Gas Discharge Tube Arresters (GDT)

Image	Part Number	Description / PDF	Quantity	Rfq
	SL1011B260A Wickmann / Littelfuse	GDT 260V 10KA 2 POLE TH	0
	GTCN26-231M-P05-B Wickmann / Littelfuse	GDT 230V 5KA 2 POLE	0
	GTCN38-251M-Q10 Wickmann / Littelfuse	GDT 250V 10KA 3 POLE	0
	SL1011B090C Wickmann / Littelfuse	GDT 90V 10KA 2 POLE	0
	GTCA28-351L-P05 Wickmann / Littelfuse	GDT 350V 5KA 2 POLE THROUGH HOLE	0
	GTCR37-231M-P10-FS Wickmann / Littelfuse	GDT 230V 10KA 3 POLE TH	0
	GTCT37-551M-P10 Wickmann / Littelfuse	GDT 550V 10KA 3 POLE TH	0
	SL1021A145R Wickmann / Littelfuse	GDT 145V 10KA 3 POLE TH	0
	GTCA28-471L-P05 Wickmann / Littelfuse	GDT 470V 5KA 2 POLE THROUGH HOLE	0
	SL1024B450RF Wickmann / Littelfuse	GDT 450V 20KA 3 POLE TH	0
	SL1021B350RG Wickmann / Littelfuse	GDT 350V 20KA 3 POLE TH	0
	PMT825004F Wickmann / Littelfuse	GDT 250V 20KA 3 POLE TH	0
	SL1024A420RF Wickmann / Littelfuse	GDT 420V 10KA 3 POLE TH	0
	SL1021B150RS Wickmann / Littelfuse	GDT 150V 20KA 3 POLE TH	0
	SL1024B260R Wickmann / Littelfuse	GDT 260V 20KA 3 POLE TH	0
	PMT3(310)40004 Wickmann / Littelfuse	GDT 400V 20KA 3 POLE TH	0
	LT350SM Wickmann / Littelfuse	GDT 350V 2 POLE SURFACE MOUNT	0
	SL1024B230RG Wickmann / Littelfuse	GDT 230V 20KA 3 POLE TH	0
	VS800A-B Wickmann / Littelfuse	GDT 800V 1KA 2 POLE THROUGH HOLE	0
	SL1024A300R Wickmann / Littelfuse	GDT 300V 10KA 3 POLE TH	0

Gas Discharge Tube Arresters (GDT)

1. Overview

Gas Discharge Tube Arresters (GDT) are voltage-dependent overvoltage protection devices that utilize ionization of gas to divert high-voltage transients to ground. They act as switches that remain non-conductive under normal operating conditions but rapidly transition to a low-impedance state when voltage exceeds a specific threshold. GDTs play a critical role in safeguarding electronic systems from lightning strikes, electrostatic discharge (ESD), and other transient voltage events in telecommunications, power distribution, and industrial automation systems.

2. Main Types and Functional Classification

Type	Functional Characteristics	Application Examples
Single-Electrode GDT	Compact design with one gas chamber, suitable for low-energy transients	Consumer electronics, IoT devices
Multi-Electrode GDT	Stacked electrodes for higher energy absorption and multi-stage protection	Telecom infrastructure, 5G base stations
Inert Gas GDT	Uses argon/neon for stable performance in harsh environments	Industrial control systems, aerospace
Metal Vapor GDT	Mercury/xenon vapor for ultra-fast response times	High-speed data lines, medical imaging equipment

3. Structure and Components

Typical GDT construction includes:

Ceramic or glass cylindrical body with hermetic sealing
Tungsten/copper alloy electrodes with precision spacing
Inert gas (e.g., argon, neon) or metal vapor filling
External insulation coating (epoxy/silicone rubber)
Threaded/metallic base for grounding connection

4. Key Technical Specifications

Parameter	Typical Range	Importance
DC Spark-over Voltage	70V 5kV	Determines trigger threshold
Impulse Spark-over Voltage	100V 10kV	Response under fast transients
Max Discharge Current	10kA 100kA	Overload handling capability
Response Time	0.1 s 1 s	Critical for ESD protection
Dielectric Strength	1kV 20kV/mm	Post-event insulation recovery

5. Application Fields

Major industry applications include:

Telecommunications: DSL modems, fiber optic transceivers, antenna protection
Industrial Automation: PLC systems, motor drives, sensor networks
Renewable Energy: Solar inverter DC inputs, wind turbine control cabinets
Railway Systems: Signaling equipment, traction converter protection
Case Study: 5G Base Station Implementation

Multi-electrode GDTs protect RF front-end modules from lightning surges
Combined with TVS diodes for multi-level protection architecture
Reduces maintenance costs by 40% in coastal deployments

6. Leading Manufacturers and Products

Manufacturer	Product Series	Key Features
Littelfuse	SPA-GDT Series	Hybrid gas-silicon integration, 10kA rating
Bourns	2021 Series	Surface-mount design, 500V breakdown
Eaton	Pulsar GDT	100kA max current, UL94 certified
Murata	MA48 Series	Nano-coated ceramic body, -55 C~125 C operation

7. Selection Guidelines

Key considerations for GDT selection:

Match breakdown voltage to system operating voltage (min. 1.2x nominal)
Verify discharge current rating exceeds maximum expected surge (IEC 61643-11 compliance)
Consider environmental factors (temperature, humidity, vibration)
Assess mounting requirements (through-hole vs surface-mount)
Coordinate with downstream protection devices for coordinated clamping
Check certification standards (UL, CSA, RoHS)

8. Industry Trends

Future development directions:

Miniaturization for high-density PCB applications (sub-5mm diameters)
Advanced nanogap technologies for sub-nanosecond response times
Integration with AI-based predictive maintenance systems
Development of eco-friendly alternative gases to replace SF6
Wide bandgap semiconductor hybrid protection devices
Increased adoption in EV charging infrastructure (DC fast chargers)