Important Guidelines of Design for Manufacture and Assembly of PCBs – Part I

Designing a Printed Circuit Board (PCB) requires a proper planning of time and budget. Poor planning can cause you to spend more, and cost you time delays. Therefore, it is very crucial to take every decision in PCB design and manufacture properly. The poor performance of a PCB can be prevented by opting to do prior planning, which includes Design for Manufacture and Assembly (DFMA). What is DFMA? Read on the following post, which discusses what is DFMA and what are its guidelines.

What is Design for Manufacture and Assembly for a PCB?

Design for Manufacture and Assembly is basically the concoction of the following two methodologies:

• Design for Manufacture: The design for manufacture or DFM is responsible for simplifying the parts manufacturing to form a product.
• Design for Assembly: As the name suggests, Design for Assembly is the design, which helps simplify the assembly.

What are the Guidelines of Design for Manufacture and Assembly of PCBs?

There are certain guidelines given by Design for Manufacture and Assembly that are required to be followed. What are these guidelines? Read on to know.

1. Use Standard Components that are Commercially Available: This is the first and the most important guideline in manufacturing and assembling a PCB. You should always ensure that you use standard and commercially available components. This has several advantages:

•  Possibility of quantity discounts
• Reduces the time and efforts required for design
• Facilitates inventory control
• Helps avoid design of custom-engineered components

2. Reduce the Number of Components: It is not a good idea to make use of excess components. It is advisable to reduce the number of components used in an assembly. This not only reduces the costs, but also makes the final product more reliable owing to less connections. In addition to this, it reduces the work-in-process, as well as problems related to inventory control. Thus, you are required to purchase only a few components, which helps reduce the costs.

3. Think About a Modular PCB Design: It is always recommended to divide the PCB design into different functional blocks or modules. You can then use these modules in a wide range of products. There are several advantages in doing so. Dividing the PCB design in smaller modules, makes it easier to test and repair. This helps reduce the complexity, as well as the cost of testing. In addition to this, a modular PCB design also reduces per unit cost of the module ordered from a manufacturer. However, you should always weigh the cost benefits from modular design with the costs of increased number of interconnections using several modules.

4. Keep an Eye on the Tolerances: Always bear in mind that tolerances play a vital role in the designing of PCBs. You should always ensure that the tolerances are not tighter than the process capability.

5. Design Modules that are Compatible for Use in Several Products: If you wish to cut down on your product production costs and make verification schemes simpler, then you need to design a standard module that is compatible for use in a number of products. It makes it easier to find errors in a single module than testing an entire product. Additionally, when you choose to use modules, the design efforts can be reused across a wide range of projects.

These are just a few guidelines out of the many. We will discuss the remaining guidelines in the upcoming post. Stay tuned!