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When specifying surge protection for electrical systems, engineers face a fundamental choice among three core technologies: Metal Oxide Varistor (MOV), Gas Discharge Tube (GDT), and Transient Voltage Suppressor (TVS) diode. Each technology offers distinct performance characteristics rooted in different physical principles—MOVs harness nonlinear ceramic resistance, GDTs exploit gas ionization, and TVS diodes leverage semiconductor avalanche breakdown.
The selection isn’t about finding the “best” technology. Rather, it’s about matching fundamental trade-offs to application requirements. A MOV that excels in AC mains distribution may fail catastrophically on a high-speed data line. A GDT perfect for telecom interfaces would be wrong for a 5V DC supply rail. A TVS diode ideal for board-level I/O might be overwhelmed on a lightning-exposed outdoor circuit.
This article examines each technology from first principles, explains the physics behind their performance differences, and provides quantified comparison across response time, clamping voltage, energy handling, capacitance, aging behavior, and cost. Whether you’re designing a power distribution SPD, protecting communication interfaces, or coordinating multi-stage protection, understanding these fundamental differences will help you select components that actually protect—not just pass procurement.
Figure 0: Physical comparison of three surge protection technologies. Left: MOV (Metal Oxide Varistor) shows characteristic blue zinc oxide ceramic disk with radial leads—physical size scales with voltage rating (disk thickness) and current capacity (disk diameter). Center: GDT (Gas Discharge Tube) displays cylindrical sealed glass/ceramic envelope containing inert gas and electrodes—hermetic construction ensures stable sparkover characteristics. Right: TVS Diode demonstrates various semiconductor packages from compact SMD (0402, SOT-23) to larger through-hole formats (DO-201, DO-218)—silicon die size determines pulse power rating. The stark physical differences reflect fundamentally different operating principles: ceramic grain-boundary junctions (MOV), gas ionization plasma (GDT), and semiconductor avalanche breakdown (TVS).
MOV (Metal Oxide Varistor): Structure and Operating Principle
The Metal Oxide Varistor is a ceramic semiconductor device whose resistance drops dramatically as voltage increases. This voltage-dependent behavior makes it act like an automatic voltage clamp—conducting heavily during surges while remaining nearly invisible during normal operation.
Internal Architecture
A MOV consists of zinc oxide (ZnO) grains sintered together with small amounts of bismuth, cobalt, manganese, and other metal oxides. The magic happens at the grain boundaries. Each boundary between adjacent ZnO grains forms a microscopic Schottky barrier—essentially a tiny back-to-back diode junction. A single MOV disk contains millions of these micro-junctions connected in a complex three-dimensional series-parallel network.
The device’s bulk properties emerge from this microstructure. Disk thickness determines operating voltage (more grain boundaries in series = higher voltage rating). Disk diameter determines current capability (more parallel paths = higher surge current). This is why MOV datasheets specify varistor voltage per millimeter of thickness and why high-energy MOVs for power distribution are physically large block or disk assemblies.
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At voltages below the varistor voltage (Vᵥ), the grain-boundary junctions remain in depletion mode and the device draws only microampere-level leakage current. When a surge drives voltage above Vᵥ, the junctions break down via quantum tunneling and avalanche multiplication. Resistance collapses from megohms to ohms, and the MOV shunts surge current to ground.
This transition is intrinsically fast—sub-nanosecond at the material level. Standard catalog MOVs achieve response times below 25 nanoseconds, limited primarily by lead inductance and package geometry rather than the ZnO physics. The voltage-current characteristic is highly nonlinear, typically described by the equation I = K·Vᵅ where the nonlinearity coefficient α ranges from 25 to 50 (compared to α = 1 for a linear resistor).
Key Specifications and Behavior
Energy Handling: MOVs excel at absorbing surge energy. Manufacturers rate energy capability using 2-millisecond rectangular pulses and surge current using the standard 8/20 µs waveform. Block MOVs for power distribution can handle 10,000 to 100,000 amperes of surge current in single events.
Aging and Degradation: Repeated surge exposure causes cumulative microstructural damage. The varistor voltage shifts downward, leakage current increases, and clamping performance degrades. Heavy overloads can puncture grain boundaries, creating permanent conductive paths. For this reason, datasheets specify derating factors for repetitive surges, and critical installations should monitor MOV leakage current as a maintenance parameter.
