NPR NPP 2-T126 TO-126 Power Film Resistors • • • • • • • Resistances from 0.01 to 51K Ohms Power Rating to 20Watt Resistance Tolerances to ±0.05% TCR to ±5ppm/K TO-126 Housing Convenient SMD DPak Available Low Inductance ( <50nH ) SPECIFICATIONS Type NPR 2-T126 NPP 2-T126 Power Rating Heatsink1 Free Air2 20W 1W 5W 0.5W Resistance Range3 Thermal Resistance Tolerances Temperature Coefficients 51KW ±1% ( R > 0.1W ) ±5% ±50ppm/K ( R>10W ) ±100ppm/K ( R>0.1W ) ±250ppm/K 51KW ±0.05% / ±0.1% / ±0.25% ( R > 5W ) ±0.5% ( R > 1W ) / ±1% ( R > 0.1W ) ±2% / ±5% ±5 / ±10ppm/K ( R>1W ) ±25ppm/K ( R >0.1W ) ±100ppm/K Min Max 5.9K/W 0.01W 6.0K/W 0.1W Power rating based on 25°C Flange Temperature Power rating based on 25°C Ambient Temperature 3 Consult Factory for Higher or Lower Values 1 2 Specification Value Maximum Current 25A Temperature Range -55°C to +155°C : NPP 2T126 -55°C to +120°C : NPR 2-T126 Dielectric Strength 2000 VAC Max. Operating Voltage 500 V Insulation Resistance >1000 Meg-Ohm Environmental Performance DR Test Conditions Load Life ±1% 25°C / 90 min ON / 30 min OFF / 1000 hr ±1% 40°C / 90-95% RH / DC 0.1W / 1000 hr Humidity Resistance Temperature Cycle ±0.25% -55°C for 30 min / +155°C for 30 min / 1000 hr Solder Heat ±0.1% +350°C / 3s Vibration ±0.25% Riedon Inc. 1.01 300 Cypress Avenue Alhambra CA 91801 (626) 284-9901 (626) 284-1704 www.riedon.com Page 78 NPR NPP 2-T126 TO-126 Power Film Resistors SPECIFICATIONS (continued) Power Rating Notes - Power Derating Curve The NPR 2-T126 Series Foil Resistors must be attached to a suitable heatsink. The maximum internal resistor temperature is 155°C (120°C for the NPP 2-T126). 120 Power ( % ) 100 80 60 R P 40 20 0 NP NP 2- To specify an appropriate heatsink use the following formula : 2-T RqH = TMAX - ( P x RqR ) - TA P 12 T1 6 26 Where: -25 0 25 50 75 100 125 150 Ambient Temperature (°C) 175 RqH = Thermal Resistance of Heatsink ( K/W ) RqR = Thermal Resistance of Resistor ( K/W ) TMAX = Maximum Temperature of Resistor TA = Ambient Temperature of Heatsink ( °C ) P = Power Through Resistor ( W ) Mounting Notes The NPR 2-T126 Series Film Resistors must be attached to a suitable heatsink. Mount resistor using thermal grease to a clean / flat surface. Use a compression washer to provide 150 to 300 pounds ( 665 to 1330N ) of mounting force. Torque mounting screw to 8 in-lbs ( 0.9 Nm ). Ordering Information Part Number - Resistance - Tolerance - TCR Example: NPR 2-T126 0.5 Ohm 1% 100ppm Riedon Inc. 1.01 300 Cypress Avenue Alhambra CA 91801 (626) 284-9901 (626) 284-1704 www.riedon.com Page 79