IPC-2221B-2012-最新版本，印制板通用设计标准，2012版本SINGLE USER LICENSE-NOT FOR USE ONA NETWORK OR ONLINEIPGIPC-2221BGeneric Standard onPrinted Board DesignDeveloped by the iPC-2221 Task Group(D-31b)of the Rigid PrintedBoard Committee(D-30)of IPCSupersedes.Users of this publication are encouraged to participate in thePC-2221A-May2003development of future revisionsIPC-2221- February 1998ContactIPC3000 Lakeside Drive, Suite 309SBannockburn Illinois60015-1249Tel847615.7100FaX847615.7105SINGLE USER LICENSE-NOT FOR USE ONA NETWORK OR ONLINEHIERARCHY OF IPC DESIGN SPECIFICATIONS(2220 SERIES)PC2221GENERIC DESIGNPC-2222PC2223PC-2225Pc-2226RIGIDFLEXMCM-LHDIFOREWORDThis standard is intended to provide information on the generic requirements for organic printed board design. All aspectsand details of the design requirements are addressed to the extent that they can be applied to the broad spectrum of thosedesigns that use organic materials or organic materials in combination with inorganic materials(metal, glass, ceramic, etc.to provide the structure for mounting and interconnecting electronic, electromechanical, and mechanical components. It iscrucial that a decision pertaining to the choice of product types be made as early as possible. Once a component mountingand interconnecting technology has been selected the user should obtain the sectional document that provides the specificfocus on the chosen technologyIt may be more effective to consider alternative printed board construction types for the product being designed. As anexample the application of a rigid-flex printed wiring board may be more cost or performance effective than using multipleprinted wiring boards, connectors and cablesIPCs documentation strategy is to provide distinct documents that focus on specific aspect of electronic packaging issuesIn this regard document sets are used to provide the total information related to a particular electronic packaging topic. Adocunent set is identified by a four digit number that ends in zero(O)Included in the set is the generic information which is contained in the first document of the set and identified by the fourdigit set number. The generic standard is supplemented by one or many sectional documents each of which provide specificfocus on one aspect of the topic or the technology selected. The user needs, as a minimum, the generic design document,the sectional of the chosen technology, and the engineering description of the final productAs technology changes specific focus standards will be updated, or new focus standards added to the document set. The IPCinvites input on the effectiveness of the documentation and encourages user response through completion of"Suggestionsfor Improvement"forms located at the end of each documentSINGLE USER LICENSE- NOT FOR USE ON A NETWORK OR ONLINENovember 2012PC-2221BAcknowledgmentAny document involving a complex technology draws material from a vast number of sources. While the principal membersof the IPC-2221 Task Group(D-31b) of the Rigid Printed Board Committee(D-30) are shown below, it is not possible toinclude all of those who assisted in the evolution of this Standard. To each of them the members of the ipc extend theirgratitudeRigid Printed BoardPc22212222Technical liaison of theCommitteeTask GroupIPC Board of directorsChairChairVicka whiteGary ferrariDongkai ShangguanHoneywell AerospaceFTG CircuitsFlextronics internationalVice-ChairⅤice- ChairShane whitesideDebora obitzCliff maddoxTTM TechnologiesTrace-Laboratories- BaltimoreBoeing CompanyIPC-2221 Task GroupAlisha a. amar. Lockheed martinMark finstad, Flexible CircuitDebora l. obit. traceSpace Systems CompanyTechnologies, IncLaboratories