TVS - Varistors, MOVs

Part Number	Description / PDF	Quantity
VAR-18107218M3P-XK TDK Corporation	VARISTOR 21.8V RING SURFACE ELEC	0
AVRL061E1R1NTA TDK Corporation	VARISTOR 39V 0201	11176
AVRM0603C080MT101N TDK Corporation	VARISTOR 8V 4A 0201	1596
VAR-18085115M3P-XK TDK Corporation	VARISTOR 11.5V RING SURFACE ELEC	51
AVRH10C101KT1R1NE8 TDK Corporation	AEC-Q200, ETHERNET, 100V, 1.1PF,	55869
AVRM0603C6R8NT331N TDK Corporation	VARISTOR 6.8V 16A 0201	0
AVRM0603C200MT150N TDK Corporation	VARISTOR 20V 1A 0201	14865
VAR-18086115M3S-XK TDK Corporation	VARISTOR 11.5V RING SIDE ELECT	90
AVRL161A1R1NTA TDK Corporation	VARISTOR 90V 0603	1985
VAR-18086077M3S-XK TDK Corporation	VARISTOR 7.65V RING SIDE ELECT	68
AVRL101A1R1NTA TDK Corporation	VARISTOR 90V 0402	7151
AVR-M1608C270MTAAB TDK Corporation	VARISTOR 27V 2A 0603	92173
AVRH10C101KT4R7FA8 TDK Corporation	VARISTOR 100V 1A 0402	73149
AVR-M1608C270KT2AB TDK Corporation	VARISTOR 27V 20A 0603	10030
AVR-M1608C180MT6AB TDK Corporation	VARISTOR 18V 30A 0603	3322
AVRL161A3R3FTA TDK Corporation	VARISTOR 27V 0603	54169
AVRL161A1R1NTB TDK Corporation	VARISTOR 39V 0603	4781
VAR-18094218M3P-XK TDK Corporation	VARISTOR 21.8V RING SURFACE ELEC	64
AVRM1005C6R8NT101N TDK Corporation	VARISTOR 6.8V 10A 0402	13055
AVRL161D6R8GTA TDK Corporation	COMMERCIAL GRADE MULTILAYER CHIP	6688

TVS - Varistors, MOVs

1. Overview

Transient Voltage Suppressors (TVS), Varistors, and Metal Oxide Varistors (MOVs) are critical components for protecting electronic circuits from voltage spikes and electrostatic discharge (ESD). These devices clamp excessive voltage to safe levels, preventing damage to sensitive components. TVS diodes are semiconductor-based solutions with fast response times, while Varistors (including MOVs) use nonlinear resistive materials to absorb energy. Their importance spans industries like telecommunications, automotive, and consumer electronics, ensuring reliability in environments exposed to electrical surges.

2. Main Types and Functional Classification

Type	Functional Characteristics	Application Examples
TVS Diodes	Unidirectional/bidirectional clamping, sub-nanosecond response time, low leakage current	Communication interfaces (USB, HDMI), microcontrollers, power supplies
Zinc Oxide Varistors	High energy absorption, voltage-dependent resistance, aging characteristics	Power line protection, industrial motor drives, surge protection strips
MOVs	Specialized varistors with metal oxide ceramics, optimized for AC/DC applications	Appliances, LED lighting, renewable energy systems

3. Structure and Composition

TVS diodes employ a PN junction semiconductor structure with doping profiles optimized for breakdown characteristics. Varistors consist of polycrystalline ceramic materials (typically zinc oxide grains with additives) sandwiched between metal electrodes, encapsulated in epoxy or molded housings. MOVs use similar materials to varistors but with enhanced grain boundary engineering for improved voltage clamping. All devices incorporate termination coatings (e.g., silver, tin) for PCB mounting compatibility.

4. Key Technical Parameters

Parameter	Description	Importance
Clamping Voltage (V_CLAMP)	Voltage level during surge conduction	Determines protection level for downstream components
Response Time	Time to transition from blocking to clamping mode	TVS: 0.5-10 ns; MOVs: 10-50 ns
Energy Absorption (W_ADM)	Maximum surge energy handling capability	Measured in joules (J), critical for industrial applications
Leakage Current	Off-state current at rated voltage	Impacts power efficiency, typically <100 A

5. Application Fields

Key industries include:

Consumer Electronics: Smartphone charging circuits, TV power supplies
Industrial Automation: PLCs, motor drives, sensor interfaces
Automotive: ECU protection, CAN bus interfaces, battery management systems
Renewable Energy: Solar inverters, wind turbine controllers

Case Study: MOVs in smart meters provide 10kA surge protection against grid transients.

6. Leading Manufacturers and Products

Manufacturer	Representative Product	Key Specifications
Littelfuse	SM712-02	12A, 13.3V clamping, bidirectional TVS for RS-485
Bourns	V14450A	14mm MOV, 450VAC, 210J energy rating
STMicroelectronics	TV05C060	0.5W, 6V, ultra-small TVS for IoT devices

7. Selection Guidelines

Key considerations:

Operating voltage vs. clamping voltage margin
Surge current requirements (8/20 s waveform standard)
Package size constraints (SMD vs. through-hole)
Environmental conditions (temperature, humidity)
Lifespan expectations (MOVs degrade with repeated surges)

8. Industry Trends

Emerging trends include:

Miniaturization: Sub-0201 TVS devices for mobile applications
Higher energy density: MOVs with >1000J/cm absorption
Integration: Combined ESD and surge protection solutions
Automotive focus: AEC-Q qualified devices for 48V systems
Green manufacturing: Lead-free and RoHS-compliant materials