TVS - Varistors, MOVs

Part Number	Description / PDF	Quantity
ERZ-V10D911 Panasonic	VARISTOR 910V 3.5KA DISC 10MM	2973
ERZ-C20EK361Y Panasonic	VARISTOR 360V 8KA MODULE	0
ERZ-E10B102CS Panasonic	VARISTOR 1KV 4.5KA DISC 12.50MM	0
ERZ-V20D331 Panasonic	VARISTOR 330V 10KA DISC 20MM	814
EZJ-Z1V270EA Panasonic	VARISTOR 27V 20A 0603	3860
ERZ-U32JP252F Panasonic	SINGLETRANSIENT/SURGE ABSORBERS1	1
ERZ-C32EK391Y Panasonic	VARISTOR 390V 25KA MODULE	10
ERZ-E10A511CS Panasonic	VARISTOR 510V 4.5KA DISC 11.5MM	0
ERZ-U16JP511 Panasonic	SINGLETRANSIENT/SURGE ABSORBERS1	1
ERZ-E10E911 Panasonic	VARISTOR 910V 4.5KA DISC 12.50MM	0
ERZ-C32EK821Y Panasonic	VARISTOR 820V 25KA MODULE	2
ERZ-U13JP511 Panasonic	SINGLETRANSIENT/SURGE ABSORBERS1	1
ERZ-E05A391CS Panasonic	VARISTOR 390V 1.2KA DISC 7MM	0
ERZ-V09D390 Panasonic	VARISTOR 39V 1KA DISC 10MM	0
ERZ-V10D820 Panasonic	VARISTOR 82V 3.5KA DISC 10MM	0
EZJ-Z0V650DA Panasonic	VARISTOR 65V 5A 0402	12141
ERZ-C40CK361B Panasonic	VARISTOR 360V 30KA DISC 40MM	0
ERZ-C40CK821B Panasonic	VARISTOR 820V 30KA DISC 40MM	0
ERZ-U12JP511 Panasonic	SINGLETRANSIENT/SURGE ABSORBERS1	1
ERZ-V10D270 Panasonic	VARISTOR 27V 1KA DISC 10MM	1430

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