TVS - Varistors, MOVs

Part Number	Description / PDF	Quantity
EZJ-P0V650DM Panasonic	VARISTOR 65V 2A 0402	5240
EZJ-ZSV270CAK Panasonic	VARISTOR 27V 5A 0504	7676
ERZ-E10E112 Panasonic	VARISTOR 1.1KV 4.5KA DISC	0
ERZ-C20EK391Y Panasonic	VARISTOR 390V 8KA MODULE	25
ERZ-C32EK271Y Panasonic	VARISTOR 270V 25KA MODULE	49
ERZ-V05D121 Panasonic	VARISTOR 120V 800A DISC 5MM	0
ERZ-E11A221 Panasonic	VARISTOR 220V 6KA DISC 13MM	1907
ERZ-E10E751 Panasonic	VARISTOR 750V 4.5KA DISC 12.50MM	0
ERZ-E14A621 Panasonic	VARISTOR 620V 7.5KA DISC 17.5MM	0
ERZ-E05A221CS Panasonic	VARISTOR 220V 1.2KA DISC 7MM	0
ERZ-C32EK201 Panasonic	VARISTOR 200V 25KA MODULE	65
ERZ-C32CK621B Panasonic	VARISTOR 620V 25KA DISC 32MM	264
ERZ-V10D201 Panasonic	VARISTOR 200V 3.5KA DISC 10MM	1306
ERZ-U31JP252H Panasonic	DELTATRANSIENT/SURGE ABSORBERS10	1
EZJ-ZSV270DAK Panasonic	VARISTOR 27V 5A 0504	6072
EZJ-P0V270GM Panasonic	VARISTOR 27V 10A 0402	9142
ERZ-VS34C361 Panasonic	VARISTOR 360V 40KA SQUARE 36MM	19
ERZ-V07D221 Panasonic	VARISTOR 220V 1.75KA DISC 7MM	3790
ERZ-V14D820 Panasonic	VARISTOR 82V 6KA DISC 14MM	11951
ERZ-E14A241S1 Panasonic	VARISTOR DISC 14MM 240V	1334

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