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1.IC: U * transistor: Q * single resistor: R * OSCILLATOR: OSC * Capacitance: C * SIP Pai: RA * Variable resistance: VR * CRYSTAL: X * Inductance: L * DIP Exclusion: RP * Variable Capacitance: VC * CONNECTOR: J * Battery: BT * JUMPER: JP * SPEAKER: BZ * DIODE ARRAY: DA * FUSE: F * Diode: D * Transfo...

1. The fixed position of the parts, according to the project icon, on the right position, and confirm the direction of foot and foot number. 2. Although the drawings indicate the location, but the non-fixed position of the parts, according to LAYOUT need to be adjusted, and inform the relevant ...

PCB board welding process 1. PCB board welding process 1.1 PCB board welding process introduced PCB board welding process required manual plug-in, manual welding, repair and inspection. 1.2 PCB board welding process Sort components by list - Add-ons - Welding - Cut toe - Check - Tri...

BGA maintenance skills  SUNKKO 852B parameters of the state is set to: temperature 280 ℃ ~ 310 ℃; untwisting time: 15 seconds; Merry flow parameters: × × × (1 ~ 9 files can be preset by the user code);      Finally, the disassembler will be set to automatic mode, SUNK...

BGA component assembly and rework Because PBGA is moisture sensitive, preconditioning should be taken prior to assembly. It is recommended that all packages be fully assembled and reflowed within 24 hours. Excessive removal of the device from the antistatic bag can damage the device. CBGA i...

Silkscreen: Its role is to solder paste or patch glue printed on the PCB pad, in preparation for the welding components. Equipment used for screen printing machine (screen printing machine), located in the forefront of the SMT production line. ???? Dispensing: It is the glue drops to the PCB's fixed...

It is not easy to create and select a surface-mount process that is tailored to the specific product. Because SMT technology involves a number of technical complex systems engineering, any of these factors will affect the quality of the welding of electronic products. ? The soldering quality of comp...

Land, the basic building block for surface-mount assembly, used to make a land pattern of the board, ie, a variety of land combinations designed for specific component types. There is nothing more frustrating than designing poor pad structures. When a pad structure is not properly designed, it is di...

A: The correct use of electric iron 1, electric soldering iron before use on the tin, the specific method is: the electric soldering iron heat until just to melt the solder, coated with flux (rosin), and then evenly coated with solder on the tip, the tip evenly Eat a layer of tin (shiny thin can be)...

Today's SMT products are becoming increasingly complex, with smaller and smaller electronic components, thinner and smaller wires, and rapid development of new components. Following the BGA, CSPs and FCs have also entered a practical phase, making SMA's quality inspection technology more and more co...

1, electric iron more than 3-5 seconds components and printed circuit boards will be damaged, especially the lead-free soldering temperature for a long time more vulnerable to damage, overheating will make the pad failure, will pcb printed surface lines, board Because of overheating bad ? 2, surface...

With the extensive use of efficient welding processes, shipbuilding has become increasingly demanding on welding materials. However, according to many domestic shipbuilding enterprises, the quality of ship welding materials in our country is mixed with different standards and the problems caused by ...

In the circuit board welding process due to improper operation or welding personnel non-professional welders often happen Weld circuit board, then what is Weld it? In fact, it is very simple to explain, the most common saying is that poor contact. How to find out in the shortest time what is the loc...

Patch process is divided into: Solder paste printing, SMT chip (by hand and machine), the middle inspection, reflow soldering, furnace inspection, performance testing, aging test (some do not need), packaging ? 1, printing solder paste. After the solder paste to warm after the first mixing, and then...

Before and after a glue cycle, it is a good idea to drop at least two separate gel spots on the board to represent each point of the diameter. This allows the operator to compare the gel point quality during the recycle cycle. These points can also be used to survey the glue point diameter. Gel poin...

Single-sided fully inserted substrate ? Is the most basic, the most common type, the process of its installation has a long plug and short plug points. Long plug refers to the device pin without pre-processing and directly into the circuit board mounting hole; short plug refers to the components of ...