Open Air Resistor Metal Element Current Sense OAR OAR OAR Series /PEN 2ESISTOR /PEN !IR !IR 2ESISTOR #URRENT 3ENSE *-ETAL TCR's to%LEMENT 20ppm/C -ETAL %LEMENT #URRENT 3ENSE * Power ratings of 1, 3, & 5W @ 85C TO PPM # from 2.5m to 100m *s TCR'S Resistance range s TCR'Ss TO PPM # OF 7 POwER rATINGS # thermal performance * rATINGS Open air design maximizes s POwER OF rANGE 7 # TO M s 2ESISTANCE FROM M *s Welded copper leads minimize effects from s 2ESISTANCE FROM MAXIMIzES M TO M /PENrANGE AIR DESIGN THErMAL PERFOrMANCE solder wicking and provide true 1% performance s /PENs AIR DESIGNCOPPER MAXIMIzES 7ELDED LEADS THErMAL MINIMIzEPERFOrMANCE EFFECTS FROM SOLDER WICKING AND PROVIDE s 7ELDEDTrUE COPPER LEADS MINIMIzE EFFECTS FROM SOLDER WICKING AND PROVIDE PERFOrMANCE TrUE PERFOrMANCE Features: s 7ELDED CONSTrUCTION Features: s &LAMEPROOF s 7ELDED CONSTrUCTION s )NDUCTANCE LESS THAN NANOHENrIES s &LAMEPROOF s 3OLDErabLE COPPER AND ,EAD &ree s )NDUCTANCE LESS THAN LEADS NANOHENrIES Applications: s #URRENT SENSING Applications: s &EEDBACk s #URRENT SENSING s -OTOR #ONTROLLERS s &EEDBACk s POwER 3UPPLIES s -OTOR #ONTROLLERS s 3OLDErabLE COPPER LEADS AND ,EAD &ree s POwER 3UPPLIES %LECTrICAL $ATA Power Rating %LECTrICAL $ATA Part @ 85C Number Power Rating (watts) Part @ 85C Number OAR-1 (watts) Resistance Range (m) Resistance Range (m) OAR-1 OAR-3 OAR-3 OAR-5 Tolerance (%) Tolerance (%) TCR (ppm/C) TCR (ppm/C) Inductance (nH) Inductance (nH) Notes: OAR-5 TOLErANCE avAILAbLE M DENOTES RESISTANCE vALUES THAT MaY HavE LONGER LEAD TIMES THAN OTHER vALUES LISTED Notes: 0LEASE CONTACT FACTOrY FOR RESISTANCE vALUES NOT LISTED TOLErANCE avAILAbLE M DENOTES RESISTANCE vALUES THAT MaY HavE LONGER LEAD TIMES THAN OTHER vALUES LISTED 0LEASE CONTACT FACTOrY FOR RESISTANCE vALUES NOT LISTED ENVIRONMENTAL $ATA Load Life (1000 hours$ATA @ 25C) ENVIRONMENTAL R/R <1% Moisture (no load for 1000 hours) Load Life (1000 hours @ 25C) R/R R/R <1% <1% Temperature (-40C to +125C for 1000 cycles) Moisture (no load forCycling 1000 hours) R/R R/R <1% <1% OperaCycling ting Tem(-40C peraturto e +125C for 1000 cycles) Temperature 40C to +125C R/R -<1% Operating Temperature -40C to +125C General Note IRC reserves the right to make changes in product specification without notice or liability. All information is subject to IRC's own data and is considered accurate at time of going to print. NoteTechnologies Division s 3OUTH 3TAPLES 3TREET s #Orpus Christi TeXAS 53! Wire and Film General General Note Telephone: s Facsimile: make swithout Website: www.irctt.com IRC reservesTT theelectronics right to make changes inthe product specifi cation notice liability. specification without notice or liability. reserves right to changes in or product All information subject to IRC'sisown data and accurate at time goingistoconsidered print. Allis information subject to isTTconsidered electronics' own dataofand accurate at time of going to print. Wire and Film Technologies Division s 3OUTH 3TAPLES 3TREET s #Orpus Christi TeXAS 53! Telephone: s Facsimile: plc s Website: www.irctt.com (c) TT electronics A subsidiary of TT electronics plc O!2 3Eries Issue JUNE 3HEET OF A subsidiary of TT electronics plc www.bitechnologies.com www.irctt.com www.welwyn-tt.com O!2 3Eries Issue JUNE 3HEET OF 09. 11 OAR Open Air Resistor OpenElement Air Resistor Metal Current Sense Metal Element OAR Series Current Sense Physical Data On lower ranges stand-off may be eliminated NOTE: Contact factory for: 1. Variations of "A" dimension. 