PCB Design Guidelines
Prototyping Considerations for Indian Products
Updated: 25 March 2021
One of the hardest things for us in PCB design has to be attempting to design a PCB for another country without being able to communicate with an expert from said country or visit the country. Even with individual provinces, major changes in environment, social attitude, and quality of life can differ drastically. This post attempts to address major (generally unforeseen) considerations when designing PCBs for the country of India, and there are limited resources that gather these considerations in one place. This article will be updated when we obtain new and relevant information, so as to keep up to date for the designers, prototypers, and developers looking to develop something for India.
ADI is a product design and development studio that almost never takes on the same project twice. Unlike manufacturing houses, which are streamlined in capability and therefore usually have trade secrets regarding their knowledge and SOPs for designing in specific countries, we – and many other design houses, startups, and SMEs – encounter many of these localised customs that can become obstacles to our work. Any additional contributions to the points below are appreciated.
Towards the end of one of our projects, we found that any prototypes sent to our client in India just would not work. They worked just fine in our office, and we wrapped them in many layers of care, and we sent them via DHL – which, as far as we know, is about the safest we can get them to be. Nothing worked and we couldn’t figure out why until our staff figured out that it was because of electrostatic discharge, or ESD. India, which has higher levels of static in its environment due to humidity, basically made ESD considerations paramount for the product we were designing to work. The most current standard at the time of update is ANSI ESD S20.20, of which the ESD Association has plenty of information on.
This wouldn’t be so much of a problem if one of the requirements hadn’t been in regards to size. At that point, the PCB was as miniaturised and optimised as we could get it to be, and the new requirement would force us to increase the size of the PCB, which was unacceptable to the client. In this case, we collectively (unhappily) decided to extend the project and redo the PCB design to include ESD considerations and still retain its size. For this subsequent version, we took the following measures while prototyping:
- Limit user interaction with the electronics and PCB to reduce the chances of static being introduced to the system. In our case, the only interactions the user had were the on/off button and the charging port. The product casing used a static-resistant material as well.
- Connect all components via copper land.
- Use ESD suppressors at external points of contact – we used a TVS in this case, but many companies (such as Murata) offer ESD protection devices for various uses.
- Keep the land separate from ground routing and practice good grounding
- Treat all components as static-sensitive devices (SSD)
- Reduce looping and trace lengths.
- Store and work in controlled environments that limit ESD. The ESDA has in-depth explanations on what this looks like in manufacturing and production.
- Ensure everything in the area is at the same potential to reduce current flow.
- Use ESD protective equipment if available, such as mats.
- If you are working alongside a chosen manufacturer already, speak with them about the processes for ESD protection and management. Begin to draft the process and testing procedures for the product as well, and ensure that the manufacturer can execute as necessary.