24 June 2019
ELECBEE
9176

SMA Connector vs 3.5mm Connector: Key Differences & Performance Comparison

Compare SMA and 3.5mm connectors in terms of frequency performance, mechanical stability, and RF applications. Learn which connector suits your high-frequency or metering needs.

 

1.Overview of SMA Connector and 3.5mm Connector

SMA and 3.5mm connectors are widely used RF coaxial interfaces designed for high-frequency applications. The SMA connector is a 50-ohm interface originally rated to 18 GHz, while some high-performance versions can operate up to 24–26.5 GHz. The 3.5mm connector extends this frequency range and offers improved mechanical precision and signal repeatability, while the 2.92mm connector supports even higher frequencies for ultra-high-performance applications.

 

2.Technical Specifications and Frequency Performance

Feature

SMA Connector

3.5mm Connector

Characteristic Impedance

50 Ω

50 Ω

Frequency Range

Up to 26.5 GHz

Up to 34 GHz

Dielectric Material

PTFE (Teflon)

Air

Outer Conductor

Threaded

Threaded, higher precision

Loss / SWR

Higher at high frequency

Lower, better repeatability

The 3.5mm connector uses an air dielectric, providing lower insertion loss and better SWR stability, making it ideal for high-precision RF testing and calibration.

 

3.Mechanical Stability, Dielectric Material, and Durability

SMA connectors are compact, robust, and economical, suitable for general production applications. They withstand repeated insertions and moderate vibration but can be affected by pin damage or coating scratches over time. 

In contrast, 3.5mm connectors are designed for metering or high-performance test environments, offering tighter mechanical tolerances and higher temperature stability.

 

4.Applications: When to Use SMA vs 3.5mm Connector

• SMA Connector: Production use, general RF applications, cost-sensitive deployments.

• 3.5mm Connector: Calibration, metering, high-frequency testing, and situations requiring precise mechanical stability and low signal loss.

 

5.Key Differences and How to Choose the Right Connector

While SMA and 3.5mm connectors are compatible in some configurations, careful selection is crucial to avoid transmission loss or test inaccuracies. Consider the following:
    a. Frequency requirements
    b. Mechanical stability and insertion repeatability
    c. Signal loss and SWR performance
    d. Application environment (production vs metering/test)

 

6.FAQ: SMA and 3.5mm Connector Selection Tips

Q1: Can I mix SMA and 3.5mm connectors?

A1: Yes, but only if carefully paired; mismatched pins or coatings may affect performance.

Q2: Which connector is better for 5G or millimeter-wave applications?

A2: 3.5mm connectors are preferred for high-frequency or precision RF applications.

 

7.Conclusion

By understanding these differences, engineers and technicians can select the right connector for each application, ensuring stable performance and reliable measurements. For more technical details or to purchase high-quality SMA, 3.5mm, 2.4mm, 1.85mm, and 1.0mm connectors, you can contact us at support@elecbee.com or simply click the links below to place your order directly.

Related Products:

• SMA connectors

• 3.5MM Connectors

• 2.92MM connectors

• 2.4MM connectors

• 1.85MM Cable Assemblies

• RF Connector Adapters

• RF Connector Assemblies