PF1260 Series
TO-126 Power Film Resistors
SPECIFICATIONS
(continued)
Power Derating Curve
120
100
Power Rating Notes -
The PF1260 Series Film Resistors must be attached to a suit-
able heatsink. The maximum internal resistor temperature is
155°C.
To specify an appropriate heatsink use the following formula :
Power ( % )
80
60
40
20
0
PF
12
62
R
qH
= T
MAX
- ( P x R
qR
) - T
A
P
125
150
175
-25
0
25
50
75
100
Ambient Temperature (°C)
Where:
R
qH
= Thermal Resistance of Heatsink ( K/W )
R
qR
= Thermal Resistance of Resistor ( K/W )
T
MAX
= Maximum Temperature of Resistor
T
A
= Ambient Temperature of Heatsink ( °C )
P = Power Through Resistor ( W )
Mounting Notes -
The PF1260 Series Film Resistors must be attached to a suit-
able 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.
Ordering Information
Part Number - Resistance - Tolerance - TCR
Example: PF1262 0.5 Ohm 1% 100ppm
Riedon Inc.
03/11
300 Cypress Avenue
Alhambra CA 91801
(626) 284-9901
(626) 284-1704
RIEDON [ RIEDON POWERTRON ]
