Metal Strip Current Sense Resistors Surface Mount Welwyn Components ULR Series • • • • 1 watt to 3 watts, all 2512 size • RoHS compliant Resistance R0005 (0.5mΩ) to R01 (10mΩ) Low TCR, Low inductance Designed for current sensing in power electronic systems Electrical Data ULR1 ULR2 ULR25 ULR3 Power rating at 80°C watts 1.0 2.0 2.5 3.0 Resistance range ohms R0005 to R007 R0005 to R01 R0035 to R006 R0005 to R003 volts 200V 200V 200V 200V 50, 75, 100, 150 See table below 50 50 50, 75, 100 See table below Black Green/ Black Green Green 1 Isolation voltage TCR ppm/°C Resistance Tolerance Protective coating % 1(F), 5(J) 2 Standard Values See table below for available values Ambient temperature range °C -55 to +170 Note 1: For values above 0R01 refer to our LR / LRF Series Note 2: Colour of coating relates to solder process suitability, see Construction Standard Values Available (non-standard values may be available to order - consult factory) ULR1 ULR2 ULR25 Value Colour TCR Colour TCR R0005 Black 50 Black R00075 Black 50 R001 Black R0015 R002 Colour ULR3 Colour TCR 50 Green 100 Black 50 Green 100 50 Black 50 Green 50 Black 50 Black 50 Green 50 Black 50 Black 50 Green 50 R0025 Black 150 Green 75 R003 Black 150 Green 75 R0035 Black 150 Green TCR 50 R004 Black 100 Green 50 R0045 Black 100 Green 50 R005 Black 100 Green 50 R0055 Black 100 Green 50 R006 Black 75 Green 50 R007 Black 75 Green 50 R008 Green 50 R009 Green 50 R01 Green 50 General Note Welwyn Components reserves the right to make changes in product specification without notice or liability. All information is subject to Welwyn’s own data and is considered accurate at time of going to print. A subsidiary of TT electronics plc © Welwyn Components Limited · Bedlington, Northumberland NE22 7AA, UK Telephone: +44 (0) 1670 822181 · Facsimile: +44 (0) 1670 829465 · Email: [email protected] · Website: www.welwyn-tt.com Issue A · 09.06 Metal Strip Current Sense Resistors Surface Mount Welwyn Components ULR Series Construction Black type A low TCR resistance alloy plate, with plated connection bands is protectively coated and numerically marked with the resistance value. This part has standard plated end connections and is suitable for wave or IR reflow soldering. Green type A low TCR resistance alloy plate is grooved to set the final resistance, the lower faces are solder plated for connections, and it is protectively coated and numerically marked with the resistance value. This part is ONLY suitable for IR reflow soldering. Sn Plated Finish Cn Plating Ally Plate Protective Coating Black Type Protective Coating Metal Strip Marking For values which are integer numbers of milliohms, the marking is 4-character IEC62 code; e.g. “R002” for 2mΩ, “R010” for 10mΩ. For values including fractions of a milliohm the marking is 3 or 4character code using “M” to indicate the decimal point, e.g. “M75” for 0.75mΩ, “1M50” for 1.5mΩ. Sn Plated Finish Green Type Termination Details: Material Matt tin plated finish over a barrier layer Solderability 95% min coverage (MIL-STD 202F / 208H, 235ºC 2 secs) Performance Data Maximum ∆R% ±1% + 0.5mΩ (Black): ±1% (Green) Short term overload (5 x rated power for 5s) ∆R% ±0.5% + 0.5mΩ (Black): ±1% (Green) Dry heat (96Hrs, no load, +155°C) ∆R% ±1% + 0.5mΩ (Black): ±1% (Green) Temperature rapid change (-55 / +150ºC, 100 cycles) ∆R% ±0.5% + 0.5mΩ (Black): ±1% (Green) Resistance to solder heat (260ºC for 10s) ∆R% ±0.5% + 0.5mΩ (Black): ±1% (Green) Load at rated power (1000hrs cyclic load at 70°C) De-rating from rated power at 80°C See Graph Power de-rating graph P 100% 50% T°C 0% -55 0 80 © Welwyn Components Limited Bedlington, Northumberland NE22 7AA, UK Telephone: +44 (0) 1670 822181 · Facsimile: +44 (0) 1670 829465 · Email: [email protected] · Website: www.welwyn-tt.com 170 Issue A · 09.06 Metal Strip Current Sense Resistors Surface Mount Welwyn Components ULR Series Recommended Solder Pad Layout 1.8 1.8 4.75 4.75 1.45 3.6 0.7 2-wire pad layout 4-wire pad layout (recommended for precision current sensing) Dimensions (mm) Type Values (mΩ) L W T D Nom. Wt. (g) Green 0.5mΩ, 0.75mΩ 6.35 3.18 1.00 1.93 0.09 Green 1mΩ to 10mΩ 6.35 3.18 0.60 1.93 0.08 Black 0.5mΩ 6.35 3.18 1.40 1.30 0.06 Black 0.75mΩ 6.35 3.18 1.00 1.30 0.06 Black 1mΩ 6.35 3.18 0.80 1.30 0.06 Black 1.5mΩ 6.35 3.18 0.65 1.30 0.06 Black 2mΩ 6.35 3.18 0.50 1.30 0.06 Black 2.5mΩ 6.35 3.18 1.00 1.30 0.06 Black 3mΩ 6.35 3.18 0.70 1.30 0.06 Black 3.5mΩ 6.35 3.18 0.71 1.30 0.06 Black 4mΩ 6.35 3.18 0.60 1.30 0.06 Black 4.5mΩ 6.35 3.18 0.58 1.30 0.06 Black 5mΩ 6.35 3.18 0.50 1.30 0.06 Black 5.5mΩ 6.35 3.18 0.47 1.30 0.06 Black 6mΩ 6.35 3.18 0.50 1.30 0.06 Black 7mΩ 6.35 3.18 0.45 1.30 0.06 D W L T Flammability The resistor will not burn or emit incandescent particles under any condition of applied temperature or overload. Solvent resistance The body protection and marking are resistant to all normal industrial solvents suitable for printed circuits. Packaging The standard packing for ULR parts is on a 2000 piece reel of size 12mm tape Ordering Procedure Example: ULR2 at 2.5 milliohms and 1% tolerance on reel of 2000 pieces: Type ULR2 - R0025 F T2 Resistance value (IEC62 code) Tolerance (IEC62 code) F 1% J 5% Packing T2 © Welwyn Components Limited Bedlington, Northumberland NE22 7AA, UK Telephone: +44 (0) 1670 822181 · Facsimile: +44 (0) 1670 829465 · Email: [email protected] · Website: www.welwyn-tt.com Tape 2512 2000 / reel Issue A · 09.06