Switches are an indispensable component of numerous electrical devices, and their primary function is to regulate circuits by either completing or breaking them. A switch completes a circuit when turned on and breaks it when turned off. Although there are several types of switches available, PCB switches have been gaining popularity as a substitute for conventional switches in recent times. Therefore, in this article, we will explore the essence of PCB switches, their functionalities, and their comparative advantages over traditional switches.
What’s A Switch ?
A Switch is an electrical device that regulates the flow of a circuit, either by closing the circuit (ON) or cutting it off (OFF). When switched on, the circuit becomes complete, and when switched off, it breaks. The ideal switch has zero impedance when closed and infinite impedance when open.
PCB switches are available in various types, such as the push button, toggle switch, rotary switch, and PCB switch, among others. Surface mount (SMD/SMT) switches are designed to be placed flat on the top pads of a printed circuit board (PCB) so that they can be easily attached through surface mounting techniques. On the other hand, through-hole (or thru-hole) PCB switches are inserted into a drilled and plated-through hole (PTH) on the PCB and soldered to pads on the opposite side. These switches offer differing benefits, depending on the particular application they’re being used for.
What is Printed Circuit Board Switch ?
A PCB switch is an electrical component integrated into a printed circuit board (PCB) to control a circuit by completing or breaking it. Turning a switch on activates the circuit, whereas turning a switch off breaks the connection. PCB switches are available in various forms suitable for different types of printed circuit boards, including the PCB push-button, PCB micro switch, toggle switch, MEC switch, DIP and coded rotary switch, rocker switch, among others.
In recent times, PCB switches have grown in popularity among both designers and PCB users worldwide and have gradually replaced traditional switches. As such, it is essential to understand the nature of PCB switches, their applications, and the benefits they offer over conventional switches.
Benefits of PCB Switches
While there are various types of electrical switches available in the market, a growing number of businesses and even consumers prefer PCB switches for their superior characteristics. One of the most significant advantages of PCB switches is their ability to facilitate the flow of electricity with minimal resistance. They are made of highly conductive materials, such as copper, to provide a lower level of electrical resistance.
In addition to excellent electrical conductivity, PCB switches are also highly reliable in harsher environments, including outdoor use. Unlike most conventional switches, PCB switches can withstand extreme conditions caused by outdoor elements. PCB switches support a variety of plating options, such as gold-plated PCB switches.
PCB switches can also be customized to support different backlighting solutions, allowing for greater flexibility in design. Common backlighting solutions for PCB switches include LEDs, light guides, electroluminescent (EL), and fiber optics. Additionally, PCB switches support various soldering methods, including hard soldering and epoxy-based soldering.
Even though printed circuit boards have been widely in use for decades, recent technological advancements have improved their overall performance and designs. Consider utilizing a PCB switch if you are looking for an electrical switch and wish to benefit from the many advantages mentioned above.
PCB Switch Design Considerations
When designing PCB switches, various factors have to be considered. These design considerations include:
● Contact Materials: The materials used in the switch’s contacts determine its conductivity and durability. Common materials include gold, silver, and copper, with gold being the most durable.
● Actuation Force and Travel: The amount of force required to activate the switch and the distance the switch travels play a significant role in determining the switch’s suitability for a particular application.
● Lifecycle and Durability: The expected lifespan of the switch is essential, especially in critical applications where reliable operation is mandatory.
● Mounting Requirements: The switch mounting style, including PCB mounting or panel mounting, determines how the switch will be installed in the system.
By considering these design factors, a designer can select the appropriate PCB switch for a specific application and improve the performance and reliability of the end product.
PCB Switch Manufacturing Process
The manufacturing process of PCB switches may vary depending on the switch type and the manufacturer. However, some common steps in the manufacturing process are:
● Material preparation: The appropriate materials, such as the switch contacts and housing, are selected and prepared for manufacturing.
● Assembly: The switch assembly involves combining various components such as the contact mechanism, actuation mechanism, and housing.
● Testing: The assembled switches are subjected to various tests to verify their functionality and durability.
● Packaging: The manufactured switches are packaged for shipment to the end-users.
The exact manufacturing process can vary based on the type of PCB switch being produced, the production volume, and the manufacturing method, such as manual or automated manufacturing.
How to Plate Mounting of PCB Switch ?
Plate-mounted PCBs involve the installation of switches on a metal plate placed above the printed circuit board, with the switches then soldered on the PCB after being placed on the metal plate. This installation method reinforces and stabilizes the keyboard while also providing heavier key feel. Plate-mounted PCBs are commonly used in larger keyboards that require more support due to their size, offering extra rigidity and secure attachment to the keyboard.
