterization
b) Training not just for ENGINEERS but MANUFACTURING and support staff
37. DFM is one of the key drivers of manufacturing yield
38. DFM is one of the key drivers of manufacturing yield
Very few circuit & board designers have a good understanding of manufacturing
39. DFM is one of the key drivers of manufacturing yield
Very few circuit & board designers have a good understanding of manufacturing
So it is common to blame manufacturing for all the yield problems since that is where defects are discovered
40. Incoming Materials Quality Garbage in = garbage out
There is no way to improve manufacturing yield if
Boards and components have poor solderability
Paste is susceptible to slumping & solder balling
Flux is not compatible with the process, boards or components
Purchasing are unaware of the requirements of the above issues.
Must communicate clearly with suppliers on specific process requirements.
Remember: Industry standards are not procurement specs
Demand materials meet your requirements for which you are paying.
41. Manufacturing Processes & Equipment Once the problems in design and incoming materials have been addressed, it is time to focus on the manufacturing processes and equipment to improve yield and expenses
How should one go about identifying the key manufacturing process issues?
First characterize the process
Document the details of equipment and non-equipment dependent variables that control yield. This document serves as the process recipe
Ensure staff are properly trained and competent on the use equipment
42. ISO 9000 and Quality Most companies claim to have process recipe since most of them are now ISO certified
Unfortunately most ISO 9000 documents do not even come close to defining what variables are important for yield
ISO certification is a good thing but very often it is more of a marketing tool and not very helpful for building products with high yield
ISO requirement: say what you do and do what you say as a result most companies dont say much!
Need detailed recipe to produce quality product
43. Meeting ISO but not Quality Requirements Use one profile for all products. This is OK for ISO but you really need a unique profile for each product
Even an unique profile is not going to help if cause is
Poor solder paste
Mis-registration or misplacement of components
Poor handling of components and boards
The process document needs to address all these issues in specific detail, even though this is more than required for ISO certification
44. Training & Documentation Having the right design, good quality incoming materials and an in-house process document are necessary but not sufficient to achieve high yield on a consistent basis
Training of personnel at all levels, from senior managers to engineers, operators and support staff (i.e. purchasing) is critical for addressing all the issues needed to improve yield and then profitability
45. Quality Assessment Process control is a way of life
Use of statistics and process control
Documented expectation and implementation
Sampling plans for best practice criteria
Keep operators involved in the process
Develop meaningful design of experiments
46. SMT Materials & Process Specification *
SMT Design For Manufacturability (DFM)*
Surface Mount Equipment Characterization (IPC-9850-Not released yet)
SMT Land Pattern Specification (IPC - 782)
Adhesive Specification (IPC - 817)
Solderability Specification (ANSI/J-Std .002/003)
* Need to be developed in-house
47. Solder Fluxes (J-Std -004)
Solder Paste Specification (J-Std -005)
Stencil Design Guidelines (IPC 7525)
Guidelines for Temperature Profiling (IPC-7530)
Component Handling Series IPC-M-109 (Includes J-STD-020/33/35; and IPC-9501/02/03). Formerly IPC-786
SMT Workmanship Standard (J-Std 001/IPC-A- 610)
48. Our thanks go to IPC for providingthe base material forthis presentation