In this case, use at least 4 layer PCB. Recommended for breakouts, small and simple boards. Price is still reasonable and this PCB offers 4 solid ground planes or two additional signal layers. If your design has too many connections or uses high speed signals, add 2 more inner signal layers. I do not know any calculator to calculate number of PCB layers. Simply, use the steps I described and your own intuition. Hovewer, sometimes it may be hard to determine the smallest size of your PCB.
Of course, there are many options to order your PCB layers. Flexible PCB Manufacturing. Rigid-flex PCB Manufacturing. PCB Assembly Process. Aluminum Printed Circuit Board. Rigid-flex PCBs. Flexible PCBs. High-frequency PCBs. Thick-copper PCBs. Medical PCB. Metal core PCBs. Printed circuit board materials. SMT Assembly Capabilities. Mixed Assembly Advantages. Through-hole Assembly. Components Sourcing. Laser Stencil. Electrical Test E-test. Impedance control. RoHS-lead Free.
UL Certification. Layer orientation. Panel creation. Gold fingers. Surface finish. Via covering. Annular rings. Edge plating. Plated Half-holes. Plated-through slots. Prepregs, cores, foils. PCB price composition. Design rule check. The materials used as dielectrics provide two basic functions for the PCB.
As we build complex PCBs that handle high-speed signals, the dielectric materials isolate the signals found on adjacent layers of the PCB. PCB stability depends on the consistent impedance of the dielectric over the entire plane and the consistent impedance over a wide frequency range.
While the copper as a conductor seems obvious, other functions exist. Different weights and thicknesses of copper impact the ability of a circuit to achieve the correct amount of current flow and define the amount of loss. In terms of the ground and power planes, the quality of the copper layer impacts the impedance of the ground plane and the thermal conductivity of the power plane. Matching the thickness and length for differential signal pairs solidifies the stability and integrity of the circuit—especially for high frequency signals.
Physical dimension lines, dimension markings, datasheets, cut-out information, vias information, tooling information, and assembly instructions not only describe the mechanical or dimension layer but also serve as the measurements for the PCB foundation.
The assembly information controls the mounting and location of the electronic components. Other documents include the Bill of Materials, Gerber data, CAD data, the schematic, fabrication drawings, notes, assembly drawings, any test specifications, any quality specifications, and all regulatory requirements.
The accuracy and detail included in those documents lessens the opportunity for any errors in the design process. An electrician installing electrical wiring in a house must follow rules to ensure that the wire will not have sharp bends or become vulnerable to the nails or screws used to install drywall.
Running the electrical wire through stud walls requires a consistent approach to the depth and height of the wiring path. The keep out and routing layers establish the same constraints for a PCB design.
A keep out layer defines physical constraints—such as component placement or mechanical clearance—for the design software or electrical constraints like route keepouts. Routing layers establish the interconnections between components. Depending on the application and type of PCB, a routing layer can be placed on the top and bottom layers of a PCB or within the internal layers. Every house has a main electrical service panel or load center that receives incoming electricity from an electrical utility and distributes power to circuits that supply lights, outlets, appliances, and devices.
The ground planes and power planes of a PCB provide the same functionality by connecting the circuit to ground and by distributing different onboard voltages to components. As with a service panel, the power and ground planes can contain multiple copper sections that allow circuits and sub-circuits to connect to different potentials. Professional house painters carefully document the colors and finishes used for ceilings, walls, and trim. On a PCB, the silkscreen layers use text to designate the locations of components on the top and bottom layers.
Having the information available through a silkscreen saves a design team from referring back to assembly documents. The primers, paint, stains, and varnishes applied by house painters add appealing colors and textures.
In addition, those finishes protect surfaces from deterioration.
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