In the product development cycle, there is a necessary process called DFM and DFA analysis. DFM is short for Design For Manufacturing while DFA means Design for Assembly.

First Step to take after receiving customer’s design

A designer can have the best design without any doubt. However, there is a limit in production capabilities. For example, in the PCB production, the standard minimum line width and space between inside layers is 4 mil and 4 mil. There are factories that can reach 3 mil and 3 mil. If the min. line width and space in your design is 2 mil, it is almost impossible for any factory to produce your PCB. Another example is that customer will request a stack up, however, as the thickness of raw materials varies, there might be another engineering query for change of stack up.

There are more items to be analyzed like this. And this is why every factory will have an engineering team to check the production files of the PCB, which includes but not limited to gerber files, drilling files, Bill of Materials, Pick-and-Place files, IPC netlist.

Normally, factory will send customers a EQ (Engineering Query) in order to help customers either confirm or choose one alternative solutions in the PCB production phase.

Apart from PCB production, DFA is also necessary in assembly process. When we first receive BOM from a customer, we need to revise it to the format we use, combining the same component used at different places of the circuit board, in most cases, capacitors and resistors. Then, we need check all the availability of components, including the connectors and ICs. From time to time, we encounter issues like there is no availability of certain component chose by the customer. We will have to recommend a replacement for the customer to check and confirm. Sometimes, we can’t find a replacement with the same print or foots if a component is outdated and the manufacturer doesn’t produce it any more. In this case, this will require the customer to check other options and choose one that fit their product design and modify the circuit board as well.

Case Study

We also met one case that we have to customize a part specifically for a project. Below we are going to show you a case where a transformer has to be customized.

Project Background

A customer from Middle East designed a PCB used in a lamp. The PCB is standard 2-layer board, with standard FR4 material and HASL surface treatment.

There is a transformer in the BOM that was very difficult for us to get. The customer sent us the following descriptions of the transformer they requested together with a picture.

How Heneng customizes a transformer to help facilitate customer’s project?

Our engineering team spent two weeks sourcing the part while analyzing the features. However, there is no same product available in the market. To proceed, one of our engineers contacted a factory that produces transformers here in Shenzhen, and it engineers, so we were able to define the details of the transformer and made a few prototypes. At first time, it doesn’t work. Finally, after a few rounds of trial, we were able to define the cause and changed size of wires from 0.04mm to 0.05mm width and rounds.



During 4 weeks’ designing and testing, we finally tailor-made a transformer that fits our customer’s needs for this product. Below is a picture of the final PCBA.

We, Heneng, always try to meet our customers’ needs. As our CEO always said, “Customer satisfaction is our top priority”.

With the technology know-how in PCB, we provide the turnkey PCB solutions for international markets. Services we provide includes DFM, PCB manufacturing, BOM purchasing, Assembly, Testing, Casing, QA, Logistics and more.

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