large area conductor connection leg processing
In a large area of the ground (electricity), commonly used components of the legs connected to the connection leg processing needs to be considered in terms of electrical performance, the component legs of the pad and copper surface is better, but the Components of the welding assembly there are some bad risks such as:
① welding need high-power heater.
② easy to cause the virtual solder joints.
So taking into account the electrical performance and process needs, made of cross-pad, known as the heat shield (heat shield) commonly known as the thermal pad (Thermal), so that the welding can be too much heat due to cross-section of the potential Greatly reduced. Multilayer board of the power (ground) layer of the same treatment.
the role of routing network system
In many CAD systems, cabling is determined by the network system. The grid is too dense, although the channel has increased, but the pace is too small, the figure of the amount of data is too large, which is bound to the equipment storage space has a higher demand, but also the object computer class electronic computing speed Great influence. And some passages are ineffective, such as those occupied by the pads of the component legs or by the holes, which are occupied by the holes. The grid is too sparse, the passage of too little impact on the cloth rate. So there must be a dense and reasonable grid system to support the wiring.
The distance between the legs of the standard component is 0.1 inch (2.54 mm), so the foundation of the grid system is generally set to an integer multiple of 0.1 inch (2.54 mm) or less than 0.1 inch, such as 0.05 inch, 0.025 inch, 0.02 Inch and so on.