The importance of specifying connectors early on in the design process

"Typically, with any design, it's all about the silicon on the pcb and people tend to work their way out, so of course the connectors are the last thing," said Jamie Furness, general manager UK, Ireland & South Africa at TTI. "I think most connector manufacturers would say – with good reason – that the connection should be considered earlier in the design." There needs to be a design to base it on, but as soon as the electronic infrastructure is defined, it's time to think about the connectors. Wendy Bourne, technical marketing engineer at Harwin, warned of the dangers of leaving connectors to the last minute. "Manufacturing works to lead times and if customers don't order to lead times, then there has to be a penalty somewhere," she said. This could mean they might have to compromise what they put in their design, be forced to wait until the right solution is available, or even pay a premium. Bourne cited examples where companies have tried to squeeze a connector on to the last few centimetres of a pcb to carry a current it is too small to handle. "They're trying to work against physics," she said. "If you've laid your board out and haven't left enough space for the connector you need, you've got to redesign your board." If the performance of the application might be dependent on a certain type of connector, Bourne emphasised that this needs to be known early on. "They think they're saving money at the front because they've designed in the cheapest connector they can, but they haven't considered all the factors that connector has to withstand," she said. Re-engineering costs both time and money, particularly when the test and measurement stage needs to be repeated – redoing vibrations and heat tests can be very expensive. For Furness, considering how to finalise the design is also critical, as is the importance of standards and specifications. "Probably the biggest bugbear of connector manufacturers is that people don't pay enough attention to the simple things, like crimping the connector and actually making sure that the spec to which they rate their connector is a spec they can back up," he described. He said that one mistake could be not paying attention to the actual application and not realising that the connector is going to be under adverse pressure. Then it won't perform to the spec they've given and the board may have to be redesigned. Jamie Lambert, technical sales engineer, interconnect, also at TTI, said that many oems and cems overlook environmental factors. "They don't tend to take into account things like mating cycles or how qualified the production staff are in actually assembling that particular connector," he said. "They don't take into account the stresses and the actual application. They just tend to concentrate on the connection itself." Instead of suffering the consequences of neglecting connectors, there are multiple financial incentives that flow from specifying them at the right time, according to Wim Henebiens, regional vp Benelux, and Marco Enge, senior product manager, interconnect, both at Avnet Abacus. "The earlier the product specialist can talk with the design engineer about the aim of their product, the easier it will be to reduce costs," said Enge. "The idea is not only reducing the costs of the acquisition of the connector, but reducing the costs in the design process and then later on with regards to the assembly of the product and the use of materials." There can be several levels of cost savings and finding the right product earlier can actually make assembly in the field easier. Enge also proposed that the earlier the customer gets in touch with a supplier, the more possibilities are available so they are not restricted by a specific design decision. "Engineers have another advantage by probably finding a customer specific design which could, for example, give their application an advantage over existing market solutions." Finding the right connector products early can potentially lead to a competitive advantage over other companies. Henebiens noted how, in the last three to five years, end product lifecycles in markets such as military are getting shorter due to innovation, while more electronics are appearing in markets such as automotive. "What you see is that products that have been used, defined and developed for automotive applications, come into use in high rel military applications, simply because it's a proven concept – proven in millions and millions of applications," he said. The effect of this trend, they argue, is an increased aftermarket focus once customers are actually using the products. "The ease of use of the product becomes a more important aspect," said Enge. "The interfaces are usually a very important part of the ease of use and the interconnection is very often a part of the interface." Furness described how distributors are now adding people in the field to offer tuition and guidance to customers in how to design in a connector – the proper steps you need to take and when they need to be taken – so it doesn't add time to the end of the project. An example is crimping courses. He noted how manufacturers have cut down on the value add and how that has fallen to distribution to handle. An example could be TTI's connector assembly service, launched last year. "There's an onus on the industry that distribution really needs to pick up," he said. "Value add as a label is really something that you're going to see more and more of." Could all these issues be linked to the electronics skills shortage and courses focusing on the visual side of design while overlooking other skills sets, or is it because there are increasing demands on electronic systems to consider? Bourne's advice for designers is simply to be aware that it's a lot more economical to work out connector issues on paper than it is at the final build stage. "Spend more time on the design phase – that's where it's cheapest to do it," she commented. "Get your design right. Consider every factor the system is going to go through." Specifying connectors early can save both time and cost, but according to Bourne, many designers still underestimate the importance of connectors projects. "You tend to get ones that have been bitten before who have learnt their lesson," she concluded. Ben Green, technical and marketing communications manager at Harwin quipped: "Possibly every generation of designers needs to learn the same lessons."