The main reasons for poor wetting are: 1, the surface of the welding area is polluted, 2, when the residual metal in the solder exceeds 0.005%, the activity of the flux is reduced, 3, wave soldering, there is gas on the surface of the substrate,
Analysis of bad causes of PCBA patch processing plant: 1, PCBA air welding, 2, PCBA short circuit, 3, PCBA warping, 4, PCBA missing parts, 5, PCBA tin beads, 6, PCBA offset
The milling technology of circuit board CNC milling machine includes the selection of cutting direction, compensation method, positioning method, frame structure, the next cutter point, which is an important aspect to ensure the milling precision.
Five common silver plating defects of multilayer circuit boards have been solved by solution manufacturers, equipment manufacturers and PCB factories, and some methods have been found to prevent and improve them.
Prevention can be carried out in the following ways: 1, moisture-proof storage of components, 2, choose well-known brand solder paste, 3, adjust printing parameters, 4, adjust reflow temperature curve, 5, try to use reflow welding, reduce manual welding,
The quality control of the whole pcba process is very important. 1.PCB circuit board manufacturing; 2.PCBA incoming components procurement and inspection; 3.SMT patch processing; 4. Plug-in processing, 5. Program burning, 6.PCBA board test
The emptiness is mainly caused by the following reasons: first, welding paste. Two, PCB welding pad surface treatment. Three, reflux curve setting. Four, reflux environment. Five, pad planning. Six, micropores.
To repair and maintain the internal circuit board, the following maintenance methods are: 1, inspection components, 2, welding state analysis, 3, component direction detection, 4, tool inspection of parts, 5, startup test
Analysis of PCB deformation causes :1. The uneven area of the copper plane on the circuit board will aggravate the bending and warping of the circuit board. 2. The weight of the PCB board itself may also cause the board to sag and deform.
Key parameters of reflow welding equipment :1. Number, length and width of temperature zone; 2. Symmetry of upper and lower heaters; 3. Uniformity of temperature distribution in the warm zone; 4. Independence of transmission speed control in temperature i
PCB circuit board four special plating methods: finger plating, through hole plating, coil continuous selection plating, brush plating.
Because the wider the printed line is, the smaller the inductance is, the lead line from the pad to the hole should be widened as far as possible, and the width of the pad should be the same as far as possible. In this way, even the capacitance of 0402 pa
