LOB SERIES
LOW RESISTANCE METAL ELEMENT RESISTOR
•
•
•
•
•
•
•
Ultra low resistance values (0.005Ω to 0.1Ω)
Available in 1-watt, 3-watt and 5-watt rated packages
Tolerances from ±1% to ±5%
Inherently non-inductive (≤.02µh @ 0.5MHz)
Low temperature coefficient of resistance
High stability over life
Lead free ROHS compliant construction available
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.
DESCRIPTION:
APPLICATIONS:
•
Switchmode and linear power
supplies.
•
Automotive current-sensing
circuits
•
Instrumentation
•
Regulators
LOBΩ Series resistors feature
tinned copper leads welded directly
to a low-temperature coefficient
resistance element in a highly au-
tomated proprietary process. The
leaded resistor elements are then
encapsulated in a molding com-
LOB-1
1
5
√1xR
175
LOB-3
3
15
√3xR
175
LOB-5
5
25
√5xR
175
Units
Watts
Watts
Volts
°C
CONSTRUCTION:
CHARACTERISTIC
Continuous power dissipation @ 25°C in free air
Overload power for 5 seconds
Maximum working voltage
Maximum storage temperature
ABSOLUTE MAXIMUM RATINGS:
*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, and must be taken into account when
GENERAL SPECIFICATIONS - ENVIRONMENTAL TESTING*:
TEST PARAMETERS
Load Life (2,000 hours)
Thermal Shock
Vibration
Mechanical Shock
Dielectric Strength
Insulation Resistance
MIL-STD 202
Method 108
Method 107
Method 204
Method 213
Method 301
Method 302
MAX %∆R *
±1%
±1%
±0.5%
±0.5%
±0.5%
>10
11
Unit
%∆R
%∆R
%∆R
%∆R
%∆R
Ohms
*±0.0005 ohm allowance for test/contact error.
General Note
IRC reserves the right to make changes in product specification without notice or liability.
All information is subject to IRC’s own data and is considered accurate at time of going to print.
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WIREWOUND AND FILM TECHNOLOGIES DIVISION
736 Greenway Road • Boone, North Carolina 28607-1860 • Tel: 828-264-8861 • Fax: 828-264-8866 • www.irctt.com
A subsidiary of
TT electronics plc
LOB DIMENSIONS
(Inches and (mm)):
Style
LOB-1
LOB-3
LOB-5
connect
point
L
0.390 ±0.010
(9.9 ±0.3)
0.560 ±0.010
(14.224 ±0.254)
0.920 ±0.010
(23.368 ±0.254)
D
0.140 ±0.008
(3.6 ±0.2)
0.210 ±0.010
(5.334 ±0.254)
0.330 ±0.010
(8.382 ±0.254)
C
C
1.31
(33.274)
1.31
(33.274)
1.670
(42.418)
I
1.50 ±0.125
(38.1 ±3.2)
1.375 ±0.125
(34.925 ±3.175)
d
0.0305 ±0.002
(0.813 ±0.051)
0.0305 ±0.002
(0.813 ±0.051)
1.250 ±0.125
0.040 ±0.002
(31.750 ±3.175)
(1.016 ±0.051)
connect
point
d
I
L
D
POWER DERATING PERCENTAGE VS.
FREE AIR AMBIENT TEMPERATURE:
TEMPERATURE COEFFICIENT OF
RESISTANCE VS. RESISTANCE VALUE:
Temperature Coefficient of Resistance
(ppm/°C)
rewoP detaR egatnecreP
Ambient Temperature (°C)
LOB-1
LOB-3
LOB-5
Resistance (ohms
X
10
-3
)
HOW TO ORDER:
To order, specify style, resistance value, tolerance and package type as in the following example:
LOB-3 0.01Ω 1% LF LT
StylePackaging
LT (Lead Tape) 500 pcs. min.
LOB-1 (1 watt)
LOB-3 (3 watt)
LOB-5 (5 watt)
Resistance Value
0.005Ω 0.02Ω
0.04Ω
0.01Ω
0.025Ω 0.05Ω
0.015Ω 0.03Ω
0.07Ω
0.08Ω
0.1Ω
Contact factory for other values
Packaging
LT (Lead Tape) 500 pcs. min.
LOB-1 3500pcs. max
LOB-3 1250 pcs. max.
LOB-5 800 pcs. max.
BLK (Bulk Pack) 500/box
packed loose in box
Tolerance
5%, 3%, 1% - All styles/values
General Note
Lead-Free Construction
IRC reserves the right to make changes in product specification without notice or liability.
All information is subject to IRC’s own data and is considered accurate at time of going to print.
WIREWOUND AND FILM TECHNOLOGIES DIVISION
736 Greenway Road • Boone, North Carolina 28607-1860 • Tel: 828-264-8861 • Fax: 828-264-8866 • www.irctt.com
A subsidiary of
TT electronics plc
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