The reason is simple: the product is getting smaller. Many electronic devices, such as smartphones, tablets, blood glucose detectors and so on, are becoming more and more strict in size, and they are becoming more and more tight, so there is not much space for the connector. The trend also appears in the defence and aerospace fields, such as satellites, guided missiles and avionics, which require compact connectors to be met only.

With the increasing demand for smaller connectors, design engineers are faced with a series of new challenges. They can no longer link the design of the connector to the final stage of the project. The mini connector needs a deep thought. It requires designers to consider various factors such as encapsulation, durability, current load capability and replaceability.

Designers should consider the ease of replacement, especially in closed enclosure. Molex VITA 67 is an easy to replace micro connector.

Here are some design suggestions from the micro connector supplier. These suggestions not only come from the experts of connector design, but also the painful experience of designers, so it is worth the reference of designers.

1. Consider connectors in early design

"Engineers tend to focus too much on designing the overall system, and consider putting connectors in the final stage of design." Mitch Storry, head of the TE Connectivity product development and Engineering Department, said, "they think connectors are simple, so they can put the related design in the last stage. Then they are stuck in their own design. "

Storry has seen too many designers rush to design the story of connectors in the final stage of design. In many cases, he told us, the designers finally had to choose non - standard connectors to complete the design, which not only raised the cost, but also delayed the delivery time.

To avoid such problems, experts suggest that in the early days of the design, you should consider the connector you will use, and then keep the design space for them, and the design is around it.

"No one can hear you say, 'first of all, determine the connector you need,'" said Stephen T. Morley, a product development engineer at TE Connectivity, "but if they do, they can actually save them a lot of time and a lot of trouble."

2. understand the limitations of clear space

Although the thickness of miniature board to board connectors is usually less than 1 mm, they are also commonly used in tightly packed applications. In order to solve the potential packaging problems, the designer needs to consider the wiring on the PCB board and the additional wire attached to the connector.  "Because the spacing is smaller, you must make the wire and wire more narrow."

Also, remember that some connectors, such as flexible cable connectors, provide options for forward and backward flip. When designing the system, you need to consider these rollover methods. For example, a backward flip connector can be very difficult to access if there is another component on the back.

Finally, designers need to notice that surface mounting devices sometimes fail to process smaller components. In some cases, they need new vacuum nozzles to solve these problems.

3. make clear the capacity of current load

As the connector size decreases, the current load capacity of the connector also decreases. Generally speaking, the micro connector can handle the current between 200mA and 500mA, which is about half of the larger plate to plate connector rated current. In order to compensate for the problems caused by lower current carrying capacity, designers may need to increase the number of terminals.

4. consider the stability of small / micro connections

"I need to recommend this, not only in the design stage but also in the assembly process, to ensure that they will not be harmed." Morley of TE Connectivity says.

Morley, a micro connector design expert in RF applications, recalls that half of the connectors in the military and space applications he designed were destroyed at the test stage.

If you don't put the problem first, you may push up the cost, he said. Damaged connectors need to be reconfigured, refurbished and marked. Even more expensive, field replaceable connectors may need to be replaced, and such changes may extend the design time by one to two weeks.

"What should be paid attention to is to always give priority to existing connectors," Morley said. "If these connectors are not compatible with your design, consider your own design, which can save you a lot of time."

5. consideration of changeability

If the appearance of the product is closed, then you need a connector that can be replaced from outside. Otherwise, you need to do some welding work.

"The more you do, the more skilled you are in welding, but the higher the risk of damage to the whole system," Morley said.

6. understand the functional requirements of the connector

Suppliers need customers to fully express their needs, otherwise they may misunderstand the needs of customers. This is especially important when making custom connectors.

"It is essential to clarify the needs of the connector," Storry said. "If we are not clearly expressed or missing, we may ignore the key requirements of the design."

7. consideration of mechanical stress

Temperature, impact and vibration generate stresses between interfaces and circuits. Experts suggest that you should choose connectors that can avoid these forces.