Surface Mount Power
PꢀꢄFOꢄMꢁNCꢀ dꢁꢂꢁ
Temp. cycle
(-55°C to 125°C, (1000 hours
1000 cycles) at 25°C)
Load Life
Immersion
(260°C for
10 sec.)
Derating
Momentary
Overload
100
80
60
40
20
0
Construction
RC Carbon/Ceramic Comp.
RF Metal Film
RW Wirewound
±4.0%+.05Ω ±10.0%+.05Ω ±3.0%+.05Ω 6.3x rated power for 5 sec.
±0.5%+.05Ω ±0.5%+.05Ω ±0.1%+.05Ω 2x rated power for 0.1 sec.
±0.5%+.05Ω ±3.0%+.05Ω ±0.1%+.05Ω 5x rated power for 5 sec.
±3.0%+.05Ω ±5.0%+.05Ω ±0.5%+.05Ω 2x rated power for 0.1 sec.
RP Power Film
RN Wirewound, Non-inductive ±0.5%+.05Ω ±3.0%+.05Ω ±0.1%+.05Ω 5x rated power for 5 sec.
ALL models:
Leaching (260°C Solder immersion, 60 sec.).......................
Thermal Shock (Units at -55°C, then rated power applied)..
Flammability ......................................................................... UL Material rating, UL94V0
No visible leaching
No mechanical damage
0
25
50
75 100 125 150
Ambient Temperature, ϒC
TCR
Recommended Solder Profile
300
500
400
300
200
100
Preheating: 145°C ±15°, max. 120 sec.
Soldering: min. 220°C, max. 60 sec.
Max. Temp.: 260°C ±5°, 10 sec.
Soldering
10 sec.
250
Typical TCR for
less than 0.1Ω SMD
resistors (PPM/°C)
60 sec.
200
Preheating
Cooling
120 sec.
150
100
50
0
0
50 100 150 200 250
Time (sec.)
0.02 0.04 0.06 0.08 0.10
Ohms
200
The temperature rise graph
data was obtained by a
selection of test substrate
size and trace width for
each resistor size to limit
operating temperatures to
safe values.
Package limit hot spot temperature rise
180
160
140
120
100
80
Alumina
FR4
The operating temperature
safe rises are either 100°C
substrate temperature rise
or 180°C package hot spot
temperature rise at 25°C
ambient.
FR4: 0.062 in. thick; 0.062
in. traces
60
40
Alumina: 0.040 in. thick;
0.010 in. traces
Solder joint
20
Molding material rated at
205°C continuous.
100%
200%
300%
Percent Rated power
ꢄC SꢀꢄIꢀS: bꢁkꢀ PꢄOCꢀdꢃꢄꢀ
RC SERIES ONLY A. Heat Treatment
B. Frequency of C. Cautions
heat treatment
110°C ±10°C
15 hours
Solderability: may be affected due to oxidization of lead wire
Resistance value: some units may not completely recover to origi-
1 time only
nal value.
Soldering heat: some treated product may have substantial resis-
tance change during soldering operation. It is recommended that
parts be tested to evaluate soldering heat effects.
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