circuit board assembly in China
7, fly line - has two meanings
Automatic routing, with the similar observation when the rubber band for a network connection, the table transferred across the network components and do a preliminary layout, with the "Show command, you can see the layout of the network connection of the cross-state, and adjustments component position to make this cross at least, to get the maximum rate of auto-routing fabric through this step is very important, can be said that may quicken power, more time, value! In addition, the automatic routing end, also What network is not Bouton, also available through this function to find. find no Bouton network, can be manually compensated, compensation is not necessary to use "flying line" of the second layer of meaning, is the future of the printed board connected with a wire on these networks. To explain, if the board is high-volume automated production line, fly line can be regarded as 0 in Europe this resistance, the resistance of a uniform pad pitch for design elements. printed circuit board (Printed circuit board assembly, PCB) will appear in almost every electronic device which, if in a kind of electronic device parts, they are also set in various sizes on the PCB in addition to a variety of small parts is fixed, PCB's main function is to provide top of the parts of each electrical connection with electronic devices become increasingly complex, requiring more and more parts, PCB and components on top of the line more and more dense. standard PCB looks like this. bare board (no top part) is also often referred to as "PCB Printed Wiring Board (PWB)". The board itself is insulated substrate is not easy to bend the material into the production. Can be seen on the surface of the small line material is copper, copper foil is covered in the original board, and in the manufacturing process was partially etching away, leaving to become part of a network of fine lines. These lines are called conductors (conductor pattern) or said wiring, and components used to provide circuit connections on the PCB. Fixed to the part above the PCB, we will pin them directly soldered wiring. At the most basic PCB (single panel), the parts are concentrated in one side, wire is focused on the other side. Way we need holes in the board, so the pin can pass through the board to the other side, so part of the pin is welded on the other surface. Because of this, PCB's were called positive and negative parts surface (Component Side) and the welding surface (Solder Side). If the PCB on top of some parts, need to be removed after completion of production or putting it back, then the parts will be used when installing socket (Socket). As the jack is soldered directly on the board, removable parts can be arbitrary. See below is the ZIF (Zero Insertion Force, dial zero insertion force) receptacles, which allows parts (in this case is the CPU) can be easily inserted into the socket, also can be removed. Socket next to the lever, in your part will be inserted into its fixed. If you want two PCB interconnected, generally we will use commonly known as "Goldfinger" edge connectors (edge ??connector). Goldfinger contains many of the bare copper pad, the copper pad is in fact part of PCB layout. Normally connected, we will be one of a finger on the PCB on the PCB inserted into another piece of the appropriate slot (generally called a slot Slot). In a computer, such as video card, sound card or other similar interface cards are connected by the finger to the motherboard. Green or brown on the PCB, the solder mask paint (solder mask) color. This layer is the insulating layer of protection can protect the copper, it can not prevent the parts being welded to the right place. Also in the solder layer will be printed on the surface layer of screen printing (silk screen). Usually this will be printed above the text and symbols on the (mostly white), to mark out the parts in position on the board. Screen printing is also called icon surface area (legend). Edit this paragraph the main PCB design process
In PCB design, in fact, before the formal route, but also after a very long step, the following is the main PCB design process:
First you have to plan out all the electronic equipment system specifications. Contains the system functions, cost limits, size, operating conditions and so on.
System function block diagram
Next we must create a system block diagram. The relationship between box must also be marked. The system will be split several PCB system partition number of the PCB assembly, not only in size can be reduced, but also allows the system has the ability to upgrade and swap parts. System function block diagram provides a basis for our division. Like a computer can be divided into motherboards, graphics cards, sound cards, floppy drives and power supplies and so on. Decided to use the encapsulation method, and the size of the PCB when the PCB technology used and the number of circuits have decided well, next step is to determine the size of the board. If the PCB design is too large, then the packaging will change, or re-action for partition. In the choice of technology, but also the circuit diagram of the quality and speed into consideration.Listen