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Littelfuse Resettable PTC's Catalog

Littelfuse Resettable PTC's Catalog
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Littelfuse* Expertise Applied | Answers Delivered Gas Discharge Tube (GDT) Products

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Littelfuse* Expertise Applied | Answers Delivered GDT Characteristics, Terms and Consideration Factors Legal Disclaimers Very High Surge GDTs 10A* 20000A* © 2017 Littelfuse, Inc. Specifications, descriptions and illust rative material in this literature are rs accurate as k7own at the time of publication, but are subject to change without notice. Visit www.littelfuse.com for more information. (1) Please refer to product data in our datasheets for detailed information by part number. * Total current through center (ground) terminal

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GDT Characteristics, Terms and Consideration Factors A Comparison of Surge Arrester Technologies Surge Arresters Littelfuse gas discharge tube (GDT) surge arrester devices protect personnel and electrical equipment from damaging high voltage transients induced by lightning, inductive switching, or electrostatic discharge. Depending upon the application, Littelfuse offers a variety of two and three electrode GDTs for protecting telecommunication, test, computer, power supply, medical, and cable television equipment. Along with protecting circuits, GDTs can also be used as switches to create...

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GDT Characteristics, Terms and Consideration Factors (continued) Comgap Gas Discharge Tube Voltage vs. Current Characteristics Littelfuse’s GDT, a hermetically sealed gas filled ceramic tube with metal electrodes, is recognized for: • Stable electrical parameters • High insulation resistance • Low capacitance • High current capability • Low leakage current • Low arc voltages For a gas tube to begin conduction, an electron within the sealed device must gain sufficient energy to initiate the ionization of the gas. Complete ionization of the gas takes place through electron collision. The...

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GDT Characteristics, Terms and Consideration Factors (continued) voltage. The zener is a good protector for circuits operating at low voltages. Caution is advised when designing the device into RF circuits due to the diode’s high capacitance. Also available are silcon avalanche suppressers which are referred to as transient voltage suppressers (TVS) diodes. These diodes consist of fairly large junction zeners which Breakdown have been designed specifically for surge protection. The Voltage TVS diodes are rated for higher current surges than zener Zener diodes and they Voltage these currents...

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GDT Characteristics, Terms and Consideration Factors (continued) through the device increases, the voltage which the MOV clamps at is greatly increased. Upturn Region Leakage Region MOV Voltage vs. Current Characteristics In contrast, most devices in Littelfuse’s High Energy Devices product line are glass-to-metal units. This allows greater flexibility in configuration and is ideal for the production of standard and custom parts in more limited quantities. The electrodes of High Energy Devices are usually made of refractory metals such as tungsten or molybdenum to meet more extreme life and...

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M Llttelfuse Expertise Applied | Answers Delivered THEORY The basic operation of gas tube surge arrestors such as Littelfuse's GDTs is best understood by referring to the schematic form of the voltage-current (V-i) relationship of a generic gas discharge device such as the one depicted in Figure 1. A For voltages below the breakdown voltage, the gas provides a good insulator. Very low leakage currents (10-12A) occasionally encountered result from ionization by cosmic rays, high energy photons, etc; and is, therefore, subject to statistical fluctuations. A1 The current is higher due to...

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Gas Discharge Tubes Legal Disclaimers Liability Littelfuse, Inc. its affiliates, agents, and employees, and all persons acting on its or their behalf (collectively, “Littelfuse”), disclaim any and all liability for any errors, inaccuracies or incompleteness contained here or in any other disclosure relating to any product. Littelfuse disclaims any and all liability arising out of the use or application of any product described herein or of any information provided herein to the maximum extent permitted by law. The product specifications do not expand or otherwise modify Littelfuse terms and...

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Littelfuse Resettable PTC's Catalog - 10

Two Electrode GDT Graphical Symbol The Littelfuse CG4 Gas Discharge Tubes (GDT) series provides high levels of protection against fast rising transients caused by lightning disturbances. Offered in a miniature surface mount package, it has a surge rating of 3kA 8/20ps. Littelfuse CG4 mini GDTs are high voltage (8003000V) components designed for surge protection and high isolation applications. It is also suitable for applications for which bias voltage or signal levels of several hundred volts are normally present. CG4 mini GDTs can be used in conjunction with Littelfuse MOVs (Metal Oxide...

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Littelfuse Resettable PTC's Catalog - 11

Littelfuse* Expertise Applied | Answers Delivered Electrical Characteristics Life Ratings Reflow Condition © 2017 Littelfuse, Inc. Specifications are subject to change without notice. Revised: 12/12/17

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Littelfuse Resettable PTC's Catalog - 12

Gas Discharge Tubes. CG4 Series Expertise Applied | Answers Delivered Device Dimensions Product Marking Dimensions in millimeters PROFILE VIEW Littelfuse Logo Production Year Code Part Numbering System and Ordering Information ■ 1.3 | CG4 x.x SM Series -CG4 Recommended Soldering Pad Layout Breakdown Voltage - 0.8 = 800V 1.0 = 1000V 3.0 = 3000V (Voltage code examples for x.x) Lead Option Code SM (Surface Mount, Taping and Reel Specifications P2 Packaging Quantity: 1000 pcs per reel (13")1 reels per inner box 10 inners box per carton 10,000 pcs per full carton 18 Typ. Disclaimer Notice -...

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Littelfuse Resettable PTC's Catalog - 13

Gas Discharge Tubes AC and CG3 Series AC and CG3 Series Littelfuse* Expertise Applied | Answers Delivered Littelfuse AC series two-electrode line protectors provide a high degree of surge protection in AC line applications. The two models, AC120 and AC240 are designed for use with 120VAC and 240VAC lines respectively. They are able to extinguish AC follow-on currents of at least 200A. Littelfuse CG3 two electrode high voltage (1.0 - 75 KV) devices are designed for surge protection and high isolation applications, and for applications for which bias voltages or signal levels of several...

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