Terminal Blocks - Headers, Plugs and Sockets

Part Number	Description / PDF	Quantity
691381000004 Würth Elektronik Midcom	TERM BLOCK PLUG 4POS STR 2.5MM	234
691311500117 Würth Elektronik Midcom	TERM BLOCK HDR 17POS VERT 5.08MM	88
691344410005 Würth Elektronik Midcom	7.62 MM TERMINAL BLOCK PLUG, HOR	146
691351700003 Würth Elektronik Midcom	TERM BLOCK PLUG 3POS 5MM	52
691340500012 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK PLUG, VER	47
691311400108 Würth Elektronik Midcom	TERM BLOCK HDR 8POS VERT 7.62MM	284
691364300012 Würth Elektronik Midcom	3.81 MM TERMINAL BLOCK PLUG, VER	88
691322310022 Würth Elektronik Midcom	3.81 MM TERMINAL BLOCK HEADER, H	120
691351400006 Würth Elektronik Midcom	TERM BLOCK PLUG 6POS 7.62MM	201
691311500121 Würth Elektronik Midcom	TERM BLOCK HDR 21POS VERT 5.08MM	57
691373500009B Würth Elektronik Midcom	TERM BLOCK PLUG 9POS STR 5.08MM	0
691320510016 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, D	19
691344510002 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK PLUG, HOR	349
691701540010B Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, H	500
691368300007B Würth Elektronik Midcom	TERM BLOCK PLUG 7POS STR 3.81MM	0
691314520123 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, 4	30
691352510024 Würth Elektronik Midcom	TERM BLOCK PLUG 24POS 5.08MM	16
691367310002 Würth Elektronik Midcom	3.81 MM TERMINAL BLOCK PLUG, HOR	589
691701500004B Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, V	300
691311500011 Würth Elektronik Midcom	TERM BLOCK HDR 11POS VERT 5.08MM	238

Terminal Blocks - Headers, Plugs and Sockets

1. Overview

Terminal blocks, headers, plugs, and sockets are essential components in electrical and electronic systems for establishing reliable connections between circuits. These devices enable signal transmission, power distribution, and system modularity. Their standardized designs ensure interoperability, scalability, and ease of maintenance in complex systems.

2. Main Types and Functional Classification

Type	Functional Characteristics	Application Examples
Terminal Blocks	Screw/clamp-based connections for high current/ voltage	Industrial control panels, power distribution units
PCB Headers	Pin/grid arrays for board-to-board connections	Embedded systems, Arduino shields
RJ Connectors	Modular jacks for data/telecom signals	Ethernet networks (RJ45), telephone systems (RJ11)
D-Sub Connectors	Multi-pin trapezoidal shells for analog/digital signals	Legacy serial interfaces, industrial sensors
USB Connectors	Hot-pluggable interfaces for power/data	Consumer electronics, peripheral devices

3. Structure and Components

Typical structures include:

Insulating housing (PA66, PBT, or LCP plastics)
Contact elements (phosphor bronze, beryllium copper)
Plating materials (gold, tin, nickel for corrosion resistance)
Actuation mechanisms (screws, spring clamps, or friction fits)
EMI shielding layers (for high-frequency applications)

4. Key Technical Specifications

Parameter	Importance
Current Rating (A)	Determines power handling capacity
Voltage Rating (V)	Defines dielectric strength requirements
Contact Resistance (m )	Impacts signal integrity and power loss
Insertion Loss (dB)	Critical for high-speed data transmission
Mating Cycles	Indicates mechanical durability
Operating Temperature (- C to + C)	Defines environmental tolerance

5. Application Fields

Primary industries include:

Industrial automation (PLCs, HMIs)
Telecommunications (5G base stations, routers)
Consumer electronics (smartphones, wearables)
Medical equipment (imaging devices, patient monitors)
Automotive (EV charging systems, ADAS)

6. Leading Manufacturers and Products

Manufacturer	Representative Product
Phoenix Contact	COMBICON series terminal blocks
TE Connectivity	MICRO MATCH connectors
Molex	SL Series headers
Amphenol	D-Subminiature connectors
Samtec	QTE high-speed socket systems

7. Selection Guidelines

Key considerations:

Electrical requirements (current/voltage levels)
Mechanical constraints (space, vibration)
Environmental factors (temperature, humidity)
Signal integrity needs (frequency, noise rejection)
Cost vs. reliability trade-offs
Compliance with standards (IPC, IEC, UL)

8. Industry Trends

Emerging developments include:

Miniaturization for wearable devices
High-speed connectors for 5G/6G ( 25 Gbps)
Hybrid connectors integrating power/data
Eco-friendly materials (halogen-free, RoHS compliant)
Smart connectors with built-in sensors
Automotive-grade connectors for EVs