PF1262 Series TO-126 Power Thin Film Resistors • • • • • • • TO-126 Housing Resistances from 0.01 to 51K Ohms Rated Power to 20 Watts Resistance Tolerances to ±1% TCR to ±50ppm/°C Low Inductance ( <50nH ) Isolated Back Plate SPECIFICATIONS Type Power Rating Heatsink PF1262 1 2 Free Air 20W 1W Resistance Range Thermal Resistance Min 5.9K/W 0.01Ω 3 Max 51KΩ Tolerances Temperature Coefficients ±1% ( R ≥0.1Ω ) ±5% ±50ppm/°C ( R ≥10Ω ) ±100ppm/°C ( 0.1Ω ≤ R < 10Ω ) ±250ppm/°C ( R < 0.1Ω ) 1 Power rating based on 25°C Flange Temperature Power rating based on 25°C Ambient Temperature 3 Consult Factory for Higher or Lower Values 2 Specification Value Maximum Current 25A Temperature Range -55°C to +155°C : PF1262 Dielectric Strength 2000 VAC Max. Operating Voltage 500 V Insulation Resistance >1000 Meg-Ohm Environmental Performance ∆R Test Conditions Load Life ±1% + 0.05Ω 25°C / 90 min ON / 30 min OFF / 1000 hr Humidity Resistance ±1% + 0.05Ω 40°C / 90-95% RH / DC 0.1W / 1000 hr Temperature Cycle ±0.25% + 0.05Ω -55°C for 30 min / +155°C for 30 min / 1000 hr Solder Heat ±0.1% + 0.05Ω +350°C / 3s Vibration ±0.25% + 0.05Ω IEC60068-2-6 Ordering Information Part Description: Part Type - Resistance - Tolerance Example: PF1262 0.5 Ohm 1% Riedon Inc. 08/14 300 Cypress Avenue Alhambra CA 91801 www.riedon.com (626) 284-9901 (626) 284-1704 PF1262 Series TO-126 Power Thin Film Resistors SPECIFICATIONS (continued) Power Derating Curve Power Rating Notes - 120 The PF1260 Series Thin Film Resistors must be attached to a suitable heatsink. The maximum internal resistor temperature is 155°C. Power ( % ) 100 80 PF 12 60 To specify an appropriate heatsink use the following formula : 62 40 RθH = TMAX - ( P x RθR ) - TA P 20 0 -25 0 25 50 75 100 125 150 175 Where: Backplate Temperature (°C) RθH = Thermal Resistance of Heatsink ( K/W ) RθR = 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 PF1260 Series Thin 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 ). Back plate is isolated from both pins. Riedon Inc. 08/14 300 Cypress Avenue Alhambra CA 91801 www.riedon.com (626) 284-9901 (626) 284-1704