baltimoreLance A. Auer, Raytheon MissileLarry F. Foster, Lockheed MartinGerard O Brien, SolderabilitySystemsMissiles fire controTesting solutions IncRobert F bagsby. Rock well CollinsLionel fullwood. WKKJack C. Olson, Caterpillar IncJohn a. bauer. Rockwell collinsDistribution ltdWilliam a. ortloff. raytheonWendi Boger, Viasystems Group, Inc.Mahendra s Gandhi, NorthropCompanyGrumman Aerospace SystemsGerald Leslie bogert, BechtelStephen g. Pierce, SGPPlant Machinery, IncTom Gardenour, AmphenolVentures. IncPrinted Circuits. IncScott a. bowles. L-3 Fuzing andRandy r. reed, ViasystemsMichael r. green Lockheed martinOrdnance SystemsGroup, Incpace systems companySteven A. Bowles, ViasystemsJose a. rios, endicott interconnectPhilip M. Henault, RaytheonGroup, IncTechnologies IncCompanMark buechner. BAE SystemsJoseph e. Kane, bae SystemsJoseph schmidt, Raytheon missileByron Case, L-3 CommunicationsPlatform SolutionsSystemsCalette Chamness, U.S. ArmyJeff Lewis, Holaday Circuits IncDouglas r. Schueller, AbelConnAviation missile commandLLCAnne lomonte. draeger medicalDenise Chevalier, AmphenolSystems, IncGilbert Shelby, Raytheon SystemsPrinted circuits. IncChris mahanna. RobisanCompanyChristine coapman delphiLaboratory IncRobert sheldon pioneerElectronics and safetyKenneth J. Manning, RaytheonCircuits incDavid J. Corbett, Defense SupplyCompRussell S. Shepherd, MicrotekCenter ColumbusKaren E. McConnell, NorthropLaboratoriesWilliam C. Dieffenbacher. BAEGrumman CorporationLowell Sherman, Defense SupplySystems Platform SolutionsPeter Menuez. L-3 CommunicationsCenter columbusC. Don Dupriest, Lockheed MartinCincinnati electronicsValerie A. st. Cyr, Teradyne IncMissiles fire controlRoger J. Miedico, RaytheonBradley Toone, L-3 CommunicationsCPatricia s. Dupuis, RaytheonompanyCrystal E. Vanderpan, UL LLCCompanyGeorge Milad, UyemuraJuan Vasquez, Viasystems Group, IncInternational CorpTheodore Edwards, Dynaco CorpVicka White, Honeywell AerospaceMichael P. Miller. NswC craneTimothy A. Estes, ConductorDewey whittaker, honey wellSteven m. nolan. Lockheed martinAnalysis technologies. IncMaritime systems sensorsAerospaceSINGLE USER LICENSE-NOT FOR USE ONA NETWORK OR ONLINEIPC-2221BNovember 2012This Page Intentionally Left BlankSINGLE USER LICENSE-NOT FOR USE ONA NETWORK OR ONLINENovember 2012PC-2221BTable of contents1 SCOPE4 MATERIALS21Purpose1Materialselectionwwwwwwwwwww.2l1.2Documentation hierarch4.1.1 Material Selection for Structural Strength21PresentationI 4.1.2 Material Selection for Electrical Properties . ...211. 3.1 Dimensional units4.1.3 Material Selection for environmental14Properties21Definition of terms4.2 Dielectric Base Materials (IncludinPrepregs and Adhesives)211. 5.1 Microvia4.2.1 Preimpregnated Bonding Layer(Prepreg)...221.6 Classification of prodt4.2.2 Adhesives………21.6.1 Printed Board Type·4.2.3 Adhesive Films or sheets ........... 241. 6.2 Performance Classification+““““4.2.4 Electrically Conductive Adhesives241.6.3 Producibility Level24.2.5 Thermally Conductive/Electricall1.7Revision level ChangesInsulating Adhesives……….242 APPLICABLE DOCUMENTS4.3Laminate materials252.1IPC4.3.1 High Tg LaminatesJoint Industry Standards…...….….……,44.3.2 Color Pigmentation.......... 252.3 Society of Automotive Engineers ..........5 4.3.3 Dielectric Thickness/SpacingAmerican Society for Testing and Materials..54.3.4 Thermally Conductive Laminates2.5Underwriters labs4.3.5 Minimum Base Material Thickness for2.6PC Card Form Factors .w... 26IEEE4.4262.ANSI∴….5Conductive materials2.8 ANSIESD4.4.1 Electroless Copper Plating ...... 