RTO 50 www.vishay.com Vishay Sfernice 50 W Power Resistor, Thick Film Technology, TO-220 FEATURES 50 W at 25 C heatsink mounted Adjusted by sand trimming Leaded or surface mount versions High power to size ratio Non inductive element Material categorization: for definitions of compliance please see www.vishay.com/doc 99912 Because of the knowledge and experience in Thick Film technology, Vishay Sfernice has been able to develop a high power resistor in a TO-220 package called RTO 50. The special design of this component allows the dissipation of 50 W when mounted on a heatsink. The ohmic value is adjusted by sand trimming. This process does not generate hot spots as in laser trimming, which could lead to microcracks on each side of the curve. This process improves the reliability and the stability of the resistor and at the same time gives a good overload capability. DIMENSIONS in millimeters RTO 50F - LEADED RTO 50C - FOR SURFACE MOUNTING 4.5 4.5 10.1 10.1 1.3 3.6 3.6 1.3 15 15 12.5 12.5 8.8 8.8 2 3 13.7 0.3 1.6 5.08 2.5 0.8 Only for RTO 50 version C = during surface mount soldering, the soldering temperature profile must not cause the metal tab of this 5.08 device to exceed 220 C. STANDARD ELECTRICAL SPECIFICATIONS RESISTANCE RATED POWER LIMITING ELEMENT TEMPERATURE CRITICAL TOLERANCE MODEL SIZE RANGE P VOLTAGE U COEFFICIENT RESISTANCE 25 C L % W V ppm/C (1) RTO 50 TO-220 0.010 to 550K 50 500 1, 2, 5, 10 150 5K Note (1) E24 series MECHANICAL SPECIFICATIONS TECHNICAL SPECIFICATIONS Mechanical Protection Molded Dissipation and Associated Onto a heatsink Resistive Element Thick film 50 W at +25 C Thermal Resistance Connections Tinned copper alloy R : 2.6 C/W TH (j - c) and Nominal Power Weight 2.2 g max. Free air: 2.25 W at +25 C Dielectric Strength 2000 V - 1 min RMS ENVIRONMENTAL SPECIFICATIONS MIL STD 202 (301) 10 mA max. 6 Temperature Range -55 C to 155 C Insulation Resistance 10 M Climatic Category 55/155/156 Inductance 0.1 H Sealing Sealed container, solder immersion DIMENSIONS IEC 60695-11-5, Flammability 2 applications 30 s separated by 60 s Standard Package TO-220 insulated case Note Not compatible with RoHS reflow profile. Revision: 18-Sep-15 Document Number: 50035 1 For technical questions, contact: sferfixedresistors vishay.com THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc 91000RTO 50 www.vishay.com Vishay Sfernice PERFORMANCE TESTS CONDITIONS REQUIREMENTS EN 60115-1 2 Pr 5 s for R < 2 Momentary Overload (0.25 % + 0.05 ) 1.6 Pr 5 s for R 2 U < 1.5 U S L EN 60115-1 Rapid Temperature Change 60 068-2-14 (0.5 % + 0.05 ) 5 cycles -55 C to +155 C EN 60115-1 Load Life (1 % + 0.05 ) Pr at +25 C, 1000 h CEI 115 1 EN 60115-1 Humidity (Steady State) (0.5 % + 0.05 ) 56 days RH 95 % MIL STD 202 Vibration (0.2 % + 0.05 ) method 204 C test D MIL STD 202 Terminal Strength (0.2 % + 0.05 ) method 211 test A1 RESISTANCE VALUE IN RELATION TO TOLERANCE AND TCR Resistance Values 0.01 0.015 0.1 0.5 Tolerances 1 % at 10 % Temperature Coefficient Standard 900 ppm/C 700 ppm/C 250 ppm/C 150 ppm/C (-55 C to +155 C) 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 155 C. The dissipated power is simply calculated by the following ratio: 1 T P = ------------------------------------------------------------------------------------------- R ++R R TH (j - c) TH (c - h) TH (h - a) P: Expressed in W T: Difference between maximum working temperature and room temperature R : Thermal resistance value measured between resistive layer and outer side of the resistor. It is TH (j - c) the thermal resistance of the component: (Special Features Table) R : Thermal resistance value measured between outer side of the resistor and upper side of the TH (c - h) heatsink. This is the thermal resistance of the interface (grease, thermal pad), and the quality of the fastening device R : Thermal resistance of the heatsink TH (h - a) Example: R : For RTO 50 power rating 13 W at ambient temperature +30 C TH (c - a) Thermal resistance R : 2.6 C/W TH (j - c) (1) Considering equation we have: T 155 C - 30 C = 125 C T 125 ------- R + R + R = = -------- = 9.6 C/W TH (j - c) TH (c - h) TH (h - a) P 13 R + R 9 .6 C/W - 2.6 C/W 7 C/W TH (c - a) TH (h - a) Revision: 18-Sep-15 Document Number: 50035 2 For technical questions, contact: sferfixedresistors vishay.com THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc 91000