How to choose PCB spacers
Selecting the right PCB spacers is a critical consideration in electronic assembly and design. These components play a pivotal role in ensuring the integrity, reliability, and organisation of PCBs and their associated components. It’s therefore essential to consider a number of factors before you commit to purchasing. This guide is designed to help you make the right choice, covering:
Understanding the Importance of PCB Spacers
Factors to Consider When Choosing PCB Spacers
What’s the Difference Between PCB Spacers and Standoffs?
Types of PCB Spacers and Their Applications
Material Selection for PCB Spacers
Understanding the Importance of PCB Spacers
PCB spacers, also known as electrical spacers, ensure the reliability, functionality, and durability of electronic devices. Foremost among their crucial functions is preventing short circuits within a PCB assembly.
PCB Spacers act as Insulators
By creating a physical separation between conductive traces, components, and distinct PCB layers, these spacers serve as insulators. They mitigate the risk of unintended electrical connections that could potentially lead to operational issues or component damage. This insulation becomes particularly pivotal in densely populated PCBs where components are closely packed, and maintaining precise spacing is imperative to avoid electrical interference.
PCB Spacers Manage Heat Dissipation
Circuit board spacers play a pivotal role in effectively managing heat dissipation within electronic devices. Efficient thermal management is paramount to prevent overheating and potential component failures. PCB spacers can be strategically positioned to elevate components, facilitating improved airflow and more efficient cooling. They can also function as mounting points for heat sinks or thermal pads, thereby enhancing the dissipation of heat away from sensitive components.
In essence, PCB spacers function as integral elements in regulating temperature within safe operational limits, significantly enhancing the overall reliability and extending the operational life of electronic devices. Beyond their apparent function as physical supports, these spacers emerge as essential components that optimise both electrical isolation and thermal control, ultimately ensuring the seamless functionality of electronic systems.
Learn more in our insightful guide, Understanding PCB Operating Temperature.
Factors to Consider When Choosing PCB Spacers
When it comes to selecting PCB spacers, there are several crucial factors to keep in mind. These considerations are fundamental in determining the reliability and effectiveness of electronic devices. By meticulously taking these factors into account, you can make an informed decision when choosing PCB spacers.
PCB substrate
This depends on the dielectric properties you require from your PCB. More often than not, you’ll be using Fibreglass such as FR-4 or Paperboard PCBs. Fibreglass PCBs deliver strength and flexibility, so it’s best to use a snap fit spacer. Paperboard PCBs are more rigid and can fracture without the right support. You can use a push spacer to give support without penetrating the PCB, even when there is no mounting point.
Learn more in Your PCB Substrate: a Guide to Materials.
Material Choice
PCB spacers come in various materials, including plastic and ceramic. The material you opt for should take into account electrical conductivity, thermal properties, and compatibility with the environment. For example, nylon PCB spacers are non-conductive and lightweight, whereas ceramic ones offer high-temperature resistance.
Dimensions and Sizing
PCB spacers are available in different heights and sizes. It is essential to ensure that the chosen spacer's dimensions align with the specific layout requirements of your PCB assembly, as they directly influence the separation between components and layers.
Space Limitations
The clearance space required between two PCBs directly affects the size of spacer or support you choose. If there is a need to stack multiple PCBs, then an active element such as a wing or arrowhead is recommended, particularly when using boards with lower weight tolerances.
Threaded vs. Non-threaded
Spacers can feature threaded holes for screws or remain non-threaded. The choice between them depends on whether you require additional fastening options or seek a simpler assembly process.
Mounting Method
Consider the mounting method that best suits your assembly process—options include adhesive-backed, snap-lock, or screw-mounted spacers. The choice also hinges on whether you need a permanent or removable solution.
Heat Resistance
In applications subject to elevated temperatures or where components are prone to overheating, selecting spacers that can withstand high temperatures without deformation is crucial.
Our experts have put together this guide to help you understand more: How to Prevent Your PCB from Overheating.
Environmental Suitability
Evaluate the operating environment, taking into account factors like moisture, exposure to chemicals, or UV radiation. Opt for spacers with the appropriate resistance to these environmental elements.
Compliance with Standards
Ensure that the selected spacers comply with industry-specific standards and regulations, particularly in critical applications such as medical devices.
Load-bearing Capacity
The weight and load-bearing requirements of the components being separated should be considered. Spacers should be chosen to support these loads without experiencing deformation or failure.
Ease of Installation
Factor in the compatibility of spacers with your assembly process. Depending on your requirements, you may opt for quick snap-in options or threaded spacers for more secure fastening.
Budgetary Constraints
While cost is a consideration, it should be balanced with the required quality and specifications. It's important not to compromise on quality, as this can lead to long-term issues.
Customisation Options
Sometimes custom-designed spacers may be necessary to meet specific requirements, such as unique shapes or mounting options. Talk to our experts, who can accommodate your needs.
Supplier Reputation
Procure spacers from reputable suppliers known for their product quality, reliability, and customer support. With over 50 years’ experience in developing and manufacturing spacers for PCBs, we’ve built a reputation for excellence.
What’s the Difference Between PCB Standoffs and Spacers?
The primary distinction between PCB spacers and standoffs lies in their design and function. PCB mounting spacers are typically used to create a consistent separation between PCB layers or between the PCB and other components, ensuring electrical isolation and preventing short circuits. They come in various shapes and sizes, including cylindrical, hexagonal, and round, and are often unthreaded.
