Printed Circuit Board Design Services

Understanding the Importance of PCB Design Services

The printed circuit board design process is the most crucial, as it determines a variety of aspects in the manufacturing process. The design of the PCB will determine the types of materials that will be used, the soldering processes, the type of printing, and mounting. Hence, it is essential that this phase be performed correctly, and to exact customer specifications.

Overview of PCB Design Services

As many companies offer PCB design services, each service offering will differ slightly. However, there are certain services that can be expected from all PCB manufacturing organizations. The details of these are given below:

• Schematic Capture: Also known as schematic entry, this is a part of the design cycle’s Electronic Design Automation (EDA) step. In this phase, a diagram of the electronic circuit is created by the designer.

• PCB Types: The PCB types can refer to the number of boards, or the type of circuit that is used in the PCB. Hence, PCB types will include:
  • Flex
  • Rigid
  • Rigid–Flex
  • Single Sided
  • Double-Sided
  • Multi-Layer

• High Density Interconnections & Surface Mounts:
  • BGA: A Ball Grid Array (BGA) is a surface-mount packaging assembly specifically used for Integrated Circuits (ICs).
  • CBGA: This stands for Chip Ball Grid Array. This is a BGA package with an addition of a chip design.
  • MBGA: This stands for Micro Ball Grid Array. This is a smaller sized BGA package.
  • Microvias: These are minute holes drilled by a laser to generate electrical connections between the layers in a multilayer circuit board.
  • Blind and Buried Vias: Blind and buried vias are used to connect between layers of a PCB where space is less. A blind via connects an outer layer to one or more inner layers, but does not go through the entire board. A buried via connects two or more inner layers, but does not go through to an outer layer.

• Design Types:
• Analog: These are circuits that provide continuous or analog signals. The currents and voltages alter or fluctuate with time. However, there are no abrupt transitions between levels.
  • Digital: In a sense, these designs are the opposite of analog PCBs. They provide intermittent signals. However, the voltages and currents may not fluctuate as much.
  • Mixed: As the term suggests, this is a combination of analog and digital designs. The size of this design varies, depending on the application.

• Auto Routing: Routing consists of creating geometries where the right terminals are connected to the right netlist. With advancements in PCB design software, this service has been transferred to CAD software. With this software, The PCB Auto Router is a feature of the CAD software that places traces automatically, often saving substantial time and effort. This service is particularly for multi-layer designs with high densities.

• Database Construction and Verification: The schematic capture process creates a database of symbolized parts and a netlist describing the connections between the symbols. One common feature among popular schematic capture packages is an array of libraries. Another is the ability to output netlists that are compatible with various simulation and PCB layout packages.

• Signal Integrity: This refers to the quality of a signal. This is important as PCB signal traces carry much more current than their on-chip counterparts. This larger current induces crosstalk primarily in a magnetic or inductive mode as opposed to a capacitive mode. To combat this crosstalk, digital PCB designers must remain acutely aware of not only the intended signal path for every signal, but also the path of returning signal current for every signal. The signal itself and its returning signal current path are equally capable of generating inductive crosstalk.  

• Design Verification: This is where the PCB’s design is validated before the designers move onto the layout stage. It ensures that the design has been implemented correctly. A software package is used to assist in the design checking and debugging processes.

• EMI Checking: This stands for Electromagnetic Interference (EMI). The checking refers to the tests that are performed on the PCB to ensure that the signal integrity is meeting the application requirements and customer’s expectations.