Terminal Blocks - Headers, Plugs and Sockets

Part Number	Description / PDF	Quantity
691368300004B Würth Elektronik Midcom	TERM BLOCK PLUG 4POS STR 3.81MM	149
691321300020 Würth Elektronik Midcom	3.81 MM TERMINAL BLOCK HEADER, V	119
691361300014 Würth Elektronik Midcom	TERM BLOCK PLUG 14POS 3.81MM	26
691313710006 Würth Elektronik Midcom	TERM BLOCK HDR 6POS 90DEG 5MM	0
691365110002 Würth Elektronik Midcom	3.50 MM TERMINAL BLOCK PLUG, HOR	467
691340700003 Würth Elektronik Midcom	5.00 MM TERMINAL BLOCK PLUG, HOR	327
691373500020B Würth Elektronik Midcom	TERM BLOCK PLUG 20POS STR 5.08MM	0
691331510004 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, D	178
691320510008 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, D	80
691332510004 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, D	2
691318700003 Würth Elektronik Midcom	5.00 MM TERMINAL BLOCK HEADER, V	433
691345410003 Würth Elektronik Midcom	7.62 MM TERMINAL BLOCK PLUG, HOR	196
691348500004 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK PLUG, VER	238
691309310006 Würth Elektronik Midcom	TERM BLOCK HDR 6POS 90DEG 3.81MM	69
691345710003 Würth Elektronik Midcom	5.00 MM TERMINAL BLOCK PLUG, HOR	280
691331510016 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, D	27
691307500002 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, V	0
691311500022 Würth Elektronik Midcom	TERM BLOCK HDR 22POS VERT 5.08MM	60
691370710006B Würth Elektronik Midcom	5.00 MM TERMINAL BLOCK HEADER, H	99
691344710004 Würth Elektronik Midcom	5.00 MM TERMINAL BLOCK PLUG, HOR	210

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