ຄໍາຮ້ອງສະຫມັກທົ່ວໄປ: AC mains surge protection, power distribution panels, industrial motor drives, heavy equipment, and any application requiring high energy absorption with fast (nanosecond) response.
Figure 1: MOV cutaway section showing zinc oxide (ZnO) grains embedded in ceramic matrix with inter-granular boundaries (magnified inset). Each grain boundary forms a microscopic Schottky barrier, creating millions of micro-junctions in series-parallel configuration. The disk’s physical dimensions—thickness determines voltage rating (more boundaries in series), diameter determines current capability (more parallel paths)—directly control surge protection performance.
GDT (Gas Discharge Tube): Structure and Operating Principle
The Gas Discharge Tube takes a fundamentally different approach: instead of clamping voltage with nonlinear resistance, it creates a temporary short circuit when voltage exceeds a threshold. This “crowbar” action diverts surge current through ionized gas rather than solid-state materials.
Internal Architecture
A GDT consists of two or three electrodes sealed inside a ceramic or glass envelope filled with inert gas (typically a mixture of argon, neon, or xenon at sub-atmospheric pressure). The electrode gap and gas composition determine the breakdown voltage. The hermetic seal is critical—any contamination or pressure change would alter breakdown characteristics.
Three-electrode GDTs are common in telecom applications, providing line-to-line and line-to-ground protection in a single component. Two-electrode versions serve simpler line-to-ground configurations. The electrodes are often coated with materials that reduce the breakdown voltage and stabilize arc formation.
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Under normal conditions, the gas is non-conductive and the GDT presents near-infinite impedance (>10⁹ Ω) with extremely low capacitance—typically below 2 picofarads. When a transient voltage exceeds the spark-over voltage, the electric field ionizes the gas. Free electrons accelerate and collide with gas atoms, liberating more electrons in an avalanche process. Within a fraction of a microsecond, a conductive plasma channel forms between electrodes.
Once ionized, the GDT enters arc mode. Voltage across the device collapses to a low arc voltage—typically 10-20 volts regardless of the initial breakdown voltage. The device now acts as a near-short, diverting surge current through the plasma. The arc persists until current drops below the “glow-to-arc transition current,” typically tens of milliamperes.
This crowbar behavior creates a critical design consideration: if the protected circuit can source sufficient “follow current” above the glow threshold, the GDT may latch in conduction even after the transient ends. This is why GDTs on AC mains require series resistance or coordination with upstream breakers. On low-impedance DC supplies, follow-current latching can be catastrophic.
Key Specifications and Behavior
Surge Current Capability: GDTs handle extremely high surge currents—typical telecom-grade devices are rated for 10,000 to 20,000 amperes (8/20 µs waveform) with multi-shot endurance. This high capacity comes from the distributed nature of the plasma channel rather than localized solid-state junctions.
Capacitance: The defining advantage of GDTs is their sub-2 pF capacitance, making them transparent to high-speed signals. This is why they dominate telecom line protection: xDSL, cable broadband, and Gigabit Ethernet can’t tolerate the capacitance of MOVs or many TVS devices.
ເວລາຕອບສະຫນອງ: GDTs are slower than solid-state devices. Breakdown typically occurs within hundreds of nanoseconds to a few microseconds, depending on the voltage overshoot (higher dV/dt accelerates ionization). For fast transients on sensitive electronics, GDTs are often paired with faster clamps in a coordinated protection scheme.
Stability and Lifespan: Quality GDTs exhibit excellent long-term stability. ITU-T K.12 and IEEE C62.31 test methods verify performance over thousands of surge cycles. UL-recognized telecom GDTs demonstrate minimal parameter shift over decades of service.
ຄໍາຮ້ອງສະຫມັກທົ່ວໄປ: Telecom line protection (xDSL, cable, fiber optics), high-speed Ethernet interfaces, RF and antenna inputs, and any application where minimal line loading is essential and the surge source impedance is high enough to prevent follow-current latching.
Figure 2: Gas Discharge Tube (GDT) construction and operating behavior. Left diagram shows internal structure: hermetically sealed gas chamber with electrode gap and inert gas fill (argon/neon). Right graph illustrates ionization response—when transient voltage exceeds spark-over threshold, gas ionizes creating conductive plasma channel, voltage collapses to arc mode (~10-20V), and surge current diverts through the plasma until current drops below glow-to-arc transition threshold.
