TVS - Varistors, MOVs

Part Number	Description / PDF	Quantity
EZJ-P1V270GM Panasonic	VARISTOR 27V 10A 0603	7684
ERZ-C32CK241W Panasonic	VARISTOR 240V 25KA DISC 32MM	0
ERZ-V07D560 Panasonic	VARISTOR 56V 500A DISC 7MM	616
EZJ-Z0V270EA Panasonic	VARISTOR 27V 0402	1459
ERZ-U21JP112B Panasonic	DELTATRANSIENT/SURGE ABSORBERS10	1
ERZ-V10D101 Panasonic	VARISTOR 100V 3.5KA DISC 10MM	0
ERZ-E14A201S1 Panasonic	VARISTOR DISC 14MM 200V	657
ERZ-U14JP541 Panasonic	SINGLETRANSIENT/SURGE ABSORBERS1	1
EZJ-Z1V420FA Panasonic	VARISTOR 42V 15A 0603	19955
ERZ-C32EK102Y Panasonic	VARISTOR 1KV 25KA MODULE	43
ERZ-V14D101 Panasonic	VARISTOR 100V 6KA DISC 14MM	0
ERZ-U17JP511 Panasonic	SINGLETRANSIENT/SURGE ABSORBERS1	1
ERZ-U22JP102 Panasonic	SINGLETRANSIENT/SURGE ABSORBERS1	1
ERZ-V10D681 Panasonic	VARISTOR 680V 3.5KA DISC 10MM	34847
ERZ-V20D681 Panasonic	VARISTOR 680V 7.5KA DISC 20MM	262
ERZ-E07A471CS Panasonic	VARISTOR 470V 2.5KA DISC 9MM	0
ERZ-C40CK431B Panasonic	VARISTOR 430V 30KA DISC 40MM	0
ERZ-VS34C951 Panasonic	VARISTOR 950V 40KA SQUARE 36MM	10
ERZ-V07D470 Panasonic	VARISTOR 47V 500A DISC 7MM	0
ERZ-E07A241 Panasonic	VARISTOR 240V 2.5KA DISC 9MM	688

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