WILLOW USR4

USR 4-1414
• Highest Stability
• Near Temperature
Independency
• Lowest Tolerances
• Low Capacitance and
Inductance
• Customized Resistance Values
SPECIFICATIONS
ELECTRICAL
Resistance Range
:
0R5 ...100R
Power Rating
:
0.8 W without heatsink (70°C)
25 W with heatsink
Thermal Resistance Rthj-c :
< 4.2 K/W
Tolerances
from 0R5
from 1R
:
:
:
0.1%, 0.25%, 0.5%, 1%
0.01%, 0.05%, 0.1%, 0.25%, 0.5%, 1%
Stability
:
0.01%
Temperature Coefficient :
max. ±5 ppm/K (-55...155)°C
typ. ±3 ppm/K (-55...125)°C
upon request ±1 ppm/K (0...60)°C
Voltage Proof
:
1.5 kVDC
Thermal EMF
:
< 1 µV/K
ENVIRONMENTAL
Operating Temperature Range :
MECHANICAL
Resistor Material
Substrate
Housing
Connector Material
:
:
:
:
-55°C...155°C
NiCr-Foil
Al2O3 (upon request AlN)
Plastic + Epoxy
Cu-tinned / 4-pin
Willow Technologies Ltd. Shawlands Court, Newchapel Road, Lingfield, Surrey, RH7 6BL, UK
Tel. + 44 (0) 1342 835234, Fax. + 44 (0) 1342 834306, e-mail [email protected] web www.willow.co.uk
USR 4-1414
TEMPERATURE COEFFICIENT
600
+5 ppm/K
dR/R (ppm )
400-5 ppm/K
200
No minal-Spread
+/-2,3 ppm/K
0
+2,2 ppm/K
-200
-1,8 ppm/K
No minal-dR/R
-400
No minal-Spread
+/-2,3 ppm/K
-600
-50
-25
0
25
50
100
75
125
Tem perature (°C)
DERATING CURVE
without heatsink
with heatsink
120
80
Power ( % from
nominal power)
pow er (% from
nom inal pow er)
100
60
40
20
0
100
80
60
40
20
0
25
40
55
70
85 100 115 130 145 155
25
Ambient Temperature (°C)
50
85
100
115
130
145
Temperature of the backplate (°C)
DIMENSIONS
Dimensions in mm
HOW TO ORDER
USR 4-1414 1R5 0.1% TK3
USR 4-1414 0R1 0.1% TK3
Willow Technologies Ltd. Shawlands Court, Newchapel Road, Lingfield, Surrey, RH7 6BL, UK
Tel. + 44 (0) 1342 835234, Fax. + 44 (0) 1342 834306, e-mail [email protected] web www.willow.co.uk
155