TVS Diode: Structure and Operating Principle
Transient Voltage Suppressor diodes are silicon avalanche devices engineered specifically for surge clamping. They combine the fastest response times with the lowest clamping voltages available in surge protection components, making them the preferred choice for protecting sensitive semiconductor circuits.
Internal Architecture
A TVS diode is essentially a specialized Zener diode optimized for high pulse power rather than voltage regulation. The silicon die features a heavily doped P-N junction designed to enter avalanche breakdown at a precise voltage. Die area is much larger than equivalent Zener regulators to handle the peak currents of surge events—hundreds of amperes in submicrosecond pulses.
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Under normal operating voltage, the TVS diode operates in reverse bias with only nanoampere-level leakage. When a transient exceeds the reverse breakdown voltage (V_BR), the silicon junction enters avalanche multiplication. Impact ionization generates a flood of electron-hole pairs, and junction resistance collapses. The device clamps voltage at the breakdown level plus the dynamic resistance times the surge current.
The physics is purely solid-state with no mechanical motion, gas ionization, or material phase change. This enables response times in the nanosecond range—sub-1 ns for the bare silicon, though package inductance typically pushes effective response to 1-5 ns for practical devices. The voltage-current characteristic is very steep (low dynamic resistance), providing tight clamping.
Key Specifications and Behavior
Pulse Power Ratings: TVS manufacturers specify power capacity using standardized pulse widths (typically 10/1000 µs exponential waveforms). Common product families offer 400W, 600W, 1500W, or 5000W pulse ratings. Peak current capability is calculated from pulse power and clamping voltage—a 600W device with 15V clamp handles about 40A peak.
Clamping Performance: TVS diodes offer the lowest clamping voltages of any surge protection technology. The ratio of clamping voltage to standoff voltage (V_C/V_WM) is typically 1.3 to 1.5, compared to 2.0-2.5 for MOVs. This tight control is critical for protecting 3.3V logic, 5V USB, 12V automotive circuits, and other voltage-sensitive loads.
Capacitance: TVS capacitance varies widely with device construction. Standard junction TVS diodes can exhibit hundreds of picofarads, which loads high-speed data lines. Low-capacitance TVS families engineered for HDMI, USB 3.0, Ethernet, and RF use specialized junction geometries and achieve sub-5 pF per line.
Aging and Reliability: Unlike MOVs, TVS diodes exhibit minimal performance drift under rated pulse stress. The silicon junction doesn’t degrade cumulatively from repeated surges within ratings. Failure modes are typically open-circuit (junction annihilation) or short-circuit (metallization fusing), both of which occur only under extreme overload well beyond ratings.
ຄໍາຮ້ອງສະຫມັກທົ່ວໄປ: Board-level circuit protection (I/O ports, power rails), USB and HDMI interfaces, automotive electronics, DC power supplies, communication data lines, and any application requiring fast response and tight voltage clamping for semiconductor loads.
Figure 3: TVS diode voltage-current (I-V) characteristic curve showing semiconductor avalanche operation. Under normal voltage (V_WM standoff region), device maintains high impedance with nanoampere leakage. When transient exceeds reverse breakdown voltage (V_BR), silicon P-N junction enters avalanche multiplication—junction resistance collapses and device clamps voltage at V_C (breakdown voltage plus dynamic resistance × surge current). The steep curve (low dynamic resistance) provides tight voltage control critical for protecting semiconductor loads.
Clamping vs Crowbar: Two Protection Philosophies
The fundamental difference between these technologies lies in their protection philosophy. MOVs and TVS diodes are clamping devices—they limit voltage to a specific level proportional to surge current. GDTs are crowbar devices—they create a short circuit that collapses voltage to a low residual level regardless of current magnitude.
Clamping behavior (MOV and TVS): As surge current increases, clamping voltage rises according to the device’s nonlinear V-I curve. A MOV rated 275V RMS might clamp at 750V for a 1 kA surge but rise to 900V at 5 kA. A TVS diode rated 15V standoff might clamp at 24V for 10A but reach 26V at 20A. The protected load sees a voltage determined by surge amplitude and device characteristics.
Crowbar behavior (GDT): Once breakdown occurs, the GDT enters arc mode and voltage collapses to 10-20V regardless of whether surge current is 100A or 10,000A. This provides excellent protection once triggered, but the initial spark-over can allow a voltage spike before ionization completes. This is why sensitive loads behind GDTs often need a secondary fast clamp.