On the other hand, PCB standoffs are threaded components that serve a dual purpose—they provide a specified separation between PCBs or components while also offering a means for secure attachment via screws or bolts. Standoffs come in both male and female versions, allowing for versatility in assembly and enabling components to be securely fastened in place. While both spacers and standoffs contribute to the structural integrity and organisation of electronic assemblies, standoffs also facilitate component mounting and securing.
PCB spacers and supports are also similar. PCB supports are responsible for providing structural stability and safeguarding a PCB within an enclosure, ensuring its secure positioning. While these components all contribute to the functionality and dependability of electronic assemblies, their primary functions diverge:
● Supports prioritise stability
● Standoffs concentrate on spacing and attachment
● Spacers offer adaptability in functionality
Types of PCB Spacers and Their Applications
These seemingly simple components come in a wide array of types, each uniquely designed to fulfil specific functions in various electronic applications.
Round Unthreaded Nylon Spacers
● Excellent insulation properties
● Lightweight for easy installation and removal, reducing assembly time and effort
● Good resistance to chemicals, oils, and solvents, ensuring their longevity and performance even in harsh environments
● Round unthreaded spacers also available in PVC, PS, and POM
Typically used: Electronic assemblies, automotive systems, industrial machinery, consumer electronics
● Supports heavily loaded circuit boards
● Prevents circuit boards from bending
● No through hole is required, which allows easy access to
the underside of the board
● Maximum operating temperature: 85 °C
● Nylon 6/6
Typically used: Electronic enclosures, automotive assemblies, telecommunications equipment, industrial machinery
● Excellent electrical insulation and thermal resistance
● Can be used as a non-threaded spacer for high powered devices
● Maximum operating temperature: 1000°C max temp
● Stackable parts for longer wire assemblies
Typically used: High-frequency PCBs where signal integrity is critical, such as wireless communication and radar systems. Also used for LED lighting, power electronics, and any application in a high-temperature environment
● Provides insulation for screws used to fix a circuit board to a panel
● Snaps into the board to ease assembly and maintain spacing even when the screw is removed
● Available in standard and stackable versions
● Nylon 6/6
Typically used: Electronic enclosures, automotive assemblies, telecommunications equipment, control panels, manufacturing systems, and robotics
● Supports heavily loaded circuit boards
● No through hole is required, which allows easy access to the underside of the board
● Flanged base for enhanced stability
● Maximum operating temperature: 110°C
● Nylon 6/6
Typically used: Electronic enclosures, automotive assemblies, telecommunications equipment, industrial machinery
Browse our Entire Range of PCB Spacers
Material Selection for PCB Spacers
What spacer materials are available? Selecting the ideal material hinges on the specific requirements of your PCB spacer application, encompassing factors such as electrical insulation, temperature resilience, cost considerations, and the prevailing environmental conditions. Our range includes ceramic and plastic PCB spacers:
Nylon 6/6:
● Effective electrical insulation: Excels at providing robust electrical insulation, preventing the risk of short circuits between conductive traces on the PCB.
● Lightweight: Nylon's lightweight nature proves beneficial in applications where minimising overall weight is essential.
● Cost-Efficiency: Nylon spacers are typically cost-effective, making them a practical choice for projects with budget constraints.
● Decent Mechanical Strength: While not as robust as metal alternatives, nylon 6/6 offers satisfactory mechanical strength.
Ceramic:
● Impressive High-Temperature Resistance: Ceramic spacers exhibit exceptional tolerance to elevated temperatures, rendering them suitable for demanding high-temperature environments where other materials might degrade.
● Exceptional Electrical Insulation: Ceramic's excellent electrical insulating properties ensure reliable isolation between PCB components.
● Dimensional Stability: Ceramics maintain their shape and size reliably, ensuring consistent spacing between components.
● Chemical Resistance: Ceramics demonstrate resistance to various chemicals and remain unaffected by moisture.
POM (Polyoxymethylene):
● Low Friction Characteristics: POM boasts low friction properties, which proves advantageous in applications requiring smooth movement or precise adjustment.
● Resilient Chemical Resistance: POM effectively resists a broad range of chemicals, making it suitable for deployment in diverse environments.
● Dependable Dimensional Stability: POM retains its shape and dimensions, assuring consistent component spacing.
● Minimal Moisture Absorption: POM exhibits low moisture absorption, ensuring its performance remains unaffected in humid conditions.
PS (Polystyrene):
● Cost-Efficiency: PS represents a cost-effective option for PCB spacers, rendering it suitable for projects with budgetary considerations.
● Adequate Electrical Insulation: PS delivers satisfactory electrical insulation for standard applications.
● Lightweight Feature: PS's lightweight nature contributes to reduced overall weight in assemblies.
PVC (Polyvinyl Chloride):
● Effective Electrical Insulation: PVC provides dependable electrical insulation properties, making it suitable for averting electrical interference on PCBs.
● Chemical Resilience: PVC stands resilient against a broad spectrum of chemicals, enhancing its versatility for different environmental conditions.
● Cost-Effective Option: PVC is generally an affordable choice, aligning with budgetary considerations for many applications.
● Lightweight: PVC spacers maintain a lightweight profile, which can be advantageous for weight-sensitive applications.
Download free CADs and try before you buy
Free CADs are available for most solutions, which you can download. You can also request free samples to ensure the PCB spacer dimensions you’ve chosen are exactly what you need. If you’re not quite sure which spacers will work best for your application, our experts are always happy to advise you.
Download FREE CADs in three easy steps
Whatever your requirements, you can depend on fast despatch.
Questions?
Email us at sales@essentracomponents.co.uk or speak to one of our experts for further information on the ideal solution for your application 0345 528 0474.