TVS - Varistors, MOVs

Part Number	Description / PDF	Quantity
8S17SM170 Maida Development Company	MOV SURFACE MOUNT CHIP 3220 17VA	10000
8S17SM950 Maida Development Company	MOV SURFACE MOUNT CHIP 3220 95VA	10000
8S17SM301 Maida Development Company	MOV SURFACE MOUNT CHIP 3220 300V	9925
8S17SM300 Maida Development Company	MOV SURFACE MOUNT CHIP 3220 30VA	10000
8S17SM400T6 Maida Development Company	MOV SURFACE MOUNT CHIP 3220 40VA	10000
8S17SM750 Maida Development Company	MOV SURFACE MOUNT CHIP 3220 75VA	10000
8S17SM141T6 Maida Development Company	MOV SURFACE MOUNT CHIP 3220 140V	10000
8S17SM181 Maida Development Company	MOV SURFACE MOUNT CHIP 3220 180V	10000
8S17SM500 Maida Development Company	MOV SURFACE MOUNT CHIP 3220 50VA	10000
8S17SM400 Maida Development Company	MOV SURFACE MOUNT CHIP 3220 40VA	10000
8S17SM500T6 Maida Development Company	MOV SURFACE MOUNT CHIP 3220 50VA	10000
8S17SM100T6 Maida Development Company	MOV SURFACE MOUNT CHIP 3220 10VA	10000
D73ZOV400RA03 Maida Development Company	STANDARD MOV 40VAC	260
8S17SM200T6 Maida Development Company	MOV SURFACE MOUNT CHIP 3220 20VA	10000
8S17SM271 Maida Development Company	MOV SURFACE MOUNT CHIP 3220 270V	9975
8S17SM151 Maida Development Company	MOV SURFACE MOUNT CHIP 3220 150V	9950
SM10ZOV151RA04 Maida Development Company	MOV SURFACE MOUNT 10MM DISC	78
8S17SM950T6 Maida Development Company	MOV SURFACE MOUNT CHIP 3220 95VA	10000
8S17SM170T6 Maida Development Company	MOV SURFACE MOUNT CHIP 3220 17VA	10000
8S17SM600 Maida Development Company	MOV SURFACE MOUNT CHIP 3220 60VA	10000

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