Each philosophy suits different applications. Clamping devices protect by limiting voltage exposure. Crowbar devices protect by diverting current. Clamping works when the protected circuit can tolerate the clamp voltage. Crowbar works when the surge source has high enough impedance that shorting the line doesn’t damage upstream equipment or cause follow-current problems.
MOV vs GDT vs TVS: Side-by-Side Comparison
The table below quantifies the key performance differences across these three surge protection technologies:
| ພາລາມິເຕີ | MOV (Metal Oxide Varistor) | GDT (Gas Discharge Tube) | TVS Diode |
| ຫຼັກການປະຕິບັດງານ | Voltage-dependent nonlinear resistance (ZnO grain boundaries) | Gas ionization crowbar | Semiconductor avalanche breakdown |
| ກົນໄກການປົກປ້ອງ | Clamping | Crowbar | Clamping |
| ເວລາຕອບສະຫນອງ | <25 ns (typical catalog parts) | 100 ns – 1 µs (voltage-dependent) | 1-5 ns (package-limited) |
| Clamping/Arc Voltage | 2.0-2.5 × MCOV | 10-20 V (arc mode) | 1.3-1.5 × V_standoff |
| Surge Current (8/20 µs) | 400 A – 100 kA (size-dependent) | 5 kA – 20 kA (telecom-grade) | 10 A – 200 A (600W family ~40A) |
| Energy Handling | Excellent (100-1000 J) | Excellent (distributed plasma) | Moderate (limited by junction) |
| Capacitance | 50-5000 pF (area-dependent) | <2 pF | 5-500 pF (construction-dependent) |
| Aging Behavior | Degrades with surge cycles; V_n drifts down | Stable over thousands of surges | Minimal drift within ratings |
| Failure Mode | Degradation → short or open | Short (arc sustaining) | Open or short (catastrophic only) |
| Follow-Current Risk | Low (self-extinguishing) | High (requires external limiting) | None (solid-state) |
| Typical Voltage Range | 18V RMS – 1000V RMS | 75V – 5000V DC sparkover | 3.3V – 600V standoff |
| Cost (Relative) | Low ($0.10 – $5) | Low-Medium ($0.50 – $10) | Low-Medium ($0.20 – $8) |
| ມາດຕະຖານ | IEC 61643-11, UL 1449 | ITU-T K.12, IEEE C62.31 | IEC 61643-11, UL 1449 |
| ຖອງ | AC mains, power distribution, industrial | Telecom lines, high-speed data, antenna | Board-level I/O, DC supplies, automotive |
Key Takeaways from the Comparison
MOVs offer the best balance of energy handling, fast response, and cost for power-level surges. They dominate AC mains protection but suffer from capacitance loading on high-frequency circuits and cumulative aging under repeated stress.
GDTs excel where minimal line loading is critical and surge current capability must be maximized. Their ultra-low capacitance makes them irreplaceable in telecom and RF applications, but slower response and follow-current risk require careful circuit design.
TVS diodes provide the fastest, tightest clamping for sensitive electronics. They are the only practical choice for protecting semiconductor I/O at voltages below 50V, but limited energy capacity means they can’t handle the lightning-level surges that MOVs and GDTs routinely absorb.
Figure 4: Professional comparison chart contrasting MOV (Metal Oxide Varistor) and TVS (Transient Voltage Suppressor) technologies across key specifications. MOVs exhibit higher clamping voltage ratios (2.0-2.5× MCOV) with excellent energy absorption for power-level surges, while TVS diodes deliver tighter voltage control (1.3-1.5× standoff) with faster response (<5 ns) for semiconductor protection. The table includes voltage ratings, surge current capabilities, and typical part number examples demonstrating the complementary performance envelopes of each technology.
Technology Selection Guide: When to Use Each
Choosing the right surge protection technology depends on matching device characteristics to circuit requirements. Here’s a decision framework:
Use MOV When:
- Circuit voltage is AC mains or high-voltage DC (>50V): MOVs are available in voltage ratings from 18V RMS to over 1000V, perfectly matching residential (120/240V), commercial (277/480V), and industrial power distribution.
- Surge energy is high: Lightning-induced surges, utility switching transients, and motor inrush produce energy levels (hundreds to thousands of joules) that only MOVs can absorb economically.
- Response time <25 ns is acceptable: Most power electronics and industrial equipment tolerate MOV response speed.
