Gas Discharge Tube Arresters (GDT)

Part Number	Description / PDF	Quantity
2036-30-AF J.W. Miller / Bourns	GDT 300V 10KA 3 POLE	0
2038-35-SM J.W. Miller / Bourns	GDT 350V 5KA 3 POLE SMD	0
B88069X9190B252 TDK EPCOS	GDT 350V 10KA 3 POLE TH	0
2027-40-SM-RP J.W. Miller / Bourns	GDT 400V 10KA 2 POLE SMD	0
2026-42-CLF J.W. Miller / Bourns	GDT 420V 20KA 3 POLE TH	0
2056-42-ALF J.W. Miller / Bourns	GDT 420V 5KA 3 POLE	0
GTCN25-900M-R02 Wickmann / Littelfuse	GDT 90V 2.5KA 2 POLE	0
CG21000L Wickmann / Littelfuse	GDT 1000V 10KA 2 POLE TH	449
SL1021B500C Wickmann / Littelfuse	GDT 500V 20KA 3 POLE	0
SL1021B260R Wickmann / Littelfuse	GDT 260V 20KA 3 POLE TH	0
CG43.0SM Wickmann / Littelfuse	GDT 3000V 3KA 2 POLE SMD	1651
B88069X7230B102 TDK EPCOS	GDT 650V 20KA 3 POLE TH	0
2026-15-A1LF J.W. Miller / Bourns	GDT 150V 20KA 3 POLE	0
2027-20-BLF J.W. Miller / Bourns	GDT 200V 10KA 2 POLE TH	0
2051-20-SM-RPLF J.W. Miller / Bourns	GDT 200V 2KA 2 POLE SMD	3249
GTCA38-900M-R10 Wickmann / Littelfuse	GDT 90V 10KA 3 POLE THROUGH HOLE	2000
CG21000MSTR Wickmann / Littelfuse	GDT 1000V 10KA 2 POLE SMD	0
GTCS23-401M-R01-2 Wickmann / Littelfuse	GDT 400V 1KA 2 POLE SMD	0
GTCT38-401M-R20 Wickmann / Littelfuse	GDT 400V 20KA 3 POLE TH	0
CG2230LTR Wickmann / Littelfuse	GDT 230V 20KA 2 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)