What is EMS?
An Electronic Manufacturing Service (EMS) supplier generally has the capability of design, manufacturing, testing, and packaging of electronic products which they carry out for third-party buyers. Their focus would be electronics such as PBC design and manufacture and then to offer as much added value to the product as possible.
This kind of supplier is capable of working with an original equipment manufacturer (OEM) by taking their product specification and designing a printed circuit board, producing the bare PCB, populating that PCB which is normally done via surface mount technology (SMT) machines, testing all the functions against the product specification, and then adding more value by including the PCB into other assemblies.
They can either source the additional added value components themselves or the buyer would get their inventory sent to the supplier for assembly work.
Here are three typical examples of how electrical manufacturing service suppliers work:
1. PCB Design & Manufacture
Buyer has a new product development project with no internal electronic capabilities. They have a detailed specification of what the product needs to do and how it functions. They send the specification to an EMS supplier who then designs the electronic circuit that will provide all the features and functionality of the product. The EMS then produces the bare PCB, populates the boards on their SMT flow line, tests the finished PCBs, and ships the finished PCBs to the buyer.
2. Assembly Level
Take the example above where the PCB is manufactured by the EMS, but in this case, the buyer needs some additional components added to make a sub-assembly. The EMS would purchase some components, and the buyer would source and send other components to the EMS. They would then complete all the assembly work (such as soldering connector wires to a motor or switch, assembling the PCB into a mounting cage, then adding different components to that assembly). Once all the assembly work is complete, they would ship these to the buyer.
3. Product Manufacture & Assembly
Continuing with the same example, but in this case, the buyer is looking for the EMS to complete the entire product. The buyer would normally source more of the non-electronic products and get those components sent to them. They would then assemble the entire product (remember, they only manufactured the PCB, and everything would be purchased from other suppliers). The final operation would be product testing and packing, then shipping the final product to the buyer.
You can read more about an EMS’ role in NPI in The New Product Introduction Process Guide for Hardware Startups.