- Capacitance loading is acceptable: At power frequencies (50/60 Hz), even 1000 pF capacitance is negligible.
- Cost is constrained: MOVs offer the lowest cost per joule of protection.
Avoid MOVs when protecting high-speed communication lines (capacitance loading), low-voltage semiconductor circuits (clamping voltage too high), or applications requiring guaranteed no-drift performance over decades (aging concerns).
Use GDT When:
- Line loading must be minimal (<2 pF): xDSL modems, cable broadband, Gigabit Ethernet, RF receivers, and antenna inputs cannot tolerate the capacitance of MOVs or standard TVS devices.
- Surge current capability must be maximized: Telecom central offices, cell towers, and outdoor installations face repeated high-amplitude lightning surges that exceed TVS ratings.
- Protected circuit has high source impedance: Telephone lines (600Ω), antenna feedlines (50-75Ω), and data cables can safely be crowbarred without excessive follow-current.
- Operating voltage is high (>100V): GDTs are available with sparkover voltages from 75V to 5000V, covering telecom voltages, PoE (Power over Ethernet), and high-voltage signaling.
Avoid GDTs when protecting low-impedance DC power supplies (follow-current risk), circuits requiring fastest response (<100 ns critical), or voltage-sensitive loads that can’t tolerate the initial spark-over spike (needs secondary clamping).
Use TVS Diode When:
- Clamping voltage must be tightly controlled: 3.3V logic, 5V USB, 12V automotive circuits, and other semiconductor loads require clamping within 20-30% of nominal voltage—only TVS diodes deliver this.
- Response time must be fastest (<5 ns): Protecting high-speed processors, FPGAs, and sensitive analog circuits demands nanosecond response.
- Circuit voltage is low to medium (<100V): TVS families cover everything from 3.3V data lines to 48V telecom supplies.
- Aging/drift cannot be tolerated: Medical devices, aerospace, and safety-critical systems require predictable, stable protection over product lifetime.
- Board space is limited: SMT TVS devices in 0402 or SOT-23 packages fit where MOVs and GDTs cannot.
Avoid TVS diodes when surge energy exceeds pulse power rating (typical 600W device absorbs only ~1 joule), surge current exceeds peak rating (40A typical for 600W at 15V), or cost per channel becomes prohibitive in multi-line systems.
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| ຄໍາຮ້ອງສະຫມັກ | Primary Technology | Rationale |
| AC mains panel protection | MOV (Type 1/2 SPD) | High energy, 120-480V, cost-effective |
| Telecom line interface | GDT + TVS (staged) | GDT absorbs energy, TVS clamps residual |
| USB 2.0 / 3.0 data lines | Low-cap TVS | Fast edges, 5V supply, <5 pF required |
| Ethernet (10/100/1000 Base-T) | GDT (primary) + low-cap TVS | Minimal loading, high surge exposure |
| 24V DC industrial I/O | TVS | Tight clamp, fast response, no aging |
| PV solar DC input | MOV (DC-rated) | High voltage (600-1000V), high energy |
| Automotive 12V circuits | TVS | Load dump protection, tight clamp at 24-36V |
| RF antenna input | GDT | Sub-2 pF, high power handling |
| 3.3V FPGA power rail | TVS (low-cap) | 6-8V clamp, <1 ns response critical |
This matrix is a starting point. Complex installations often combine technologies in layered protection schemes, leveraging the strengths of each stage.
Figure 5: Professional three-stage surge protection architecture diagram illustrating coordinated protection strategy. Stage 1 (Primary): Type 1 MOV SPD at service entrance handles extreme surge energy (40-100 kA) and clamps voltage from 10+ kV to ~600V. Stage 2 (Secondary): Gas Discharge Tube diverts residual high-voltage transients and reduces voltage to ~30V through arc mode operation. Stage 3 (Final): TVS diode provides tight clamping (<1.5× standoff voltage) with nanosecond response to protect sensitive semiconductor loads. Each stage features proper grounding and voltage coordination to ensure upstream devices trigger before downstream components, creating clear “handoff” points that distribute surge energy across the protection cascade. This layered approach leverages the complementary strengths of MOV (high energy), GDT (low capacitance), and TVS (tight clamp) technologies.
Layered Protection: Combining Technologies
The most robust surge protection architectures don’t rely on a single technology. Instead, they coordinate multiple stages, each optimized for a different portion of the threat spectrum. This “defense in depth” approach leverages the complementary strengths of MOV, GDT, and TVS technologies.
