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PRODUCT SPECIFICATION:

Design and Manufacturing Analysis of a High-Density, High-Performance Video Transmission Circuit Board

This circuit board is a high-density 8-layer PCB designed for professional-grade wireless camera/video transmission modules. The solution employs FR4 TG130 high-performance substrate material and strictly adheres to key processes such as a 1.6mm board thickness, 1-ounce copper weight, 1-microinch immersion gold surface finish, and resin-filled vias. The design focuses on high-speed signal integrity, power integrity, and stringent impedance control to provide a reliable hardware platform for high-definition, low-latency wireless video transmission.

High Heat Resistance:
The glass transition temperature (Tg) reaches 130°C, ensuring the physical and electrical stability of the substrate during prolonged high-intensity operation of the transmission module. This effectively prevents issues such as substrate softening, delamination, or impedance drift caused by high temperatures.

Excellent Electrical Performance:
Within the 1–6 GHz frequency range commonly used for video transmission, the dielectric constant (Dk) and dissipation factor (Df) remain stable. This facilitates precise impedance control and reduces signal transmission losses, which is critical for maintaining high-definition video signal quality.

Stackup Design:
The 8-layer board has a thickness of 1.6mm, with both inner and outer layers using 1-ounce copper (~35μm). This thickness balances current-carrying capacity with the feasibility of fine-line processing.

Minimum Trace Width and Spacing:
The minimum trace width is 3.6 mil (≈0.091mm), and the minimum trace spacing is 4 mil (≈0.102mm). These specifications meet the demands for dense routing under modern highly integrated encoder and RF chip BGA packages, enabling high-density wiring within limited space.

Via Design and Processing:
The minimum via diameter is 0.2mm (≈8mil), a typical specification for high-density multilayer boards used to interconnect signal and power layers.

Resin Filling (Via Plugging) Process: This is a critical requirement. Resin filling effectively prevents short circuits caused by solder bead residue during wave soldering and provides a flat surface for subsequent "via-in-pad" designs (essential for routing under ultra-fine-pitch BGAs), facilitating component placement. Additionally, it eliminates air entrapment that could cause signal reflections, thereby enhancing signal integrity for high-speed signals and improving via reliability.

Surface Finish:
The use of 1-microinch Electroless Nickel Immersion Gold (ENIG) provides excellent flatness, oxidation resistance, and stable solderable contact surfaces. This is particularly suitable for RF circuits sensitive to losses and scenarios requiring repeated plugging and unplugging during testing.

Multiple Impedance Control Groups:
The video transmission board integrates various signals such as digital video, high-speed control, and analog RF, making strict impedance control essential.

By adopting FR4 TG130 laminate, an 8-layer structure with a 1.6mm thickness, and combining precision processes such as 3.6/4 mil trace width/spacing, 0.2mm minimum via diameter, resin-filled vias, and 1µ" ENIG surface finish—along with rigorous multi-group impedance control—a hardware platform suitable for high-speed, high-density, and highly reliable wireless video transmission modules can be successfully constructed. This design solution fully balances performance, process feasibility, and cost, providing a solid circuit foundation for next-generation high-definition, low-latency wireless video transmission devices. During PCB manufacturing, close collaboration with a manufacturer capable of high-precision control is essential to ensure that all technical requirements, particularly impedance and resin filling quality, are perfectly achieved.