Qualification and Performance Specification for Flexible Printed Boards
|Publication Date:||1 November 2003|
This specification covers qualification and performance requirements of flexible printed wiring. The flexible printed wiring may be single-sided, double-sided, multilayer, or rigid-flex multilayer. All of these constructions may or may not include stiffeners, plated-through holes, and blind/buried vias.
The purpose of this specification is to provide requirements for qualification and performance of flexible printed wiring designed to IPC-2221 and IPC-2223.
Performance Classification, Wiring Type, and Installation Usage
This specification recognizes that flexible printed wiring will be subject to variations in performance requirements based on end-use. These performance classes (Class 1, Class 2, and Class 3) are defined in IPC-6011.
Performance requirements are established for the different types of flexible printed wiring, classified as follows:
Type 1 Single-sided flexible printed wiring containing one conductive layer, with or without stiffeners.
Type 2 Double-sided flexible printed wiring containing two conductive layers with plated-through holes, with or without stiffeners.
Type 3 Multilayer flexible printed wiring containing three or more conductive layers with plated-through holes, with or without stiffeners.
Type 4 Multilayer rigid and flexible material combinations containing three or more conductive layers with plated-through holes.
Type 5 Flexible or rigid-flex printed wiring containing two or more conductive layers without plated-through holes.
Use A Capable of withstanding flex during installation.
Use B Capable of withstanding continuous flexing for the number of cycles as specified on the procurement documentation.
Use C High temperature environment (over 105 °C [221 °F]).
Use D UL Recognition.
Selection for Procurement
For procurement purposes, performance class and installation usage shall be specified in the procurement documentation.
The documentation shall provide sufficient information to the supplier so that the supplier can fabricate the flexible printed wiring and ensure that the user receives the desired product. Information that should be included in the procurement documentation is shown in IPC-D-325.
The procurement documentation should specify the requirements that can be selected within this specification. However, in the event that these selections are not made in the documentation, the following default selections shall apply:
Performance Class - Class 2
Installation Usage - Use A
Material, Plating Process and Final Finish
Laminate material is identified by numbers and/or letters, classes and types as specified by the appropriate specification listed in the procurement documentation.
The copper plating process used to provide the main conductor in the holes is identified by a single number as follows:
1. Acid copper electroplating only.
2. Pyrophosphate copper electroplating only.
3. Acid and/or pyrophosphate copper electroplating.
The final finish can be but is not limited to one of the designators given below or a combination of several platings and is dependent on assembly processes and end-use. The procurement documentation shall specify finish designators. Unless otherwise specified, thicknesses given in Table 1-1 shall apply.
S Solder Coating (Table 1-1)
T Electrodeposited Tin-Lead (fused) (Table 1-1)
X Either Type S or T (Table 1-1)
TLU Electrodeposited Tin-Lead (unfused) (Table 1-1)
G Gold Electroplate for Edge Board Connectors (Table 1-1)
GS Gold Electroplate for Areas to be Soldered (Table 1-1)
GWB-1 Gold Electroplate for areas to be wire bonded (ultrasonic)
GWB-2 Gold Electroplate for areas to be wire bonded (thermosonic)
N Nickel Electroplate for Edge Board Connectors (Table 1-1)
NB Nickel Electroplate as a Barrier to Copper-Tin Diffusion (Table 1-1)
OSP Organic Solderability Preservative (tarnish and solderability protection during storage and assembly processes) (Table 1-1)
ENIG Electroless Nickel Immersion Gold
IS Immersion Silver
IT Immersion Tin
C Bare Copper (Table 1-1)
''Shall,'' the imperative form of the verb, is used throughout this standard whenever a requirement is intended to express a provision that is mandatory. Deviation from a ''shall'' requirement may be considered if sufficient data is supplied to justify the exception.
The words ''should'' and ''may'' are used whenever it is necessary to express nonmandatory provisions.
''Will'' is used to express a declaration of purpose. To assist the reader, the word ''shall'' is presented in bold characters.
Revision Level Changes
Changes made to this revision of the IPC-6013 are indicated throughout by gray-shading of the relevant subsection(s). Changes to a figure or table are indicated by gray-shading of the figure or table header.