Low Resistance Metal
Element Resistors
LOB Series
Welwyn Components
•
Ultra low resistance values
(0.005Ω to 0.1Ω)
•
Available in 1, 3 and 5 watt rated packages
•
Tolerances from ±1% to ±5%
•
Inherently non-inductive (≤.02µH at 0.5MHz)
•
Low temperature coefficient of resistance
•
High stability over life
Electrical Data
LOB-1
Continuous power dissipation at 25°C in free air
Overload power for 5 seconds
Maximum working voltage
Maximum storage temperature
watts
watts
volts
°C
1
5
√1xR
175
LOB-3
3
15
√3xR
175
LOB-5
5
25
√5xR
175
* Power Dissipation - The maximum wattage rating depends upon the amount of heat which can be transferred to the surroundings while not exceeding the maximum element
temperature. Ambient air temperature, velocity of cooling air, thermal resistance of heat and the temperature of surrounding objects will affect this transfer, this must be taken
into account when selecting a resistor.
Physical Data
Dimensions (mm)
contact point
Type
LOB-1
L max.
9.9±0.3
D max.
3.6±0.2
f min.
38.1±3.2
d nom.
0.813±0.05
C
33.27
33.27
42.42
d
D
C
contact point
LOB-3
14.22±0.25 5.33±0.25 34.93±3.18 0.81±0.05
LOB-5
23.37±0.25 8.38±0.25 31.75±3.18 1.02±0.05
L
f
Description
LOBΩ Series power precision metal element resistors feature
resistance values down to 0.005Ω with virtually no
inductance. Available in 1, 3 and 5 watt rated axial leaded
packages, these resistors are compatible with automatic
insertion equipment.
Construction
LOBΩ Series resistors feature tinned copper leads welded
directly to a low temperature coefficient resistance element in
a highly automated proprietary process. The leaded resistor
elements are then encapsulated in a moulding compound.
Applications
•
•
•
Switchmode and linear power supplies.
Automotive current-sensing circuits.
Instrumentation.
General Note
Welwyn Components reserves the right to make changes in product specification without notice or liability.
All information is subject to Welwyn’s own data and is considered accurate at time of going to print.
A subsidiary of
TT electronics plc
Issue B · 03.02
© Welwyn Components Limited
· Bedlington, Northumberland NE22 7AA, UK
Telephone: +44 (0) 1670 822181 · Facsimile: +44 (0) 1670 829465 · Email: info@welwyn-tt.com · Website: www.welwyn-tt.com
104
WELWYN [ WELWYN COMPONENTS LIMITED ]
