The diagram shows a sectional view of the fourth floor board. Usually on circuit boards, components are placed at the top level, regarding Canada's layout of the printed circuit board assembly industry chain. The schematic diagram is shown in Figure 1.
Nowadays, printed circuit board assembly often match them and cannot achieve high accuracy and reliability.
However, due to the fact that the necessary connections or wire lengths when applied to printed circuit board assembly components must be very short, the assembly line under the grid must be minimized as much as possible.
Although the selection of production lines for connecting the leads required for several welding bridges is limited, there are regulations for X-ray scanning and welding, BGA, device termination, and other aspects. The person considering it may also understand and be familiar with the knowledge through.
The complex lead frame assembled on one side is a fast fixed device with characteristics of reliability, balance, and direct operation. Flexible and interconnected process requirements are required between lead frames that cannot be used on PCB boards. The fixed position of mounting a printed circuit board on the surface can be adjusted by applying an external deformation to form a "lead". The lead substrate of resistive components is usually printed with thick film silk screen. General metal wires are sintered using silver palladium powder and alkali free copper powder layers. But for wave soldering, silver palladium phenol is printed on the substrate, and then the coating is printed using silver powder polyester mesh. The tin wire is thin and straight. When soldering, some probes should be added or touched with a soldering iron to see if it has been scraped off. This is mainly due to the fact that the chip pins of the tin bead have not been wet, blackened, or formed by blackening. So, it must be used and glued before the problem can be solved.

Turn on the machine and clean the components on the soldering pad with a soldering iron. Be careful not to use excessive force to prevent damage to the components.
Use tweezers again to clamp the components and scrape off the rosin oxide on the PCB board with alcohol. At this time, use a soldering iron to warm and dry it appropriately.
Wait for the welding to be completed, heat it with an electric soldering iron, and then use flux to stick the iron shell onto the soldering iron frame. Wait for the flux to melt before welding. Weld PCB and wire with flux in the shortest possible time. To avoid oxidation, it is necessary to connect the welding wire to FK after welding and clean the oxide on the soldering iron head to avoid additional stress caused by welding, causing discoloration of the paint surface or silver paste at the solder joint.
To prevent oxidation, even if reliable methods are used, it is best not to use welding processes. However, sometimes due to high electrical resistivity, the fatigue of low-temperature welding rods is not high, making it difficult to put forward new requirements for circuit board design because they have certain temperature limitations, which may exceed the specifications of the circuit board.
It is best to maintain communication with the design engineer for the design of the circuit board, not to sacrifice development time, but to maintain the flexibility of the circuit board design.

The main factors that need to be noted in offline programming are the parameters on the circuit board, flying needle parameters, and the device packaging form of SOP packaging.