292.9 PCMCIA4.4.2 Semiconductive Coatings……294.4.3 Electrolytic Copper Plating3 GENERAL REQUIREMENTS ..................................644.4 Gold plating…3.1Information hierarch4.4.5 Immersion Silver .............................................31Order of precede4.4.6 Immersion Tin3.1.2 End-Product Performance Requirements4.4.7 Organic Solderability Preservative(OSP)..323.2Design considerations. .....................................84.4.8 Nickel plating3.3Schematic/logic Diagram . ................................93.4Density evaluation4.4.9 Tin/Lead Plating ......3.5Parts list44.l0 Solder coating………………………33Test Requirement Considerations………,…,10Other Metallic Coatings for Edge Printed3.6Board Contacts343.6.1 Electrical104. 4. 12 Metallic Foil/Film . .........................................343.6.2 Printed Board Assembly Testabilit124.5Electronic Component materials363. 6.3 Boundary scan testing134.5.1 Embedded(Buried) Resistors .... 363.6.4 Functional Test Concern for Printed boardAssemblies4.52上 mbedded( Buried) Capacitors…3.6.5 In-Circuit Test concerns for printed board4.5.3 Embedded (Buried Inductorsassemblies154.6Organic Protective Coatings363.6.6 Mechanical.174.6.1 Solder Mask Coatings36Layout evaluation174.6.2 Conformal Coatings3.7.1 Printed Board Layout Design17 4.6.3 Tarnish Protective Coatings3.7.2 Feasibi lity Density evaluation184.7Marking and Legend38SINGLE USER LICENSE-NOT FOR USE ONA NETWORK OR ONLINEIPC-2221BNovember 20124.7.1 ESD Considerations96.4Impedance Controls5 MECHANICAL/PHYSICAL PROPERTIES .............396.4.1 Microstrip5.1 Fabrication Considerations6.4.2 Embedded Microstrip.605.1.1 Bare Printed board Fabrication . .....................396 4.3 Stripline Properties..612 Product/Printed Board Configuration…….396.4.4 Asymmetric Stripline Properties615.2.1 Printed Board Type6.4.5 Capacitance Considerations.... 625.2.2 Printed Board size6.4.6 Inductance Considerations635.2.3 Printed Board Geometries(Size and Shape)7 THERMAL MANAGEMENT5.2. 4 Bow and Twist着着427.1Cooling mechanisms655.2.5 Structural Strength.427.1. Conduction655.2.6 Composite(Constraining-Core) Printed7.1.2 Radiation ..Boards427.1.3 Convection665.2.7 Vibration Design437.1.4 Altitude effects5.3Assembly requirements447.2 Heat Dissipation Considerations5.3.1 Mechanical Hardware Attachment447.2.1 Printed board housings……….665.3.2 Part Support447.2.2 Individual Component Heat Dissipation...675.3.3 Assembly and Test457.2.3 Thermal Management Considerations for5.3.4 Tooling rails for Pc Card Form FactorPrinted board heatsinks67Printed boards……4572.4 Assembly of Heatsinks to Printed Boards…68Dimensioning systems457.2.5 Special Design Considerations for SMT4.1 Dimensions and tolerances45Printed board heatsinks695.4.2 Component and Feature Location.......457.3 Heat Transfer Techniques……5.4.3 Datum Features7.3.1 Coefficient of Thermal Expansion (Cte)Characteristics705.5 Printed Board Thickness Tolerance ...... 497. 3. 2 Thermal Transfer ..w... 705.6 Panelization197.3.3 Thermal Matching705.7Palletization7.4 Thermal Design Reliability706 ELECTRICAL PROPERTIES8 COMPONENT AND ASSEMBLY ISSUES72Electrical Considerations8.1General Placement Requirements736.1.1 Electrical Performance . ...........................538.1.1 Automatic assembl6.1.2 Power Distribution Considerations . ...........538.1.2 Component Placement736.1.3 Circuit Type Considerations538.13 Orientation.746.2 Conductive Material Requirements……568.1. 4 Accessibility.........................756.3Electrical Clearance568.1.5 Design Envelope...756.3.1 B1-Internal Conductors8. 1.6 Component Body Centering.....756.3.2 B2-External Conductors. Uncoated. Sea8.1.7 Flush Mounting Over Conductive Areas....75Level to 3050 m [10,007 feet].8.1.8 Clearances766.3. 