At the core of the Cadence PCB design solution is the powerful and intuitive PCB Editor. This constraint-driven environment simplifies the creation and editing of PCBs, from basic to complex designs. It offers a wide range of features that address modern design and manufacturing challenges, providing flexible layout planning tools based on Allegro platform technology. These tools enhance productivity by reducing wiring time and accelerating time-to-market. The editor includes shape-based trace push capabilities, real-time length and timing tolerance display, and dynamic copper plating with real-time floor fill and repair during placement and routing. Additionally, it supports full negative film processing, bare board assembly, and test output in various formats, including Gerber 274x, NC drill, and more.
**Cadence PCB Routing**
**PCB Laminate Structure**
The choice of a layered structure is critical in PCB design. When selecting a stacking configuration, the following principles should be considered:
- The second layer (below the component side) should be a ground plane, acting as a shielding layer and reference for top-layer routing.
- All signal layers should be as close as possible to the ground plane.
- Avoid direct proximity between two signal layers.
- Place the main power layer adjacent to its corresponding ground plane.
- Ensure symmetry in the laminated structure.
- Both the component and solder sides should have complete ground planes (shielding).
- Avoid parallel wiring layers adjacent to each other.
- Key signals should be placed near a ground plane and avoid crossing partitions.
For a four-layer board, the preferred stack-up is: Signal – Ground – Power – Signal. For a six-layer board, the optimal structure is Signal – Ground – Signal – Ground (or signal if needed) – Power – Signal. For an eight-layer board, there are two common options. Option 2 provides more power layers and is suitable for boards with multiple power supplies. The stacking structure for higher-layer boards should follow similar principles, and further details can be found in additional resources.
The SMDK6410 core board, designed as an eight-layer board, requires careful setup of the stack structure, including rule configurations and PCB layout. To begin, open the "Cadence SPB 16.5" PCB Editor and load the PCB file. Click the "Cross-section" icon on the toolbar or select Setup > Cross-section. A dialog box will appear where you can manually add and adjust the layers. Right-click on the layer number to add, remove, or adjust the stack-up. An isolation layer must be placed between signal layers. After setting up the eight-layer board, the final structure should reflect the chosen configuration.
Each layer in the stack has a name, type, material, thickness, conductivity, dielectric constant, loss tangent, and whether it outputs as a negative. Conductive layers are used for traces, plane layers for grounds or power, and dielectric layers for insulation. Parameters like dielectric constant and thickness are essential for impedance calculations. Some layers, like POWER1 and GND2, may need to be set as negatives for specific manufacturing processes.
**Wiring Rules**
Setting up proper wiring constraints is crucial for successful PCB layout. These rules influence signal integrity, performance, and overall efficiency. Key constraints include differential pair settings, line widths, equal length matching, via configurations, and more. These rules are managed through the Constraint Manager.
To access the Constraint Manager, go to Setup > Constraints > Constraint Manager, or click the corresponding icon on the toolbar. The interface displays several worksheets, including Electrical, Physical, Spacing, and Same Net Spacing. Most rules are set in the first four worksheets. Electrical rules define signal types and connections, while physical rules determine line width, spacing, and other physical parameters. Properly configured constraints ensure accurate and efficient PCB design.
Laptop Stand Gaming Rgb,Laptop Stand Gaming Laptop,Gaming Laptop Stand Adjustable Height,Gaming Laptop Stand With Cooling,etc.
Shenzhen Chengrong Technology Co.ltd is a high-quality enterprise specializing in metal stamping and CNC production for 12 years. The company mainly aims at the R&D, production and sales of Notebook Laptop Stands and Mobile Phone Stands. From the mold design and processing to machining and product surface oxidation, spraying treatment etc ,integration can fully meet the various processing needs of customers. Have a complete and scientific quality management system, strength and product quality are recognized and trusted by the industry, to meet changing economic and social needs .
Laptop Stand Gaming Rgb,Laptop Stand Gaming Laptop,Gaming Laptop Stand Adjustable Height,Gaming Laptop Stand With Cooling
Shenzhen ChengRong Technology Co.,Ltd. , https://www.laptopstandsupplier.com