TVS - Varistors, MOVs

Part Number	Description / PDF	Quantity
ERZ-V14D680 Panasonic	VARISTOR 68V 2KA DISC 14MM	26628
ERZ-E05A331 Panasonic	VARISTOR 330V 1.2KA DISC 7MM	502
ERZ-V05D470 Panasonic	VARISTOR 47V 250A DISC 5MM	9141
ERZ-E14A271S1 Panasonic	VARISTOR DISC 14MM 270V	0
ERZ-E05A431CS Panasonic	VARISTOR 430V 1.2KA DISC 7MM	0
ERZ-V14D560 Panasonic	VARISTOR 56V 2KA DISC 14MM	2496
EZJ-P1V270RM Panasonic	VARISTOR 27V 2A 0603	6840
ERZ-E07A221 Panasonic	VARISTOR 220V 2.5KA DISC 9MM	2762
ERZ-E08A621 Panasonic	VARISTOR 620V 3.5KA DISC 11.5MM	43
ERZ-C32EK911Y Panasonic	VARISTOR 910V 25KA MODULE	44
ERZ-E14A221 Panasonic	VARISTOR 220V 10KA DISC 16.5MM	1042
ERZ-E11A201 Panasonic	VARISTOR 200V 6KA DISC 13MM	2832
ERZ-E08A681CS Panasonic	VARISTOR 680V 3.5KA DISC 11.5MM	0
ERZ-E11A361CS Panasonic	VARISTOR 360V 6KA DISC 13MM	0
ERZ-U25JP162F Panasonic	SINGLETRANSIENT/SURGE ABSORBERS1	1
ERZ-VF2M101 Panasonic	VARISTOR 100V 600A 2SMD JLEAD	0
EZJ-P1V120KA Panasonic	VARISTOR 12V 330PF 0603	1160
ERZ-E10F102 Panasonic	VARISTOR 1KV 4.5KA DISC 12.50MM	0
ERZ-VF2M221 Panasonic	VARISTOR 220V 600A 2SMD JLEAD	10617
ERZ-C40CK391B Panasonic	VARISTOR 390V 30KA DISC 40MM	0

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