Communication Equipment PCB
In order to shorten the signal transmission distance and reduce the signal transmission loss, the 5G communication board.
Step by step to high-density wiring, fine wire spacing,the development direction of micro-aperture, thin type and high reliability.
In-depth optimization of processing technology and manufacturing process of sinks and circuits, surpassing technical barriers.Become an excellent manufacturer of 5G high-end communication PCB board.
Communication Industry And PCB Products
| Communication industry | Main equipment | Required PCB products | PCB feature |
|
Wireless network |
Communication base station |
Backplane, high-speed multilayer board, high-frequency microwave board, multi-function metal substrate |
Metal base, large size, high multilayer, high frequency materials and mixed voltage |
|
Transmission network |
OTN transmission equipment, microwave transmission equipment backplane, high-speed multilayer board, high-frequency microwave board | Backplane, high-speed multilayer board, high-frequency microwave board |
High speed material, large size, high multilayer, high density, back drill, rigid-flex joint, high frequency material and mixed pressure |
| Data communication |
Routers, switches, service / storage Devic |
Backplane, high-speed multilayer board |
High-speed material, large size, high multi-layer, high density, back drill, rigid-flex combination |
| Fixed network broadband |
OLT, ONU and other fiber-to-the-home equipment |
High-speed material, large size, high multi-layer, high density, back drill, rigid-flex combination |
Multilay |
PCB Of Communication Equipment And Mobile Terminal
Communication Equipment
Mobile Terminal
Process Difficulty Of High Frequency And High Speed PCB Board
| Difficult point | Challenges |
| Alignment accuracy | The precision is stricter, and the interlayer alignment requires tolerance convergence. This kind of convergence is more stringent when the size of the plate changes |
| STUB (Impedance discontinuity) | The STUB is stricter, the thickness of the plate is very challenging, and the back drilling technology is needed |
|
Impedance precision |
There is a great challenge to etching: 1. Etching factors: the smaller the better, the etching accuracy tolerance is controlled by + /-1MIL for lineweights of 10mil and below, and + /-10% for linewidth tolerances above 10mil. 2. The requirements of line width, line distance and line thickness are higher. 3. Others: wiring density, signal interlayer interference |
| Increased demand for signal loss | There is a great challenge to the surface treatment of all copper clad laminates; high tolerances are required for PCB thickness, including length, width, thickness, verticality, bow and distortion, etc. |
| The size is getting bigger | The machinability becomes worse, the maneuverability becomes worse, and the blind hole needs to be buried. The cost increases 2. The accuracy of alignment is more difficult |
| The number of layers becomes higher | The characteristics of denser lines and via, larger unit size and thinner dielectric layer, and more stringent requirements for inner space, interlayer alignment, impedance control and reliability |
Accumulated Experience In Manufacturing Communication Board Of HUIHE Circuits
Requirements for high density:
The effect of crosstalk (noise) will decrease with the decrease of linewidth / spacing.
Strict impedance requirements:
Characteristic impedance matching is the most basic requirement of high frequency microwave board. The greater the impedance, that is, the greater the ability to prevent the signal from infiltrating into the dielectric layer, the faster the signal transmission and the smaller the loss.
The precision of transmission line production is required to be high:
The transmission of high-frequency signal is very strict for the characteristic impedance of the printed wire, that is, the manufacturing accuracy of the transmission line generally requires that the edge of the transmission line should be very neat, no burr, notch, nor wire filling.
Machining requirements:
First of all, the material of the high-frequency microwave board is very different from the epoxy glass cloth material of the printed board; secondly, the machining precision of the high-frequency microwave board is much higher than that of the printed board, and the general shape tolerance is ±0.1mm (in the case of high precision, the shape tolerance is ±0.05mm).
Mixed pressure:
The mixed use of high-frequency substrate (PTFE class) and high-speed substrate (PPE class) makes the high-frequency high-speed circuit board not only has a large conduction area, but also has stable dielectric constant, high dielectric shielding requirements and high temperature resistance. At the same time, the bad phenomenon of delamination and mixed pressure warping caused by the differences in adhesion and thermal expansion coefficient between two different plates should be solved.
High uniformity of coating is required:
The characteristic impedance of the transmission line of the high frequency microwave board directly affects the transmission quality of the microwave signal. There is a certain relationship between the characteristic impedance and the thickness of the copper foil, especially for the microwave plate with metallized holes, the coating thickness not only affects the total thickness of the copper foil, but also affects the accuracy of the wire after etching. therefore, the size and uniformity of the coating thickness should be strictly controlled.
Laser micro-through hole processing:
The important feature of the high-density board for communication is the micro-through hole with blind / buried hole structure (aperture ≤ 0.15mm). At present, laser processing is the main method for the formation of micro-through holes. The ratio of the diameter of the through hole to the diameter of the connecting plate may vary from supplier to supplier. The diameter ratio of the through hole to the connecting plate is related to the positioning accuracy of the borehole, and the more layers there are, the greater the deviation may be. at present, it is often adopted to track the target location layer by layer. For high-density wiring, there are connectionless disc through holes.
Surface treatment is more complex:
With the increase of frequency, the choice of surface treatment becomes more and more important, and the coating with good electrical conductivity and thin coating has the least influence on the signal. The "roughness" of the wire must match the transmission thickness that the transmission signal can accept, otherwise it is easy to produce serious signal "standing wave" and "reflection" and so on. The molecular inertia of special substrates such as PTFE makes it difficult to combine with copper foil, so special surface treatment is needed to increase the surface roughness or add an adhesive film between copper foil and PTFE to improve the adhesion.
