Open Air Sense Resistors Metal Alloy Strip OARS-3 Series OARS-3 * Higher than standard 1 Watt rating for 2512 pad design Airjumper Sense Resistors *Open Zero ohm available *Metal Economical low resistance SMT Alloy Strip * Resistance values 2m to 15m * 1% or 5% tolerance (0.002 5% only) s Higher than standard 1 Watt rating for 2512 pad design * Open air design provides cooler operation s Zero ohm jumper available s s s s Economical low resistance SMT Resistance values 2m to 15m 1% or 5% tolerance (0.002 5% only) Open air design provides cooler operation Electrical Data 1 IRC Type Power Rating (watts) Available Resistance OARS-3 3W @ 70C .002, .003, .004, .005, .010, .015 (ohms) 1 Non-Standard un-listed resistance values can be made available, subject to engineering charges and/or minimum order requirements. Features: Applications: s 3UPErior thermal expansion cycling s #URRENT SENSING s &LAMEPROOF s &eedback s )NDUCTANCE LESS THAN NANOHENries s ,ow inductance s ,EAD flexible for thermal expansion s 3URGE AND PULSE s AC 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 Type OARS-3 OARS-3 0.002 OARS-3 0.003 L H T D W 0.440 0.015 0.120 0.030 0.093 0.010 0.190 0.030 0.125 0.015 (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 (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 (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 specification without notice or liability. General Note All information is subject to IRC's own data and is considered accurate at time of going to print. TT electronics reserves the right to make changes in product specification without notice or liability. Wire and Film Technologies Division s 3OUTH 3TAPLES 3TREET s #Orpus Christi TeXAS 53! All information is subject to TT own www.irctt.com data and is considered accurate at time of going to print. Telephone: s Facsimile: electronics' s Website: A Subsidiary of TT electronics plc July 2011 Issue Page 1 of 4 www.bitechnologies.com www.irctt.com www.welwyn-tt.com (c) TT electronics plc 09. 11 OARS-3 Open Air Sense Resistors Metal Alloy Strip Open Air Sense Resistors Metal Alloy Strip OARS-3 Series Environmental Data Test Spec: AEC Q200 2m - 3m 4m - 15m TCR +125 to -55C 240ppm 40ppm Thermal Shock <0.75% <0.75% High Temperature Exposure 125C <1.75% <0.5% Temperature Cycling: -40 to +125C <1.0% <1.0% Operational Life <2.0% <1.0% Baised Humidity <0.75% <0.5% Mechanical Shock <1.5% <1.0% Vibration <1.0% <1.0% <1.0 <2.5% Moisture Resistance Terminal Strength Meets JIS-C-6429 Solvent Resistance Meets MIL-STD-202 Method 215 Solderability Meets J-STD-002 Method B Power Derating Curve 3.5 Note: The power derating curve is a guidance based on a conservative design model. The OARS is a solid metal alloy construction that can withstand signicantly greater operating temperatures than conservative design models permit. The resistive alloys can withstand temperatures in exess of 350C. Therefore, the system thermal design is a more signicant design parameter due to the heat limitations of solder joints and/or circuit board substrate materials. Refer to additional information below. Power Rating (watts) 3.0 2.5 2.0 1.0 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 5 m running at 4 Watts, which exceeds the 1 Watt conservative model. Notice the hotpsot is nearly 230C, but the solder joint is approximately 110C (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. OARS R005 Thermal Image @ 4 Watts Ambient conditions, No forced air. 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 more details or for other thermal image test data for specic resistance values and power levels. Wire and Film Technologies Division s 3OUTH 3TAPLES 3TREET s #OrPUS #Hristi TeXAS 53! Telephone: s Facsimile: s Website: www.irctt.com July 2011 Issue Page 2 of 4 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 (c) TT electronics plc 09. 