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Littelfuse Varistors Circuit Protection Products Catalog

Littelfuse Varistors Circuit Protection Products Catalog
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Littelfuse Varistors Circuit Protection Products Catalog - 1

Expertise Applied | Answers Delivered Circuit Protection Products

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Littelfuse Varistors Circuit Protection Products Catalog - 2

Littelfuse Circuit Protection Solutions Portfolio Consumer Electronics Telecom White Goods Medical Equipment TVSS and Power Supplies Lighting General Ele DESIGN SUPPORT Live Application Design and Technical Support—Tap into our expertise. Littelfuse engineers are available around the world to help you address design challenges and develop unique, customized solutions for your products. Product Sampling Programs—Most of our products are available as samples for testing and verication within your circuit design. Visit Littelfuse.com or contact a Littelfuse product representative for...

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Littelfuse Varistors Circuit Protection Products Catalog - 3

SWITCHING TECHNOLOGIES Switching Thyristors— Solid-state switches used to control the ow of electrical current in applications, capable of withstanding rated blocking/ off-state voltage until triggered to on-state. In addition to our broad portfolio of circuit protection technologies, we offer an array of fuse holders including circuit board, panel or in-line wire mounted devices to support a wide range of application requirements. OVERCURRENT PROTECTION TECHNOLOGIES (7-8) 7. Positive Temperature Coefcient Devices (PTCs)— Provide resettable overcurrent protection for a wide range of...

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Littelfuse Varistors Circuit Protection Products Catalog - 4

Overvoltage Protection with Littelfuse Varistors Littelfuse offers Varistor protective devices with peak current ratings from 20A-70,000A, peak energy ratings from 0.01J-10,000J, and mounting options to serve a wide range of applications. The Littelfuse MLV (Multilayer Varistor) family consists of compact surface mount devices with enhanced performance and ltering characteristics for circuit board-level applications. They protect against electrostatic discharge, EFT and surge, offer low capacitance for high data rates and high capacitance for EMI ltering, and are widely used in computers,...

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Littelfuse Varistors Circuit Protection Products Catalog - 5

Varistor Products Varistor Product Selection Guide and Worksheet Introduction to Varistors and Overvoltage Suppression Varistor Products Overview: 4-7 Varistor Technology Overview Varistor Connection Examples Varistor Terms and Definitions Agency Standards MHS Series Multilayer High-Speed Surface Mount ESD Voltage Suppressors MLE Series Multilayer Surface Mount ESD Suppressor/Filter 0201 MLA Series (0201 size) Multilayer Surface Mount Transient Voltage Suppressors MLA Series Multilayer Surface Mount Transient Voltage Suppressors MLA Automotive Series Multilayer Surface Mount Transient...

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Littelfuse Varistors Circuit Protection Products Catalog - 6

Varistor Products Product Selection Guide Operating Operating Operating Technology Lines Mount/Form Peak Current Peak Energy Temperature AC Voltage DC Voltage Range (J) Type Protected Factor Range2 (A) Range Range Range Agency Approvals Disc Size UR CSA VDE CECC QPL RoHS Lead Free Halogen Free Data Sheet Page Surface Mount MLVs and MOVs: MHS MultiLayer Zinc Oxide (MLV) Surface Mount Radial Leaded MOVs: ™ Zinc Oxide Radial Leaded Industrial High Energy Terminal MOVs: BA/BB Zinc Oxide Industrial Packaged Radial Leads Screw / Clip Terminals Bare Disc Axial Leaded Inline Radial Leads Specialty...

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Littelfuse Varistors Circuit Protection Products Catalog - 7

Varistor Products Product Selection Worksheet Step 1. Determine the circuit’s operating parameters. (complete as much of the following information as possible). 1-a. Source and path of the transient ________ Source ________ Path 1-b. Normal operating voltage of protected device 1-c. Tolerance of normal operating voltage (1-b) 1-d. Max. allowable voltage of protected device 1-e. Maximum expected surge current and number of hits (Specify 8x20µs waveform equivalent of surge current) 1-f. Maximum energy applied to device in surge event 1-g. Maximum power applied to device in surge event 1-h....

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Littelfuse Varistors Circuit Protection Products Catalog - 8

Varistor Products Introduction To assure reliable operation, transient voltage suppression should be considered at early stages of the design process. This can be a complex task as electronic components are increasingly sensitive to stray electrical transients. The designer must define the types of transient threats and determine what applications are needed while meeting the product agency norms and standards. Varistors are increasingly used as the front-line solution for transient surge protection. Littelfuse provides expertise to the designer and offers the broadest range of circuit...

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Littelfuse Varistors Circuit Protection Products Catalog - 9

Varistor Products Introduction to Overvoltage Suppression Transient Threats – What Are Transients? Repeatable transients are frequently caused by the operation of motors, generators, or the switching of reactive circuit components. Random transients, on the other hand, are often caused by Lightning (Figure 1) and Electrostatic Discharge (ESD) (Figure 2). Lightning and ESD generally occur unpredictably, and may require elaborate monitoring to be accurately measured, especially if induced at the circuit board level. Numerous electronics standards groups have analyzed transient voltage...

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Littelfuse Varistors Circuit Protection Products Catalog - 10

Varistor Products Transient Voltage Scenarios ESD (Electrostatic Discharge) Electrostatic discharge is characterized by very fast rise times and very high peak voltages and currents. This energy is the result of an imbalance of positive and negative charges between objects. Below are some examples of the voltages which can be generated, depending on the relative humidity (RH): • Walking across a carpet: 35kV @ RH = 20%; 1.5kV @ RH = 65% • Walking across a vinyl floor: 12kV @ RH = 20%; 250V @ RH = 65% • Worker at a bench: kV @ RH = 20%; 100V @ RH = 65% 6 • Vinyl envelopes: 7kV @ RH = 20%;...

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Littelfuse Varistors Circuit Protection Products Catalog - 11

Varistor Products Figure 5 shows the effect of a cloud-to-ground strike: the transient–generating effect is far greater. Technological Solutions for Transient Threats Because of the various types of transients and applications, it is important to correctly match the suppression solution to the different applications. Littelfuse offers the broadest range of circuit protection technologies to ensure that you get the proper solution for your application. Please consult our online library of Application Notes and Design Notes for further information on common design issues encountered at...

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