FPC soft electronic circuit board related terms

FPC is a flexible electronic circuit board. The flexible circuit board is made of polyimide or polyester film and is a highly reliable and excellent flexible printed circuit board. Known as a soft board or FPC, it has the characteristics of high wiring density, light weight and thin thickness.

FPC is mainly used in mobile phones, laptops, PDAs, digital cameras, LCM and many other products. Here are some common terms related to FPC.

1. The inspection hole exposes the hole (the worn exposed hole, the bottom hole is exposed)

Often referred to as the protective layer of the soft cover overlaylay (the bare hole must be first punched), it is used to bond the surface of the soft board to a solder mask. However, the hole ring wall or square pad required for welding must be intentionally exposed to facilitate the welding of the parts. By "through hole" the original text means that there is a hole on the surface to be exposed so that the outside can "close" the surface of the surface to the surface of the surface of the solder joint. Some multilayer boards also have such exposed holes.

2, acrylic acid acrylic

It is the generic name for polyacrylic resins. Most soft boards use their films as a follow-up film.

3, glue or glue

A substance that allows two interfaces to be combined, such as a resin or paint.

4, anchor the Spurs

In the middle plate or the single plate, in order to make the hole ring pad have stronger adhesion on the surface of the plate, some finger claws may be added in the extra blank space outside the hole ring to make the hole ring stronger to reduce the possibility of springboard. Sex.

5, bendability, bending ability

Functional soft boards of the Dynamic Flex Board (such as the print head of a computer disk drive) should perform a "bend test" of one billion times.

6, bonding layer bonding layer, layer

A film layer commonly referred to as a multilayer board, a sheet of TAB tape or a soft board, that is, an adhesive layer between a copper sheet and a polyimide substrate.

7, Coverlay / Cover Coat overlay, protective layer

The outer layer of the flexible board is not easy to use the green paint used for the hard board because it may fall during the bending process. It is necessary to use a soft "acrylic" laminate on the surface of the board that acts as a solder resist and protects the outer layer and enhances the electrical resistance and durability of the soft board. The outer film is specifically referred to as a cover layer or a protective layer.

8, Dynamic Flex (FPC) dynamic soft board


Refers to a flexible circuit board that requires continuous motion, such as a soft board in a disk drive read/write head. In addition, "static FPC" refers to a soft board that no longer functions after assembly.

9, the film is followed by a film, film

Refers to a dry sheet adhesive layer, which may or may not comprise a thin layer of reinforcing material, but only a binder material, such as an FPC adhesive layer.

10, flexible printed circuit board, FPC soft board

It is a special board that can be used for 3D shape changes when assembled downstream. The substrate is a flexible polyamine (PI) or a polyester (PE). This soft board is also similar to a hard board and can be made of plated through holes or surface pads for through hole insertion or surface bonding. The board surface can also be attached with a soft overlay to provide protection and soldering protection, or a soft solder mask green coating.

11, bending damage

The material (sheet) is broken or damaged due to repeated bending and flexing, which is called bending failure.

12, Kapton polyimide soft material

This is the trade name of DuPont products. It is a "polyimide" sheet-like insulating soft material. After bonding a rolled copper foil or an electroplated copper foil, a soft board (FPC) substrate can be produced. .

13, membrane switch membrane switch

A clear polyester (Mylar) film is used as a carrier, and a silver paste (Silver Pastes or Silver Paste) is printed on a thick film line by a screen printing method, and then combined with a hollowed-out gasket to bond with a convex panel or a PCB. Become a "touch" switch or keyboard. Such small "button" devices, commonly used in handheld calculators, electronic dictionaries, and certain home appliance remotes, are referred to as "membrane switches."

14, Polyester Films polyester sheet

Referred to as PET sheet, the most common is DuPont's product MylarFilms, which is a material with good electrical resistance. In the circuit board industry, the transparent protective layer on the surface of the imaged dry film, and the Coverlay on the surface of the soft board (FPC) are PET film, and it can also be used as the substrate of the silver film circuit (Membrane Circuit). In the electronics industry, it can also be used as a cable, a transformer, an insulating layer of a coil, or a tubular storage device for multiple ICs.

15, Polyimide (PI) polyamine

It is an excellent resin which is polymerized by Bismaleimide and Aromaticdiamine. It was first known as the powdery resin product Kerimid 601 from the French company "Rhone-Poulenc". DuPont made it into a sheet called Kapton. This type of PI sheet is excellent in heat resistance and electrical resistance. It is an important raw material for soft board (FPC) and automatic tape winding (TAB). It is also an important sheet for advanced military hardboard and supercomputer motherboards. The translated name of the mainland is "poly-pyrene."

16, Reel to Reel reel (disc) linkage operation

Some electronic component assemblies can be produced by reeling and reeling processes, such as TAB, IC's Lead Frame, and some soft boards (FPC), which can be retracted by tape. Convenient to complete its online automated work to save time and labor costs for one-piece work.