Why do PCBS now have halogen requirements?
When PCB is used for hot air leveling and component welding, the board is subjected to high temperature (> 200), will also release trace amounts of hydrogen bromide。
When PCB is used for hot air leveling and component welding, the board is subjected to high temperature (> 200), will also release trace amounts of hydrogen bromide。
With the development of large-scale integrated circuit and super-large scale integrated circuit, the multilayer printed board (PCB) will be used more and more.
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;
Too low density of alkaline etching solution will aggravate side erosion, choosing etching solution with high copper concentration is very beneficial to reduce side erosion.
high heat dissipation devices in connection with the substrate should be able to reduce the thermal resistance between them.
To evaluate the heat dissipation capacity of PCB, it is necessary to calculate the equivalent thermal conductivity (9EQ) of the insulating substrate for PCB, which is composed of various materials with different thermal conductivity.
Circuit board system interconnection includes chip to circuit board, PCB board interconnection and signal input/output between PCB and external devices.
In the process of PCB high-speed signal circuit design and wiring, engineers need to shorten the lead between the pins of high-speed circuit devices as much as possible.
In the future, with the emergence of new demands for automotive electronics, data centers and artificial intelligence, PCB industry will usher in new growth points.
Each circuit layer in the multilayer circuit board is pressed together by the action of semi-cured sheet; Depending on the circuit design, some areas of the semi-cured sheet need to be cut and then pressed together.
the environmental problems involved in PCB production are particularly prominent. The topic of lead and bromine is the hottest, lead-free and halogen-free will affect the development of PCB in many ways.
Therefore, careful consideration should be given to the placement of ground wires in the layout. Mixing all kinds of ground will cause unstable power supply. The following points should be noted in the design of ground wire: