Common Connector Types and Applications: A Complete Overview of USB, D-sub, RJ45, FPC, and More

1. USB Connectors: Ubiquitous and Evolving

🔌 Types: USB-A, USB-B, Micro USB, USB-C

💡 Applications: Consumer electronics, charging devices, data transfer, peripherals

• USB-A is the standard rectangular connector found on most laptops and desktops.

• Micro USB was commonly used in older mobile devices.

• USB-C, now the mainstream standard, offers reversible insertion, high data rates (up to 10 Gbps), and power delivery up to 100W.

USB-C is ideal for modern mobile devices, laptops, embedded systems, and IoT products.

2. D-sub Connectors: Rugged and Reliable

🔌 Types: DE-9 (commonly called DB9), DB15, DB25

💡 Applications: Industrial control systems, legacy serial ports, CNC machines, test equipment

• D-sub connectors are characterized by their D-shaped metal shield and multiple pin configurations.

• Despite being an older standard, they remain relevant in industrial and military applications due to their durability.

• Screw-locking mechanisms ensure a secure connection in high-vibration environments.

3. RJ45 Connectors: Networking Standard

🔌 Type: 8P8C (Eight Position, Eight Contact)

💡 Applications: Ethernet networking, PoE (Power over Ethernet), routers, switches

• RJ45 is the standard connector used in Cat5e, Cat6, and Cat7 Ethernet cables.

• Supports Gigabit or higher data rates, often used in LAN and telecommunications systems.

• Variants with shielding (STP) are used in high-EMI environments.

4. FPC/FFC Connectors: Compact and Flexible

🔌 Types: FPC (Flexible Printed Circuit), FFC (Flat Flexible Cable)

💡 Applications: Smartphones, tablets, cameras, LCD modules, medical devices

• Used to connect thin, flexible printed circuits where space is limited.

• Available in ZIF (Zero Insertion Force) or non-ZIF types.

• Ideal for internal connections in compact electronics.

5. Circular Connectors: Durable in Harsh Environments

🔌 Types: M8, M12, MIL-spec, aviation plugs

💡 Applications: Robotics, automation, medical equipment, outdoor electronics

• Circular connectors offer excellent sealing against dust, water, and vibration.

• Common in automated machinery and outdoor installations.

• Bayonet or threaded coupling mechanisms provide secure mating.

6. Board-to-Board and Wire-to-Board Connectors

💡 Applications: PCB module interconnection, internal wiring, embedded systems

• These connectors bridge electrical connections between two or more PCBs.

• Available in vertical, right-angle, mezzanine, and custom configurations.

• Critical for modular designs, easy maintenance, and space optimization.

7. Coaxial Connectors: For High-Frequency Signals

🔌 Types: SMA, BNC, TNC

💡 Applications: RF systems, antennas, oscilloscopes, broadcast equipment

• Designed to carry high-frequency signals with minimal interference.

• SMA connectors are widely used for GPS, LTE, and 5G modules.

• BNC is popular in video and test equipment.

Conclusion: Choosing the Right Connector Matters

Each connector type serves a unique purpose, and the wrong choice can lead to performance issues, mechanical failures, or costly redesigns. When selecting a connector, always consider:

• Signal type (power, data, RF)

• Environmental factors (temperature, vibration, moisture)

• Size and form factor

• Mating cycles and ease of replacement

At Dmax, we help startups and SMEs choose the right connectors and build custom cable assemblies that meet their design, budget, and performance requirements.