RTO 20 www.vishay.com Vishay Sfernice 20 W Power Resistor, Thick Film Technology, TO-220 FEATURES 20 W at 25 C heatsink mounted High power dissipation to size ratio Wide resistance range from 0.01 to 550 k Negligible inductance Easy mounting TO-220 package: compact and easy to mount Material categorization: for definitions of compliance please see www.vishay.com/doc 99912 Two versions of this thick film resistor are available: A radial leaded version for PCB mounting The well known TO-220 package is compact and easy to A flat lead version for surface mounting mount. DIMENSIONS in millimeters RTO 20F - LEADED RTO 20C - FOR SURFACE MOUNTING 4.5 4.5 10.1 10.1 1.3 3.6 3.6 1.3 15 12.5 15 12.5 8.8 8.8 2 3 13.7 1.6 0.3 5.08 2.5 0.8 Only for RTO 20 version C = during surface mount soldering temperature profile 5.08 must not cause the metal tab of this device to exceed 220 C. Note Tolerances unless stated: 0.4 mm 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 20 TO-220 0.010 to 550K 20 500 1, 2, 5, 10 150 12.5K Note (1) E24 series MECHANICAL SPECIFICATIONS TECHNICAL SPECIFICATIONS Mechanical Protection Insulated case Dissipation and Onto a heatsink Associated Resistive Element Thick film 20 W at + 25 C Alumina onto base of nickel coated Substrate Thermal Resistance R : 6.5 C/W TH (j - c) copper and Nominal Power Free air: Connections Tinned copper 2 W at +25 C Weight 2.2 g max. Dielectric Strength 2000 V - 1 min - 10 mA max. RMS MIL STD 202 (between terminals and heatsink) ENVIRONMENTAL SPECIFICATIONS 6 Insulation Resistance 10 M Temperature Range -55 C to 155 C Inductance 0.1 H Climatic Category 55/155/56 Sealing Sealed container, solder immersion DIMENSIONS IEC 60695-11-5 Standard Package TO-220 insulated case Flammability 2 applications 30 s separated by 60 s Note Not compatible with RoHS reflow profile. Revision: 18-Sep-15 Document Number: 50005 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 20 www.vishay.com Vishay Sfernice PERFORMANCE TESTS CONDITIONS REQUIREMENTS EN 60115-1 2 Pr 5 s for R < 2 Momentary Overload (0.25 % + 0.005 ) 1.6 Pr 5 s for R 2 U < 1.5 U S L EN 60115-1/60068-2-14 Rapid Temperature Change 5 cycles (0.5 % + 0.005 ) -55 C to +155 C EN 60115-1 Load Life (1 % + 0.005 ) 1000 h Pr at +25 C EN 60115-1 Humidity (Steady State) (0.5 % + 0.005 ) 56 days RH 95 % NF EN 140 000 High Temperature Exposure (0.5 % + 0.005 ) 1000 h - 40 % Pr at +100 C Vibration MIL STD 202, Method 204 C Test D (0.2 % + 0.005 ) Terminal Strength MIL STD 202, Method 211 Test A1 (0.2 % + 0.005 ) IEC 60115-1 Shock IEC 60068-2-27 (0.5 % + 0.005 ) Saw tooth: 100 g/6 ms RESISTANCE VALUE IN RELATION TO TOLERANCE AND TCR Resistance Values 0.01 0.015 0.1 0.5 Tolerances 1 % at 10 % Typical Temperature Coefficient Range 900 ppm/C 700 ppm/C 250 ppm/C 150 ppm/C (-55 C to +155 C) Note For very low ohmic values, TCR for information. CHOICE OF THE HEATSINK The user must choose the board 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 the thermal TH (j - c) resistance of the component: Special Features table. R : Thermal resistance value measured between outer side of the resistor and upper side of the heatsink. This is the TH (c - h) 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 20 power rating 10 W at ambient temperature +25 C TH (c - a) Thermal resistance R : 6.5 C/W TH (j - c) (1) Considering equation we have: T = 155 C - 25 C = 130 C T 130 R + R + R = ------- = -------- = 13 C/W TH (j - c) TH (c - h) TH (h - a) P 10 R + R = 13 C/W - 6.5 C/W = 6.5 C/W TH (c - h) TH (h - a) Revision: 18-Sep-15 Document Number: 50005 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