Terminal Blocks - Headers, Plugs and Sockets

Part Number	Description / PDF	Quantity
691338500008 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, D	119
691358310005 Würth Elektronik Midcom	TERM BLOCK PLUG 5POS 3.81MM	0
691357310004B Würth Elektronik Midcom	3.81 MM TERMINAL BLOCK HEADER, D	180
691305540004 Würth Elektronik Midcom	WR-TBL SERIES 3055_5.08 MM_PCB H	684
691321100003 Würth Elektronik Midcom	TERM BLOCK HDR 3POS VERT 3.5MM	1230
691367110006 Würth Elektronik Midcom	3.50 MM TERMINAL BLOCK PLUG, HOR	265
691330300008 Würth Elektronik Midcom	3.81 MM TERMINAL BLOCK HEADER, D	120
691309510006 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, H	320
691348300003 Würth Elektronik Midcom	TERM BLOCK PLUG 3POS STR 3.81MM	486
691365310003 Würth Elektronik Midcom	3.81 MM TERMINAL BLOCK PLUG, HOR	479
691351500018 Würth Elektronik Midcom	TERM BLOCK PLUG 18POS 5.08MM	54
691332510016 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, D	19
691385700002 Würth Elektronik Midcom	TERM BLOCK PLUG 2POS STR 5MM	0
691321300024 Würth Elektronik Midcom	3.81 MM TERMINAL BLOCK HEADER, V	103
691328310016 Würth Elektronik Midcom	3.81 MM TERMINAL BLOCK HEADER, D	57
691309410004 Würth Elektronik Midcom	7.62 MM TERMINAL BLOCK HEADER, H	274
691322310019 Würth Elektronik Midcom	3.81 MM TERMINAL BLOCK HEADER, H	119
691382010008 Würth Elektronik Midcom	TERM BLOCK HDR 8POS 90DEG 2.5MM	470
691311400103 Würth Elektronik Midcom	TERM BLOCK HDR 3POS VERT 7.62MM	449
691386700004 Würth Elektronik Midcom	TERM BLOCK HDR 4POS VERT 5MM	1

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