2. Different lead diameter. B C E F A Test Point (Kelvin connection) Dimensions (Inches and (mm)) IRC Type OAR-1 OAR-3 OAR-5 A B C E F 0.450 +0.040/-0.020 0.27 Typ 0.125 0.030 0.065 +0.010/-0.005 0.040 0.002 (11.43 +1.020/-0.508) 0.32 (8.12) max (3.18 0.762) (1.65 +0.254/-0.127) (1.02 0.051) 0.600 +0.040/-0.020 0.65 Typ 0.125 0.030 0.065 +0.010/-0.005 0.040 0.002 (15.24 +1.020/0.508) 0.92 (23.4) max (3.18 0.762) (1.65 +0.254/-0.127) (1.02 0.051) 0.800 +0.040/-0.020 0.65 Typ 0.125 0.030 0.065 +0.010/-0.005 0.040 0.002 (20.32 +1.020/-0.508) 0.88 (22.4) max (3.18 0.762) (1.65 +0.254/-0.127) (1.02 0.051) Thermal Image Data OAR-1 5 m @ 1 Watt OAR-3 5 m @ 3 Watt OAR-5 5 m @ 5 Watt Hot Spot: 87C Solder Joint: 45C Hot Spot: 160C Solder Joint: 70C Hot Spot: 230C Solder Joint: 96C The thermal images (not simulations) above are of the OARs products at their respective power rating. Notice the solder joint temperature is much lower than the hotspot. The unique construction of the OAR isolates the temperature of the hotspot from the circuit board material preventing damage to the circuit board. 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. The test conditions were in ambient temperature conditions, approximately 72 C with no forced air. Contact IRC for more details or for other thermal image test data for specific resistance values and power levels. Wire and Film Technologies Division s 3OUTH 3TAPLES 3TREET s #ORPUS #HRISTI TEXAS 53! TELEPHONE: s FACSIMILE: s WEBSITE: WWWIRCTTCOM O!2 3ERIES )SSUE JUNE 3HEET OF 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 OAR Open Air Resistor Open Air Resistor Metal Element Current Sense Metal Element Current Sense OAR Series Power Derating The typical power derating curves are based on conservative design concepts that extend from film based products. The OAR is a solid metal alloy construction that can withstand comparably greater operating power levels than conservative design models permit. Typically the resistive alloys can withstand temperatures in excess of 300C. Therefore, system thermal design considerations are a more significant design parameter due to the heat limitations of solder joints and/or circuit board substrate materials. 1400 1400 600 1200 1200 500 400 300 200 100 Surge Current (Amps) 700 Surge Current (Amps) Surge Current (Amps) Pulse/Surge Chart @ 50 msec duration 1000 800 600 400 200 0 10 20 30 40 50 60 70 80 90 100 800 600 400 200 0 0 1000 0 0 10 20 Resistance (milli-ohms) 30 40 50 60 70 Resistance (milli-ohms) OAR-1 OAR-3 80 90 100 0 5 10 15 20 25 30 35 40 45 50 Resistance (milli-ohms) OAR-5 The Surge current charts are approximations of the capabilities of the OAR product and should not be used to the exclusion of actual testing. The relative high surge currents depicted in the charts are as a result of the robust all metal welded construction and the heat carrying capability of metal. Additionally the OAR resistive wire provides large relative cross section for current flow as compared to other resistor technologies, such as thin film, thick film, or metal strip. Ordering Data Sample Part No. OAR 1 R100 F LF IRC Style OAR Power Rating in Watts 1 = 1W, 3 = 3W, 5 = 5W Resistance Range `R' indicates decimal point location Tolerance F = 1%, G = 2%, J = 5% RoHS Indicator LF indicates RoHS compliance Blank indicates Sn/Pb terminal tinning; available on special request Wire and Film Technologies Division s 3OUTH 3TAPLES 3TREET s #ORPUS #HRISTI TEXAS 53! TELEPHONE: s FACSIMILE: s WEBSITE: WWWIRCTTCOM O!2 3ERIES )SSUE JUNE 3HEET OF 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