3 B3-External Conductors. Uncoated. Over3050m[10,07fet]8.1.9 Physical Support…………………………….768.1.10 Heat Dissipation786.3.4 B4-External Conductors, with permanentPolymer Coating( Any Elevation)………8.1.11 Stress relief786.3.5 A5-External Conductors with Conformal8.2 General Attachment Requirements7Coating over Assembly(Any Elevation).58 8.2.1 Through-Hole796.3.6 A6-External Component Lead/Termination,Uncoated. Sea level to 3050 m8.2.2 Surface Mounting[10,007 feet].....588.2.3Mixed Assemblies...6.3.7 A7-External Component Lead/Termination,8.2.4 Soldering Considerations..80with Conformal Coating(Any Elevation)8 8.2.5 Connectors and interconnects81SINGLE USER LICENSE-NOT FOR USE ONA NETWORK OR ONLINENovember 2012PC-2221B8.2.6 Fastening Hardware83 10 GENERAL CIRCUIT FEATURE8.2.7 StiffenersREQUIREMENTS.1028.2.8 Lands for flattened round leads10.1 Conductor Characteristics8.2.9 Solder terminals10.1.1 Conductor width and Thickness1058.2.10 Eyelets8610.1.2 Electrical clearance1058.2.11 Special Wiring8610.1.3 Conductor routing…………8.2.12 Heat shrinkable devices10.1.4 Conductor Spacing8.2.13 Bus bar.8710.1.5 Plating Thieves…………….………….,1068.2.14 Flexible cable10.2 Land characteristics10.2.1 Manufacturing allowances106Through-Hole requirements8.3. 1 Leads Mounted in Through-Holes1068710.2.2 Lands for Surface mounting10.2.3 Test points1068.4Standard surface mount requirements8.4.1 Surface-Mounted Leaded Components10.24 Orientation Symbols……,1068.4.2 Flat-Pack Components.9210.3 Large Conductive Areas……………………,108.4.3 Ribbon Lead Termination9211 DOCUMENTATION1068. 4. 4 Round Lead termination11.1 Special Tooling.l088.4.5 Component Lead Sockets2IL2Layout8.5Fine Pitch SMT(Peripherals)931 1. 2.1 Viewing1088.6Bare die11.2.2 Accuracy and scale8.6.1 Wire bond11.2.3 Layout Notes8.6.2 Flip Chip∴9311.2.4 Automated- Layout Techniques……,10863 Chip scale…93 11.3 Deviation Requirements1088.7 Tape Automated Bonding………….9311. 4 Phototool Considerations1098.8 Grid Array smt·““··“9311.4.1 Artwork Master Files ....................................1098.9No-Lead Devices ............................................9411. 4.2 Film Base material1098.9.1 Small Outline and Quad Flat No Lead with11.4.3 Solder Mask Coating Phototools ..................109Pullback leads(PQFN,PSON)…………948.10 Compliant Pin Design Guidelines……..9512 QUALITY ASSURANCE12.1 Conformance Test Coupons9 HOLESIINTERCONNECTIONS9512.2 Material Quality assuranceL109.1General Requirements for Lands with Holes.9512.2.1 Laminates9.1.1 Land Requirements512.2.2 Compliant Pin…9.1.2 Annular Ring Requirements9612.3 Conformance evaluations9.1.3 Thermal Relief in Conductor Planes ...............9712.3.1 Coupon Quantity and Location..1109.1.4 Lands for Flattened Round Leads.......97l149.212.3.2 Coupon IdentificationHoles989.2.1 Unsupported Holes12.3.3 General Coupon Requirements1149.2.2 Plated holes9812.4 Individual Coupon Design1149.2.3 Location10012.4.1 Plated Hole Evaluation(Thermal StressRework simulation, Registration) Coupons . 1149.2. Hole pattern Variation10012.4.2 Moisture and insulation resistance9.2.5 Location Tolerances100canonsl159.2.6 Quantity…………………10112.4.3 Hole Solderability Coupons1159.2.7 Spacing of Adjacent Holes………………10112.4.4 Surface Mount Solderability Coupons ...........1159.2.8 Aspect Ratio10112. 4.5 Interconnect resistance and continuity93Via protection10lCouponsl159.3.1 Via Protection Requirements10112.4.6 Solder Mask Adhesion Coupons..1159.3.2 Via fill10l12.4.7 Surface Insulation Resistance Coupons115SINGLE USER LICENSE-NOT FOR USE ONA NETWORK OR ONLINEPc-2221BNovember 201212. 