Plate-mounted PCBs differ from PCB-mounted switches in that they do not require the extra guiding pins that a PCB-mounted switch requires (3 or 5-pins) as the switch is mounted on the plate rather than the PCB. It is worth noting, however, that removing the plate once the switches are soldered becomes considerably challenging.
What is DIP PCB Switch ?
In the electronics industry, DIP stands for ‘dual in-line package’ when referring to switch types. A DIP switch is a set of small, manual electronic switches designed to be packaged with other circuits. The term DIP switch may refer to either an individual switch on a multi-switch unit or the unit as a whole.
The primary function of DIP switches is to enable users to regulate the flow of electricity around a printed circuit board (PCB), expansion card, or other electronic or computer peripheral, thereby changing the operating mode of a device. When installed on a PCB alongside other electrical components, DIP switches provide users with the potential to customize the behavior of the electronic device, allowing for greater control over the precise function it performs in various scenarios or applications.
A row of tiny toggle (on/off) switches, resembling a series of miniature standard light switches, is typically used to present DIP switches mounted sequentially on a block of heat-resistant thermoplastic polymer. As a complete component, a set of DIP switches is usually quite small, requiring manual dexterity to toggle each switch between on and off positions. In practice, this function is often performed using the tip of a sharp pencil or a similarly shaped tool since the individual switches themselves are frequently too small for comfortable finger operation.
The Working of the DIP PCB Switch
A surface-mountable DIP PCB switch typically constitutes a basic assortment of two-terminal (1/0) electromechanical switches assembled inside a thermally stable housing. Although referred to as “jumpers,” they technically represent an alternative to traditional jumper switches.
● The “dual in-line” acronym segment refers to the contact pin organization located beneath the DIP switch that plugs directly onto the breadboard or PCB, arranged in dual parallel rows beneath the switch block, hence the name “dual in-line.” This switch type features twice the amount of contact pins compared to switches on existing modules.
● DIP PCB switches prove useful when selecting a specific device function and require multiple switches to toggle various modes. Their most common use involves deployment on computer motherboards, where different configuration settings require the toggling of different switches to different positions.
● A typical DIP PCB switch can consist of one, two, four, seven, eight, ten, sixteen, or more rocker, toggle, rotary, or slide switches mounted into a small block. Although they are simple components, it is possible to move the 1/0 independently, providing a large number of diverse combinations.
● Each toggle in a DIP PCB switch range gets electrically secluded from each other. Moving the toggle between on/off positions causes a flexible leaf spring beneath the switch to react to the rocker or slider movement, bending slightly downward or upward to open or close a static contact below.
● DIP PCB switches get categorized for specific applications and roles, especially regarding their safe operational power rating, voltage, and current. It is crucial for users to adhere to and observe the manufacturer’s specifications regarding a specific DIP switch; otherwise, problems may occur, such as electrical arcing and self-welded switches, jeopardizing device performance or integrity.
Different types of DIP PCB switches apply to arcade machines, testing and measurement devices, editing and production equipment, machinery and industrial sector controls, and automated garage doors, among others.
Future Developments in PCB Switch Technology
The advancements in technology continue to influence the future of PCB switch technology. Some of the expected developments in PCB switch technology include:
● Miniaturization: Manufacturers are working towards producing smaller switches that are suitable for use in compact electronic devices such as wearables, smart homes, and IoT devices.
● Improved durability: There is a continued need for more durable PCB switches that can withstand harsh environments, undergo numerous switching cycles, and maintain their performance.
● Increased automation: Automation technologies may improve the production process and reduce the cost of manufacturing PCB switches.
● Enhanced functionality: Advanced PCB switches may offer additional functionality, such as wireless connectivity, haptic feedback, and programmability.
● Environmentally friendly: The shift towards more sustainable and environmentally friendly electronics is likely to influence the development of eco-friendly PCB switches with reduce production waste and use of harmful materials.
Overall, the future developments in PCB switch technology will continue to focus on improving the performance, durability, and functionality of the switches and meeting the emerging needs of modern electronics across various industries.
PCB switches are critical components in electronic systems that allow for the control of circuits and functions. Understanding the different types of switches, their applications, and design considerations is essential when selecting the appropriate switch for a particular system. It is also important to consider the manufacturing process used in producing the switches to ensure their reliability and performance in the end product. As technology advances, there is a continued need for the development of more efficient and reliable PCB switches to meet the demands of emerging applications in various industries.
Therefore, for circuit board designers, carefully considering the aspects of PCB switches discussed in this article is critical to ensure optimal performance and functionality of electronic devices. Should any inquiries arise regarding PCB switches, we encourage interested parties to contact us via the communication channels available on our website. Our team of knowledgeable professionals is ready to assist with any questions or concerns that may arise.