The test circuits are based on a microstrip transmission line structure with a through-hole in the middle of the circuit used as a conductor and signal transition from the top copper layer of the dielectric substrate material to the bottom copper layer.
For high - level circuit board processing technology research literature, the industry is relatively few. This paper introduces the control points of key production processes, such as material selection, laminated structure design, interlayer alignment, i
Due to the number of high-rise board layers, the customer design end of PCB layer alignment requirements are more and more strict, usually the inter-layer alignment tolerance control ±75μm, considering the large size design of high-rise board units, graph
The surface of the board in machining (drilling, laminating, milling, etc.) process caused by oil or other liquids contaminated with dust pollution surface treatment phenomenon.
Components with large heat or current should not be placed in the corners and edges of PCB board, and radiators should be installed as far as possible, and away from other devices, and ensure that the heat dissipation channel is smooth.
The impedance and loss of PCB are crucial to the transmission of high-speed signals. In order to analyze such a complex transmission channel, we can study its impact on signals through the impact response of transmission channel.
Hot air smoothing is to dip the printed circuit board into the molten solder (63SN/37PB), and then use the hot air to blow off the excess solder on the surface of the printed circuit board and in the metallized hole, to obtain a smooth, uniform and bright
At present, our company through a large number of experiments, choose different types of ink and viscosity, adjust the pressure of screen printing, basically solve the hole hole and uneven, has adopted this process for mass production.
Compared with the dip welding process, the motion of solder solution and PCB board in the drag welding process makes the thermal conversion efficiency better than that in the dip welding process.
The circuit working at high frequency should consider the interference between components. The general circuit should make parallel arrangement of components as far as possible to facilitate wiring;
One end of the triangle is connected to a signal wire and the other is connected to ground. When static electricity is present, a tip discharge is generated which consumes electrical energy.
The intermetallic bonds between copper and tin form grains whose shape and size depend on the duration and strength of the temperature at the time of welding.
Telegram