Terms related to flexible PCB boards and electronIC circuit boards
Bending PCB is mainly used in many products, such as mobile phones, laptops, PDAs, digital CAMeras, LCMs, etc The following is an introduction to common terms related to FPC
1.. Access Hole (through hole, bottom hole)
After refers to the protective layer mask on the surface of the flexible board (the performance hole that must be pushed out first) However, it is necessary to intentionally expose holes, rings, hole walls or square pads required for welding in order to weld parts The so-calLED "manhole" in the original text refers to a hole on the surface, which enables the outside world to "approach" the solder joint on the circuit board under the surface sheath Some multilayer boards also have such exposed holes
2.. Acrylic
It is a common name for polyacrylic resin
3.. Adhesive glue or adhesive
Substances, such as resin or paint, can make two interfaces connect
4.. Anchoring Spurs
On the middle board or single board, some fingers can be added to the extra space outside the hole ring to make the hole ring more powerful, in order to make the hole ring gasket have stronger adhesion on the board surface Merge to reduce floating opportunities
Bandage and bending ability
As a characteristic of Dynamic Flex Board, such as the flexible Board connected to the print head of the computer magnetic disk driver, its quality should reach 1 billion "bending test"
6.. Bonding Layer
After refers to the film layer of the Multi layer board, or the adhesive layer between the copper skin and the polyimide (PI) substitute
7. Coverlay/protective layer
For the outer layer of the soft board, solder mask is not easy to use. It is used as a green paint for hard boards because it may fall off when bent It is necessary to use a soft "acrylic" layer to laminate the surface of the circuit board, which can be used as a soldering mask and protect the external circuit to improve the durability and durability of the soft board "Outer film" refers specifically to the outer layer or protective layer
8.. Dynamic Flex (FPC) dynamic soft board
Referers to the Flexible circuit board that needs to be used for continuous motion, such as the flexible circuit board in the read/write head of the magnetic disk driver In addition, there is another "Static FPC" (Static FPC), which refers to the type of FPC that will not move after correct assembly
9. Film adhesive, then film, adhesive film
It refers to the adhesive layer of dry laying, which can be a film containing reinforced fiber cloth, or a thin layer without reinforcement information and only adhesive information, such as the adhesive layer of FPC
10. FPC soft board
It is a special circuit board that can be changed in three-dimensional space during downstream assembly, and its substrate is flexible polyimide (PI) or polyester (PE). This flexible plate, like a hard plate, can be made of electroplated through-hole or surface mounting pads for through-hole mounting or surface mounting The surface of the circuit board can also be attached with a soft covering layer for protection and solder blocking, or printed with green paint masked with soft solder
11. Flexural Failure flexural damage
The material (plate) is broken or damaged due to repeated bending and bending actions
12. Kapton polyimide soft material
This is the trade name of DuPont's products. It is a kind of "polyimide" sheet insulation soft material It can be made into the base material of flexible board (FPC)
13. Membrane Switch membrane switch
Using the transparent polymer (Mylar) film as the carrier, the silver paste (SilverPastes or silver paste) is printed on the thick film circuit by the screen printing method, and then matching the middle space spacer with the protruding panel, or PCB Combined, it becomes a "tactile" switch or keyboard This SMAll "button" device is usually used to hold small abacus, electronic dictionary, and remote control of some household appliances, It is called "membrane switch"
14. Polyester Films polyester sheet
PET flakes for short, usually called MylarFilms, is a DuPont product with good resistance In the circuit board industry, the transparent protective layer on the surface of the imaging dry film and the overlay on the surface of the flexible board (FPC) are all PET films, and they can also be used as the substitute for silver paste printed film circuits (MembraneCircuit) In the electronic industry, it can also be used as the insulation layer of cables, transformers, coils, or as tubular storage equipment for multiple ICs
15. Polyimide (PI) Polyimide
It is an excellent resin that is co-polymerized by Bismaleimide and Aromaticdiamine. It is called Kerimid 601, a powdered resin product launched by France's "Rhone Planck" company DuPont made it into a piece of paper called Kapton This PI board has excellent heat resistance and resistance It is an important raw material for flexible board (FPC) and tape automatic bonding (TAB) Its translation name is "Polyacrylamide"
16. Reel to reel (reel) linkage operation
Some electronIC parts and components can be produced by the riel (riel) retractable process, such as TAB, IC lead frame, some flexible boards (FPC), etc, Tape can be used to recover and wind, facilitating online automatic operation, saving time and labor cost for single piece operation PCB