Open Air Sense Resistors Metal Alloy Strip OARS Series OARS Greater than 1 Watt rating for 2512 pad design Open Air Sense Resistors Zero ohm jumper available, OARSZ Economical low value SMT Metal Alloy Strip Resistance values 2m to 50m 1% or 5% tolerance s Greater than 1 W att rating for 2512 pad design Open air design provides cooler operation s Zero ohm jumper available, OARSZ Economical ls o w value SMT s Resistance v alues 2m to 50m s 1% or 5% toler ance s Open air design pro vides cooler operation Electrical Data Power Rating Available Resistance IRC Type (watts) (ohms) .002, .003, .004, .005, .010, .015 OARS-1 1W 70C .020, .022, .025, .030, .040, .050 1 Non-Standard un-listed resistance values can be made available, subject to engineering charges and/or minimum order requirements. Features: Applications: s 3UPEr ior thermal expansion cycling s URRENT SENSING s &LAMEPROOF &s eedback s )NDUCTANCE LESS THAN NANOHENr ies s ,o w inductance s ,EAD exible for thermal expansion s 3URGE AND PULSE s A C applications (please contact the factory) Physical Data Recommended Landing Pad Size , 0.369 W 0.121 0.127 0.121 0.126 D T H Dimensions (Inches and (mm)) IRC L H T D W Type 0.440 0.015 0.120 0.030 0.093 0.010 0.190 0.030 0.125 0.015 OARS-1 (11.18 0.381) (3.05 0.762) (2.36 0.254) (4.83 0.762) (3.175 0.381) 0.455 .015 0.150 0.030 0.093 0.010 0.185 0.030 0.140 0.015 OARS-1 0.002 (11.56 .381 ) (3.51 0.762) (2.36 0.254) (4.70 0.762) (3.56 0.381) 0.440 .015 0.138 0.030 0.093 0.010 0.180 0.030 0.125 0.015 OARS-1 0.003 (11.18 .381 ) (3.51 0.762) (2.36 0.254) (4.83 0.762) (3.175 0.381) General Note IRC reserves the right to make changes in product speci cation without notice or liability. All inGeneral Noteformation is subject to IRCs own data and is considered accurate at time of going to print. A Subsidiary of TT electronics reserves the right to make changes in product specification without notice or liability. TT electronics plc Wire and Film Technologies Division rs 3OUTH 3TAPLES 3TREET s O pus Christi TeXAS 53 July 2011 Issue Page 1 of 4 All information is subject to TT electronics own data and is considered accurate at time of going to print. Telephone:F s acsimile: s Website: www.irctt.com www.bitechnologies.com www.irctt.com www.welwyn-tt.com TT electronics plc 09. 11OARS Open Air Sense Resistors Metal Alloy Strip Open Air Sense Resistors OARS Series Metal Alloy Strip Environmental Data AEC Q200 Test Spec: 2m - 3m 4m - 15m > 15m TCR +125 to -55C 240ppm 40ppm 40ppm Thermal Shock < 0.75% < 0.75% < 0.75% High Temperature Exposure 125C < 1.75% < 0.5% < 1.0% Temperature Cycling: -40 to +125C < 1.0% < 1.0% < 0.75% Operational Life < 2.0% < 1.0% < 1.0% Baised Humidity < 0.75% < 0.5% < 0.5% Mechanical Shock < 1.5% < 1.0% < 1.0% Vibration < 1.0% < 1.0% < 1.0% Moisture Resistance < 1.0 < 2.5% < 2.0 Terminal Strength Meets JIS-C-6429 Solvent Resistance Meets MIL-STD-202 Method 215 Solderability Meets J-STD-002 Method B Reference Documents: MIL-STD-202 Power Derating Curve 2.5 Note: The power derating curve is a guidance based on a con- 2.0 servative design model. The OARS is a solid metal alloy construction that can withstand signi cantly greater operat- ing temperatures than conservative design models permit. 1.5 The resistive alloys can withstand temperatures in excess of 350C. Therefore, the system thermal design is a more 1.0 signi cant design parameter due to the heat limitations of solder joints and/or circuit board substrate materials. Refer to 0.5 additional information below. 0.0 25 60 95 130 165 195 225 Ambient Temperature (C) The thermal image (not a simulation) to the left is of an OARS 10 m running at 2 Watts, which exceeds the 1 Watt conser- vative model. Notice the hotpsot is nearly 200C, but the sol- der joint is approximately 65C (FR4 is rated for 130C). The unique construction of the OARS isolates the hotspot from the circuit board material preventing damage. Additionally, the thermal energy is dissipated to the air instead of being conducted into the circuit board potentially causing a nearby power component to exceed its rating. The standard test circuit board consists of a four layer FR4 material with 2 ounce outer layers and 1 ounce inner layers, which is typical of many industry designs. Contact IRC for OARS R005 Thermal Image 2 Watts more details or for other thermal image test data for speci c Ambient conditions, No forced air. resistance values and power levels. Wire and Film Technologies Division rs 3OUTH 3TAPLES 3TREET s O rPUS H isti TeXAS 53 July 2011 Issue Page 2 of 4 Telephone:F s acsimile: s Website: www.irctt.com General Note TT electronics reserves the right to make changes in product specification without notice or liability. All information is subject to TT electronics own data and is considered accurate at time of going to print. www.bitechnologies.com www.irctt.com www.welwyn-tt.com TT electronics plc 09. 11 Power Rating (watts)