11 OARS-3 Open Air Sense Resistors Metal Alloy Strip Open Air Sense Resistors Metal Alloy Strip OARS-3 Series Pulse/Surge Chart Note: 70 The high pulse/surge capability of the OARS parts is attributed to the solid metal alloy construction. In many applications the cross-section of the OARS is greater than the cross-section of the board traces connecting the parts to the circuit board. Joules (watts-second) 60 50 40 Cross-Sectional area ranges from approximately 780 mils to 3600 mils. 30 20 10 0 0 5 10 15 20 Resistance (milli ohms) Tape Specifications G E D C B F A Dimensions (Inches and (mm)) IRC Type OARS-3 A B C D E F G 0.17 0.003 0.461 0.003 0.945 0.010 0.453 0.004 0.069 0.004 0.315 0.004 0.157 0.004 (4.32 0.08) (11.7 0.08) (24.0 0.30) (11.5 0.10) (1.75 0.10) (8.0 0.10) (4.0 0.1) Ordering Data Sample Part No. OARS3 R005 J LF IRC Type OARS3 Power Rating in Watts Resistance Range (ohms) Tolerance F = 1%, G = 2%, J = 5% RoHS Indicator LF indicates RoHS compliance Wire and Film Technologies Division s 3OUTH 3TAPLES 3TREET s #OrPUS #Hristi TeXAS 53! Telephone: s Facsimile: s Website: www.irctt.com July 2011 Issue Page 3 of 4 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 (c) TT electronics plc 09. 11 OARS-3 Open Air Sense Resistors Metal Alloy Strip Open Air Sense Resistors OARS-3 Series Metal Alloy Strip IRC Solder Reflow Recommendations Sn-Pb Eutectic and Pb-Free Reflow Profiles tP TP Ramp-up Critical Zone TL to TP TL tL Te m p e r a t u r e Tsmax Tsmin ts Preheat 25 Ramp-down t 25C to Peak Time * Based on Industry Standards and IPC recommendations Profile Feature Sn-Pb Eutectic Assembly Pb-Free Assembly 3C / second max. 3C / second max. Preheat - Temperature Min (Tsmin) - Temperature Max (Tsmax) - Time (Tsmin to Tsmax) (ts) 100C 150C 60 -120 seconds 150C 200C 60 -180 seconds Time maintained above - Temperature (TL) - Time (tL) 183C 60 - 150 seconds 217C 60 - 150 seconds Average Ramp-up rate (Tsmax to Tp) Peak Temperature (TP) Time within 5C of actual Peak Temperature (tp)2 Ramp-down Rate Time 25C to Peak Temperature See Table 1 See Table 2 10 - 30 seconds 20 - 40 seconds 6C / second max. 6C / second max. 6 minutes max. 8 minutes max. Tabel 1: SnPb Eutectic Process Package Peak Reflow Temperatures Package Thickness Volume mm3 < 350 Volume mm3 350 < 2.5 mm 240 +0/-5C 225 +0/-5C 2.5 mm 225 +0/-5C 225 +0/-5C Tabel 2: Pb-free Process Package Peak Reflow Temperatures Package Thickness Volume mm3 < 350 Volume mm3 350 - 2000 Volume mm3 > 2000 260C * < 1.6 mm 260C * 260C * 1.6 mm - 2.5 mm 260C * 250C * 245C * 2.5 mm 250C * 245C * 245C * Note 1: All temperatures refer to topside of the package, measured on the package body surface. Note 2: Time within 5 C of actual peak temperature (tp) specied for the reow proles is a "supplier" minimum and a "user" maximum. Note 1: Package volume excludes external terminals (balls, bumps, lands, leads) and/or non-integral heat sinks. Note 2: The maximum component temperature reached during reow depends on package thickness and volume. The use of convection reow processess reduces the thermal gradients between packages. However, thermal gradients due to differences in thermal mass of SMD packages may still exist. Note 3: Components intended for use in "leadfree" assembly process shall be evaluated using the "lead-free" peak temperature and proles dened in Table 1, 2 and reow prole whether or not lead-free. * Tolerance: The device manufacturer/supplier shall assure process compatibility up to and including the stated classication temperature at the rated MSL level. Wire and Film Technologies Division s 3OUTH 3TAPLES 3TREET s #OrPUS #Hristi TeXAS 53! Telephone: s Facsimile: s Website: www.irctt.com July 2011 Issue Page 4 of 4 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 (c) TT electronics plc 09. 11