Terminal Blocks - Headers, Plugs and Sockets

Part Number	Description / PDF	Quantity
691701540012B Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, H	250
691361300008 Würth Elektronik Midcom	TERM BLOCK PLUG 8POS 3.81MM	227
691314520106 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, 4	230
691312510004 Würth Elektronik Midcom	TERM BLOCK HDR 4POS 90DEG 5.08MM	2
691386700006 Würth Elektronik Midcom	TERM BLOCK HDR 6POS VERT 5MM	0
691327310008 Würth Elektronik Midcom	3.81 MM TERMINAL BLOCK HEADER, D	102
691305340012 Würth Elektronik Midcom	3.81 MM TERMINAL BLOCK HEADER, H	237
691359740005 Würth Elektronik Midcom	TERM BLOCK PLUG 5POS 5.08MM	0
691351400008 Würth Elektronik Midcom	TERM BLOCK PLUG 8POS 7.62MM	98
691304530010 Würth Elektronik Midcom	WR-TBL SERIES 3045_5.08 MM_SCREW	93
691320510010 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, D	60
691312510010 Würth Elektronik Midcom	TERM BLOCK HDR 10P 90DEG 5.08MM	9
691363310008 Würth Elektronik Midcom	3.81 MM TERMINAL BLOCK PLUG, HOR	223
691331510006 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, D	135
691353500014 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK PLUG, VER	25
691374500020B Würth Elektronik Midcom	TERM BLOCK PLUG 20POS STR 5.08MM	0
691340500003 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK PLUG, VER	160
691334500018 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, D	19
691359740003 Würth Elektronik Midcom	TERM BLOCK PLUG 3POS 5.08MM	0
691309510005 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, H	505

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