Pogo Pins: From Engineering to Manufacturing
Pogo pins are reliable, spring-loaded pins used in electronics connectors. They sport several qualities that make them a versatile and trusted design choice — they come in a wide range of sizes, are easy to install and maintain, possess a small footprint, and are durable in challenging environments. Device manufacturers install pogo pin components in a wide range of products, from mobile device charging and testing equipment to automotive electronic subsystems, including airbags and dome lights. With both the benefits and applications of pogo pins in mind, let’s rewind and discuss both the engineering and manufacturing processes behind pogo pin production.
The Pogo Pin Design Process
When a device manufacturer approaches Mill-Max with a new project, its product engineering team knows the relative type of part it needs, as well as the size requirements. From there, the Mill-Max team employs its connector expertise while considering the intended use environment and other engineering constraints.
These “constraints” help move the design process in the right direction. The profile of the device design dictates the shape and size of the pogo pin connector. Proper material considerations need to be factored in for manufacturing and performance purposes. Brass is an excellent choice for precision machined components due to its exceptional machinability and high conductivity. Springs made from beryllium copper and stainless steel provide long-term durability, flexibility in design for force and stroke, and the ability to operate through a wide range of temperatures.
Gold plating is the standard for Mill-Max pogo pins. It allows for the precise, tight fit required by Mill-Max’s unique assembly processes, provides the necessary durability for high cycle life and delivers superior conductivity and corrosion resistance.
Determining Spring Force
Pogo pin connectors depend on spring force to establish and maintain a strong connection. Spring force — the force exerted by the internal spring within the pin onto the contact surface — plays a critical role in sustaining contact during shock and vibration, maintaining plunger pressure over prolonged cycle life, and overcoming high contact resistance residues. Another advantage of having ample spring force is that even if the pogo pins are not perfectly aligned to their corresponding mating pad or target pin, they will still form a reliable connection, ensuring consistent transmission of signals and power.
Design engineering teams need to define the spring force for the application at hand. The optimal force of the spring pin depends on the conductivity of the contact materials, the number of spring pins used in the application, the component’s pin size and design, and the environment – including the level of shock and vibration as well as temperature and humidity considerations. A spring force that is too low can lead to unreliable connections and increased contact resistance, while a spring force that is too high can cause premature wear and tear on the pins and contact surfaces.
Engineering Pogo Pins for Durability
Naturally, device manufacturers want their components to have long lifespans. The best way to achieve this is by using superior materials, smart design and quality manufacturing. Of course, size is often a limiting factor and can have a major impact on the durability of a pogo pin connector. Increasing the size of the pin, specifically the diameters and internal wall thickness, is one way to achieve longer lifespans. Larger diameters can provide more structural durability to the pin to resist bending and binding when alignment is imperfect or unexpected side loading is present. Spring materials also play a major role in the durability of pogo pins, primarily as they pertain to cycle life. Beryllium copper and stainless steel can provide up to a million cycles or more without losing spring properties. These materials also perform well at elevated temperatures.
Plating is another variable that affects component durability and increasing the gold plating — especially on the plunger — can extend connector life. Since the electrical contact is made at the tip of the plunger, thicker gold plating on this component is sometimes all that is required for additional protection against corrosion and wear, which causes intermittence. In short, the thicker the gold plating, the longer the component will last.
Establishing the Right Footprint
In a customer and component design consultation, a customer usually has a solid grasp of the space the pin needs to fit. Space constraints can lead to tradeoffs in pogo pin durability. However, the Mill-Max team can find the right solution to the footprint design challenge in most custom projects. By understanding and working through the challenges of space limitations, we create the right part with the right fit.
Inside the Pogo Pin Manufacturing World
After the initial design of the pogo pin is complete, further analysis is done to determine the proper tolerances for the machining and assembly of the components. Once these details are finalized, manufacturing begins. The component parts are machined, cleaned, inspected, plated and then assembled.
The next critical steps are screening and testing. This ensures all pin parts are correctly assembled, meet dimensional requirements, have the proper spring force, and perform as intended. Only the pogo pin connectors that pass these stringent tests are sent to customers.
Mill-Max's proprietary production methods are one of the major things that sets us apart from our competition. The Mill-Max team can ensure components are accurately executed by controlling the entire process in-house.
Mill-Max: Global Leaders in Pogo Pin Manufacturing
When approaching your next project, consider whether pogo pin connectors are the right fit for your device. Their versatility makes them a great choice in a wide variety of applications. The Mill-Max engineering team specializes in custom parts and offers a vast catalog of off-the-shelf pogo pin solutions. Contact Mill-Max for expert advice and to establish a great connection with a global connectivity leader.