Why Layer Protection?
Energy distribution: A single TVS diode can’t absorb a 10 kA lightning surge, but a GDT upstream can divert 99% of that energy, leaving the TVS to clamp the residual. Each stage handles what it does best.
Speed optimization: A GDT takes hundreds of nanoseconds to ionize. During that time, a fast TVS downstream can clamp the initial spike, preventing damage to sensitive loads. Once the GDT fires, it takes over bulk current diversion.
Voltage coordination: The upstream device must break down before the downstream device. Proper selection ensures the first stage conducts at, say, 600V, limiting what reaches the second stage (rated 150V), which in turn protects the final load (rated 50V).
Common Layered Architectures
Telecom Interface (GDT + TVS):
- Primary stage: GDT at the interface boundary handles direct lightning strikes and high-voltage power faults (2-10 kV surges, up to 20 kA).
- Secondary stage: Low-capacitance TVS diode clamps residual transients to safe levels for the transceiver IC (<30V).
- ການປະສານງານ: GDT sparkover at 400V, TVS breakdown at 15V, transceiver maximum rating 12V. The TVS protects during GDT ionization delay; once GDT fires, it assumes bulk current duty.
Ethernet PoE (GDT + TVS + Inductor):
- Primary: GDT diverts line-to-ground lightning surges.
- Series inductor: Slows surge rise time (dV/dt), giving GDT time to ionize and limiting current into downstream stages.
- Secondary: TVS diodes on each differential pair clamp common-mode and differential-mode transients to protect the Ethernet PHY (±8V max).
Industrial AC Panel (MOV Primary + MOV Secondary):
- ທາງເຂົ້າບໍລິການ: Type 1 MOV rated 40-100 kA handles direct lightning (1.2/50 µs voltage, 10/350 µs current waveforms per IEC 61643-11).
- Distribution panel: Type 2 MOV rated 20-40 kA clamps residual surges that couple through building wiring.
- Load equipment: Type 3 SPD or board-level TVS provides final point-of-use protection.
PV Solar System (MOV DC + TVS):
- Array junction box: DC-rated MOV (600-1000V) on PV string output handles lightning-induced surges.
- Inverter input: TVS diodes protect DC-DC converter and MPPT controller semiconductors, clamping at levels the silicon can survive.
The key to successful coordination is selecting breakdown voltages that create clear “handoff” points and verifying that let-through energy from one stage remains within the rating of the next stage. Manufacturers of complete SPD systems (like VIOX) often publish tested, coordinated assemblies that eliminate this design complexity.
ສະຫລຸບ
Selecting surge protection components is not about finding the “best” technology—it’s about matching physics to requirements. MOVs leverage zinc oxide ceramics to absorb high energy at power voltages. GDTs exploit gas ionization to achieve minimal line loading with maximum current capability. TVS diodes harness semiconductor avalanche for the fastest, tightest clamping of sensitive electronics.
Each technology represents a fundamental trade-off:
- MOVs trade higher clamping voltage and aging for excellent energy handling and cost.
- GDTs trade slower response and follow-current risk for ultra-low capacitance and surge endurance.
- TVS diodes trade limited energy capacity for fastest response and tightest voltage control.
Understanding these trade-offs—rooted in the operating principles we’ve examined—enables you to specify protection that actually works in your application. A 600V MOV on a 5V data line will fail to protect. A 40A TVS diode facing a 10 kA lightning surge will fail catastrophically. A GDT on a low-impedance DC supply may latch into destructive follow-current conduction.
For complex installations, layered protection coordinates multiple technologies, positioning each where it performs best. The GDT absorbs bulk energy, the MOV handles power-level surges, and the TVS delivers final-stage clamping for semiconductor loads.
Whether you’re designing a power distribution SPD rated for 100 kA per IEC 61643-11, protecting a Gigabit Ethernet interface with sub-2 pF loading, or safeguarding 3.3V FPGA I/O, the decision framework is the same: match device physics to circuit requirements, verify ratings against threat waveforms, and coordinate stages when a single technology can’t cover the full spectrum.
ກ່ຽວກັບ VIOX Electric: As a leading manufacturer of surge protection devices, VIOX offers comprehensive MOV, GDT, and TVS solutions for residential, commercial, and industrial applications. Our engineering team provides application support for coordinated protection systems. Visit www.viox.com or contact our technical sales team for specification assistance.
