TVS - Varistors, MOVs

Part Number	Description / PDF	Quantity
ZV130K2220T501N Stackpole Electronics, Inc.	VARISTOR 205V 300A 2220	0
ZV25K1206T201N Stackpole Electronics, Inc.	VARISTOR 39V 200A 1206	0
PV300K3225T Stackpole Electronics, Inc.	VARISTOR 470V 400A 2SMD JLEAD	2337000
ZV35K1210T251N Stackpole Electronics, Inc.	VARISTOR 56V 250A 1210	1164
PV150K3225T Stackpole Electronics, Inc.	VARISTOR 240V 400A 2SMD JLEAD	721
ZV20K1206T201N Stackpole Electronics, Inc.	VARISTOR 33V 200A 1206	0
RV241K07T Stackpole Electronics, Inc.	VARISTOR 240V 1.2KA DISC 7MM	0
RV511K07T Stackpole Electronics, Inc.	VARISTOR 510V 1.2KA DISC 7MM	0
RV681K14T Stackpole Electronics, Inc.	VARISTOR 680V 4.5KA DISC 14MM	0
ZV35K2220T102N Stackpole Electronics, Inc.	VARISTOR 56V 1KA 2220	0
RV241K10T Stackpole Electronics, Inc.	VARISTOR 240V 2.5KA DISC 10MM	0
ZV60K2220T801N Stackpole Electronics, Inc.	VARISTOR 100V 800A 2220	0
RV821K10T Stackpole Electronics, Inc.	VARISTOR 820V 2.5KA DISC 10MM	0
ZV14K1210T401N Stackpole Electronics, Inc.	VARISTOR 22V 400A 1210	0
RV471K05T Stackpole Electronics, Inc.	VARISTOR 470V 400A DISC 5MM	0
RV431K10T Stackpole Electronics, Inc.	VARISTOR 430V 2.5KA DISC 10MM	0
PV275K3225T Stackpole Electronics, Inc.	VARISTOR 430V 400A 2SMD JLEAD	3001
RV391K07T Stackpole Electronics, Inc.	VARISTOR 390V 1.2KA DISC 7MM	0
RV431K14T Stackpole Electronics, Inc.	VARISTOR 430V 4.5KA DISC 14MM	279
ZV30K1210T301N Stackpole Electronics, Inc.	VARISTOR 47V 300A 1210	2500

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