4.8 Peel Strength and Plating AdhesionFigure 5-11 Fiducial Clearance Requirements1116Figure 5-12 Printed Board Panelization/12.4.9 Controlled Impedance Coupons116Palletization, mm12.4.10 Optional legacy Registration Coupons .........116Figure 5-13 Example of Connector Key SlotLocation and tolerance,mm[in]∴…….5212.4.11 Legacy N Coupon(Peel Strength, SurfaceMount Bond Strength -Optional for SMT).116Figure 6-1 Voltage/Ground Distribution Concepts...5412.4. 12 Coupon X(Bending Flexibility andFigure62 Single Reference Edge Routing…….5Endurance, Flexible Printed Board)......116Figure 6-3 Circuit Distribution12.4.13 Process Control Test CouponFigure 6-4 Transmission Line Printed BoardAPPENDIX A.117Figure 6-5 Capacitance VS Conductor Width andDielectric Thickness for Microstrip Lines,APPENDIX B4··,,·162Figure 6-6 Capacitance Vs. Conductor Width andAPPENDIX CSpacing for Striplines, mm [in]64FiguresFigure 6-7 Single Conductor CrossoverFigure 7-1 Component Clearance Requirements forFiqure 1-1Microvia definitionAutomatic Component InsertionFigure 3-1 Package Size and I/O CountFiqure 7-2Relative Coefficient of Thermal ExpansionFigure 3-2 Test Land Free Area for Parts and Other(GTE) Comparison…71intrusions…….16Figure 8-1 Component Orientation for BoundariesFigure 3-3 Test Land Free Area for Tall Partsand/or Wave Solder Applications75Figure 3-4 Probing Test Lands16Figure 8-2 Component Body Centering75Figure 3-5 Example of Usable Area Calculation, mm [inFigure 8-3 Axial-Leaded Companent Mounted Over(Usable area determination includes clearanceConductors76allowance for edge printed board connectorFigure 8-4 Uncoated board clearance76area, printed board guides, and printedboard extracto:)……Figure 8-5 Clamp-Mounted Axial-Leaded Component.76Figure 3-6 Printed Board Density EvaluationFigure 8-6 Adhesive-Bonded Axial-Leaded20Component76Figure 4-1HASL Surface Topology comparison34Figure 8-7 Example of Filleting Compared to Bonding.77Figure 5-1 Example of Printed Board SizeStandardization, mm [ in]41Figure 8-8 Mounting with Feet or StandoffsFigure 8-9 Heat Dissipation examples78Figure 5-2 Typical Asymmetrical Constraining-CoreConfiguration………43Figure 8-10 Lead Bends79Figure 5-3a Multilayer Metal Core Printed Board withFigure8-11 Typical Lead Configurations……79TWo Symmetrical Copper-Invar-CopperFigure8-12 Typical Keying Arrangement……82Constraining Cores(when the Copper.Invar-Copper planes are connected toFigure 8-13 Printed Board Edge Tolerancingthe plated-through hole, use thermalFigure 8-14 Lead-In Chamfer Contiguration,.relief per Figure 9-4)Figure 5-3B Symmetrical Constraining Core PrintedFigure 8-15 TWo-Part Connector83Board with a Copper-Invar-CopperFigure 8-16 Edge-Board Adapter ConnectorCenter Core.43Figure 8-17 Round or Flattened(Coined) Lead JointFigure 5-4 Advantages of Positional Tolerance OverDescriptionBilateral Tolerance, mm [in]Figure 8-18 Standoff Terminal Mounting, mm [in]85Figure 5-5 Datum Reference Frame47Figure 8-19 Dual Hole Configuration for InterfacialFigure 5-6 Example of Location of a Pattern ofand Interlayer Terminal Mountings..... 86PTHs,mm[in]…Figure 8-20 Partially Clinched Through-Hole Leads .......88Figure 5-7 EXample of a Pattern of Tooling/MountingFigure 8-21 Dual In-Line Package(DIP)Lead BendsHoes,mm[i」Figure 8-22 Solder in the Lead Bend Radius88Figure 5-8 Example of Location of a Conductor PatternUsing Fiducials, mm [in]Figure 8-23 TWO-Lead Radial-Leaded components....89Figure 5-9 Example of Printed Board Profile LocationFigure 8-24 Radial Two-Lead Componentand Tolerance, mm [ir50Mounting, mm [in]89Figure 5-10 Example of a Printed Board DrawingFigure 8-25 Meniscus Clearance, mm [in]89Utilizing geometric Dimensioning andFigure826“o” Can Radial- eaded ComponentTolerancing, mm [in]mm [in]