Jason Cullen / October 14, 2021
It’s hard to imagine that it’s been nearly 50 years since the first prototype cellular phone was developed by Motorola. The DynaTAC 8000X weighed in at almost two pounds and was over seven inches in length. When it was released to consumers 10 years later, it sold at a retail price of $3,995. It is fascinating how far the consumer marketplace has evolved since then.
Today, it is routine to see an average person walking down the street wearing a watch that can make calls and perform a multitude of other tasks at a size of about 1.5 inches – at a retail price under $300.
Consumers and other stakeholders constantly demand more functionality and higher performance from their electronics in a smaller form factor. In addition, just as the example of the 8000X shows, there will always be pressure on manufacturers to reduce form factor to keep competitive in the market.
In the quest for designers to try and meet demanding requirements for thinner applications, extreme amounts of onboard electronics have to be stacked together in new and creative ways. Multiple stackups of onboard circuit board assemblies are required to meet functionality requirements for items such as wearables, medical sensors and other high-performance applications.
Plastronics has two pin designs that essentially enable the designer to solve a volume constraints issue in two completely different ways.
The T033, at 1.00mm compressed height, is Plastronics’ shortest pin assembly. The T033 can deliver a maximum current of 4.8 Amps with a signal performance rating of 50.1GHz at -1dB.
Not all applications will require a solution such as this, but the option is always there as programs evolve and requirements change. If a purely vertical solution is required, this is the closest to an invisible interconnect possible without the risks and challenges of a hard-soldered connection while still giving the designer 0.26mm of pin travel to allow for tolerance stackups between adjacent boards.
(On left) An example T033 Board-to-Board Connector between adjacent .062” Printed Circuit Boards (On right) The 1.00mm “T033” pin can carry 4.8 Amps with a signal loss of -1dB at 50.1GHz
In other scenarios, the user may need additional pin travel, or have an inability to secure a board-to-board connector in a traditional stacked configuration. This can be a difficult scenario as there are often few options without a completely customized solution. Plastronics has multiple H-pin solutions and an automated process for these scenarios.
The H033 utilizes the same spring as the T033, but with longer stampings to increase the available travel by more than 50 percent. If the H033 is used in the horizontal plane, it takes up only 0.33mm of space. The image below shows an example stackup in which the H033 is assembled between two adjacent flex circuits.
Combining the H033 with a series of flex circuits off the ends of the stacked board assemblies allows the user to make all required connections between the boards directly adjacent to the board stack using a header or buss bar style setup.
This option saves the user space in a scenario where they may be unable to allow for the use of standard hardware to provide the force needed to vertically actuate the H. The H033 setup shown would also work for scenarios involving side loaded connectors for a charging or programming setup, taking up a minimal amount of space while delivering maximum signal and power integrity.
An example H033 Board-to-Board Connector with Horizontal Plane attachment method for minimal stackup height
Designing the next generation of miniaturized custom electronics can be a daunting task. There is always going to be a balancing act between achieving maximum performance and offering high performance in the smallest possible form factor. But designers shouldn’t have to sacrifice on either without understanding all possible solutions for the interconnects within the assembly.
We’ve shown just a couple of examples of how the T033 and the H033 pin can be used to save you as much space as possible in your application. Plastronics has the ability to provide customers with individual pin solutions for connectors that they design themselves, OR fully customized connector assemblies we design in-house to meet their needs.
Plastronics has the application experience and available resources to help you optimize your next design. Reach out to us to help you find an optimal solution.
There’s an H-Pin for everything. Download our guide to see how you can lower your project costs without sacrificing performance.