PF1260 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 20W Free Air 2 1W Thermal Resistance Resistance Range Min 5.9K/W 0.01W 3 Max 51KW Tolerances Temperature Coefficients ±1% ( R ≥0.1W ) ±5% ±50ppm/°C ( R ≥10W ) ±100ppm/°C ( 0.1W ≤ R < 10W ) ±250ppm/°C ( R < 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 : PF1262 Dielectric Strength 2000 VAC Max. Operating Voltage 500 V Insulation Resistance >1000 Meg-Ohm Environmental Performance DR Test Conditions Load Life ±1% + 0.05W 25°C / 90 min ON / 30 min OFF / 1000 hr Humidity Resistance ±1% + 0.05W 40°C / 90-95% RH / DC 0.1W / 1000 hr Temperature Cycle ±0.25% + 0.05W -55°C for 30 min / +155°C for 30 min / 1000 hr Solder Heat ±0.1% + 0.05W +350°C / 3s Vibration ±0.25% + 0.05W IEC60068-2-6 Ordering Information Part Description: Part Type - Resistance - Tolerance Example: PF1262 0.5 Ohm 1% Riedon Inc. 300 Cypress Avenue 07/13 Alhambra CA 91801 (626) 284-9901 (626) 284-1704 www.riedon.com PF1260 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 To specify an appropriate heatsink use the following formula : 12 60 62 40 RqH = TMAX - ( P x RqR ) - TA P 20 0 -25 0 25 50 75 100 125 150 Backplate Temperature (°C) 175 Where: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 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. 300 Cypress Avenue 07/13 Alhambra CA 91801 (626) 284-9901 (626) 284-1704 www.riedon.com