TVS - Varistors, MOVs

Part Number	Description / PDF	Quantity
VDRH14V275BSE Vishay BC Components/Beyshlag/Draloric	VARISTOR 430V 6KA DISC 16MM	520
VDRUS14X275BSE Vishay BC Components/Beyshlag/Draloric	VDR US 14D 8000A 275V STLDS BULK	1989
VDRS05C275BSE Vishay BC Components/Beyshlag/Draloric	VARISTOR 430V 400A DISC 7MM	2209
VDRS10D020TSE Vishay BC Components/Beyshlag/Draloric	VARISTOR 33V 500A DISC 12MM	0
VDRS20W140BSE Vishay BC Components/Beyshlag/Draloric	VARISTOR 220V 6.5KA DISC 22.50MM	0
VDRS05C230BSE Vishay BC Components/Beyshlag/Draloric	VARISTOR 360V 400A DISC 7MM	0
VDRS14T060BSE Vishay BC Components/Beyshlag/Draloric	VARISTOR 100V 4.5KA DISC 16MM	0
VDRS14T075BSE Vishay BC Components/Beyshlag/Draloric	VARISTOR 120V 4.5KA DISC 16MM	0
VDRS20W550BSE Vishay BC Components/Beyshlag/Draloric	VARISTOR 910V 6.5KA DISC 23MM	0
VDRUS10T300BSE Vishay BC Components/Beyshlag/Draloric	VDR US 10D 4500A 300V STLDS BULK	945
VDRS20W150BSE Vishay BC Components/Beyshlag/Draloric	VARISTOR 240V 6.5KA DISC 22.50MM	0
VDRS20W275BSE Vishay BC Components/Beyshlag/Draloric	VARISTOR 430V 6.5KA DISC 22.50MM	0
VDRUS10T250BSE Vishay BC Components/Beyshlag/Draloric	VDR US 10D 4500A 250V STLDS BULK	2185
VDRH20X300BKE Vishay BC Components/Beyshlag/Draloric	VARISTOR 470V 10KA DISC 22.50MM	470
VDRS14T300BSE Vishay BC Components/Beyshlag/Draloric	VARISTOR 470V 4.5KA DISC 16MM	714
VDRUS10T510BKE Vishay BC Components/Beyshlag/Draloric	VDR US 10D 4500A 510V KNLDS	0
VDRS20W625BSE Vishay BC Components/Beyshlag/Draloric	VARISTOR 1KV 6.5KA DISC 23MM	0
VDRUS10T320BSE Vishay BC Components/Beyshlag/Draloric	VDR US 10D 4500A 320V STLDS BULK	1905
VDRS10P060BSE Vishay BC Components/Beyshlag/Draloric	VARISTOR 100V 2.5KA DISC 12MM	0
VDRS07H275BSE Vishay BC Components/Beyshlag/Draloric	VARISTOR 430V 1.2KA DISC 9MM	3176

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