LTO50

LTO 50 Vishay Sfernice Power Resistor Thick Film Technology features • 50 Watt at 25 °C Case Temperature Heatsink Mounted • Direct mounting ceramic on heatsink • Broad Resistance Range: R010 to 550K • Non Inductive • TO-220 package: Compact and easy to mount LTO series are the extension of RTO types. We used the direct ceramic mounting design (no metal tab) of our RCH power resistors applied to semiconductor packages. • RoHS compliant • Isolated case RoHS COMPLIANT dimensions in millimeters 10.4 3.2 3.2 Ø3.2 16.2 1.3 0.8 3.5 12.7 0.6 5.08 1.8 • Tolerance unless otherwise specified: ± 0.3 mm mechanical specifications Mechanical Protection Resistive Element Substrate Connections Weight Mounting Torque Molded Thick Film Alumina Tinned Copper 2 g max. 1 N-m electrical specifications Resistance Range Tolerances (Standard) Dissipation and Associated Power Rating and Thermal Resistance of the component Temperature Coefficient 0.010 Ω to 550 kΩ ± 1 % to ± 10 % Onto a heatsink 50 W at + 25 °C (case temperature) RTH (j-c): 2.5 °C/W free air: 2.5 W at + 25 °C See Performance table ± 150 ppm/°C 250 V 1500 VRMS - 1 minute - 10 mA max. ≥ 104 MΩ ≤ 0.1 μH 1.25 kΩ dimensions Standard Package TO-220 Isolated case Dielectric Strength MIL STD 202 Insulation Resistance Inductance Critical Resistance Standard Limiting Element Voltage environmental specifications Temperature Range Climatic Category - 55 °C to + 150 °C 55/155/56 www.vishay.com 14 For technical questions, contact sfer@vishay.com Document Number: 50050 Revision 26-Mar-07 LTO 50 Power Resistor Thick Film Technology performance TESTS Momentary Overload CONDITIONS EN60115-1 1.5 Pr/5 s Us < 1.5 UL EN60115-1 IEC 60068-2-14 Tests Na 5 cycles - 55 °C to + 155 °C EN60115-1 1000 h Pr at + 25 °C MIL STD 202 Method 103 B Cond. D MIL STD 202 Method 204 Cond. D MIL STD 202 Method 211 Cond. A1 100G, MIL STD 202 Method 213 Cond. I TYPICAL DRIFTS ± (0.5 % + 0.005 Ω) Vishay Sfernice Rapid Temperature Change ± (0.5 % + 0.005 Ω) Load Life Humidity (Steady State) Vibration Terminal Strength Shock ± (1 % + 0.005 Ω) ± (0.5 % + 0.005 Ω) ± (0.2 % + 0.005 Ω) ± (0.2 % + 0.005 Ω) ± (0.5 % + 0.005 Ω) special features Resistance Values Tolerances Typical Temperature Coefficient (- 55 °C/+ 150 °C) ± 900 ppm/°C ≥ 0.010 ≥ 0.015 ± 1 % at ± 10 % ± 700 ppm/°C ± 250 ppm/°C ± 150 ppm/°C ≥ 0.1 ≥ 0.5 choice of the heatsinK The user must choose according to the working conditions of the component (power, room temperature). Maximum working temperature must not exceed 150 °C. The dissipated power is simply calculated by the following ratio: ∆T [RTH (j-c) + RTH (c-a)] (1) P= P: ∆T: expressed in W difference between maximum working temperature and room temperature. RTH: (j-c): thermal resistance value measured between resistive layer and outer side of the resistor. It is the thermal resistance of the component. RTH: (c-a): thermal resistance value measured between outer side of the resistor and room temperature. It is the thermal resistance of the heatsink itself (type, shape), the quality of the fastening device, and the thermal resistance of the thermal compound. Example: RTH: (c-a) for LTO50 power rating 10 W at ambient temperature + 25 °C. Thermal resistance RTH (j-c): 2.5 °C/W Considering equation (1) we have: ∆T = 150 °C - 25 °C = 125 °C 125 ∆T RTH (j-c) + RTH (c-a) = = = 12.5 °C/W 10 P RTH (c-a) = 12.5 °C/W - 2.5 °C/W = 10 °C/W with a thermal grease RTH (c - h) = 1 °C/W, we need a heat sink with RTH (h - a) = 9 °C/W. Document Number: 50050 Revision 26-Mar-07 For technical questions, contact sfer@vishay.com www.vishay.com 15 LTO 50 Vishay Sfernice overloads Power Resistor Thick Film Technology In any case the applied voltage must be lower than the maximum overload voltage of 375V. The values indicated on the graph below are applicable to resistors in air or mounted onto a heatsink. enerGY curve ENERGY IN JOULES 10 1 0.1 0.01 10 -6 10 -5 10-4 10 -3 10 -2 OVERLOAD DURATION IN SECONDS power ratinG chart The temperature of the heatsink should be maintained within the limits specified. To improve the thermal conductivity, surfaces in contact should be coated with a silicone grease and the torque applied on the screw for tightening should be around 1 Nm. 100 % RATED POWER 75 50 25 0 0 20 40 60 80 100 120 140 150 marKinG HEATSINk TEMPERATURE IN DEGREES CELSIUS Model, Style, Resistance Value (in Ω), Tolerance (in %), Manufacturing Date, VISHAY trademark pacKaGinG Tube of 50 units orderinG information LTO MODEL 50 STYLE F CONNECTIONS 100 kΩ RESISTANCE VALUE ±1% TOLERANCE ±1% ±2% ±5% ± 10 % xxx CUSTOM DESIGN Optional on request: special TCR, shape etc. TU50 PACKAGING e3 LEAD (Pb)-FREE sap part numberinG Guidelines L T MODEL O 0 5 STYLE 0 F CONNECTIONS 1 0 0 RESISTANCE VALUE 0 2 F TOL T E 3 PACK LEAD (Pb)-FREE SAP Part Number LTO050F10002FTE3 www.vishay.com 16 For technical questions, contact sfer@vishay.com Document Number: 50050 Revision 26-Mar-07 Legal Disclaimer Notice Vishay Notice Specifications of the products displayed herein are subject to change without notice. Vishay Intertechnology, Inc., or anyone on its behalf, assumes no responsibility or liability for any errors or inaccuracies. Information contained herein is intended to provide a product description only. No license, express or implied, by estoppel or otherwise, to any intellectual property rights is granted by this document. Except as provided in Vishay's terms and conditions of sale for such products, Vishay assumes no liability whatsoever, and disclaims any express or implied warranty, relating to sale and/or use of Vishay products including liability or warranties relating to fitness for a particular purpose, merchantability, or infringement of any patent, copyright, or other intellectual property right. The products shown herein are not designed for use in medical, life-saving, or life-sustaining applications. Customers using or selling these products for use in such applications do so at their own risk and agree to fully indemnify Vishay for any damages resulting from such improper use or sale. Document Number: 91000 Revision: 08-Apr-05 www.vishay.com 1