Terminal Blocks - Headers, Plugs and Sockets

Part Number	Description / PDF	Quantity
691348300002 Würth Elektronik Midcom	TERM BLOCK PLUG 2POS STR 3.81MM	646
691352510017 Würth Elektronik Midcom	TERM BLOCK PLUG 17POS 5.08MM	30
691311500009 Würth Elektronik Midcom	TERM BLOCK HDR 9POS VERT 5.08MM	338
691352710008 Würth Elektronik Midcom	TERM BLOCK PLUG 8POS 5MM	93
691344710005 Würth Elektronik Midcom	5.00 MM TERMINAL BLOCK PLUG, HOR	188
691386700002 Würth Elektronik Midcom	TERM BLOCK HDR 2POS VERT 5MM	100
691345410006 Würth Elektronik Midcom	7.62 MM TERMINAL BLOCK PLUG, HOR	99
691385700008 Würth Elektronik Midcom	TERM BLOCK PLUG 8POS STR 5MM	0
691333500010 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, D	80
691317510004 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, H	472
691352510021 Würth Elektronik Midcom	TERM BLOCK PLUG 21POS 5.08MM	20
691318400006 Würth Elektronik Midcom	7.62 MM TERMINAL BLOCK HEADER, V	249
691312510007 Würth Elektronik Midcom	TERM BLOCK HDR 7POS 90DEG 5.08MM	358
691305130005 Würth Elektronik Midcom	TERM BLOCK HDR 5POS VERT 3.5MM	100
691349340005 Würth Elektronik Midcom	TERM BLOCK PLUG 5POS STR 3.81MM	0
691331510008 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, D	186
691368300011B Würth Elektronik Midcom	TERM BLOCK PLUG 11POS STR 3.81MM	0
691382000004 Würth Elektronik Midcom	TERM BLOCK HDR 4POS VERT 2.5MM	276
691311500007 Würth Elektronik Midcom	TERM BLOCK HDR 7POS VERT 5.08MM	387
691348500006 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK PLUG, VER	155

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