Resistors
Make Possible
Open Air Resistor
Metal
OAR Element Current Sense
Open
AirSeries
Resistor
OAR
& OAR-TP
Metal
Element
Power ratings
of 1, 3, & Current
5W @ 85°C Sense
•
•
•
•
•
Superior surge performance
TCR’s
to ±20ppm/°C
Hot spot
isolated from PCB material
Power
ratings
of 1,TCR
3, & ±20ppm/°C
5W @ 85°C
Resistance wire
Resistance range from 2.5mΩ to 100mΩ
Tolerances to 1%
Open air design maximizes thermal performance
Pb-free
version is RoHS compliant
Welded copper leads minimize effects from solder wicking and provide
All Pb-free parts comply with EU Directive 2011/65/EU (RoHS2)
true 1% performance
Electrical Data
Part
Number
Power Rating
@ 85°C
(watts)
OAR-1 (TP)
1.0
OAR-3 (TP)
3.0
OAR-5 (TP)
5.0
Resistance
Range (mΩ)
Tolerance
(±%)
Wire TCR
(±ppm/°C)
Inductance
(nH)
3, 5, 6, 8, 10, 12, 15, 20, 25, 30, 35,
40, 50, 60, 70, 80, 100
2, 2.5, 3, 4, 5, 6, 7, 10, 15, 20, 25,
30, 40, 45, 50, 60, 70, 100
3, 4, 5, 6, 6.2, 10, 12, 15,
20, 25, 30, 40, 50
1, 2¹, 5
20
<10
Notes:
¹ ±2% tolerance available <5m Ω
Please contact factory for resistance values not listed
Environmental Data
Load Life (1000 hours @ 25°C)
∆R/R <1%
Moisture (no load for 1000 hours)
∆R/R <1%
Temperature Cycling (-40°C to +125°C for 1000 cycles)
∆R/R <1%
Operating Temperature
-40°C to +125°C
General Note
General Note
TT
thechanges
right toin make
in without
product
specification
IRCElectronics
reserves the reserves
right to make
productchanges
specification
notice
or liability. without notice or liability.
All information
is subject
to IRC’s
data and is considered
accurate
at considered
time of going to
print.
All
information
is subject
to own
TT Electronics’
own data
and is
accurate
at time of going to print.
Wire and Film Technologies Division • 4222 South Staples Street • Corpus Christi Texas 78411 USA
©
TT Electronics
Telephone:
361 992 7900 plc
• Facsimile: 361 992 3377 • Website: www.irctt.com
A subsidiary of
www.ttelectronicsresistors.com
TT electronics plc
OAR Series Issue June 2011 Sheet 1 of 3
11.14
OAR
Open Air Resistor
Open
Air Resistor
Metal
Element
Current Sense
Metal
Element
OAR
& OAR-TP
Series
Make Possible
Current Sense
OAR
Open
Air
Resistor
Physical
Data
Physical
Data
Metal Element Current Sense
On lower ranges stand-off may be
eliminated
NOTE:
Contact factory for:
1. Variations of “A” dimension.
2. Different lead diameter.
B
Physical Data
C
E
On lower ranges stand-off may be
eliminated
F
Test Point (Kelvin connection)
A
B
Type
A
IROAR1
C Type
0.45 +0.04/-0.02
A
(11.43 +1.02/-0.51)
IRC Type
OAR3TP
OAR-5
<R005
OAR-1
OAR3TP
≥R005
OAR-3
B0.32 (8.12)
0.450 +0.040/-0.020
0.27 Typ
0.197 +0.04/-0.03
(11.43 (5.0
+1.020/-0.508)
+1.0/-0.8)
OAR-1
OAR1TP
OAR3
OAR-3
B max
Dimensions
(Inches andC(mm))
0.3max
(7.8)
0.32 (8.12)
OAR5TP
C
E
E
F
0.125 ±0.030
F
0.065 +0.010/-0.005
0.040 ±0.002
(3.18 ±0.762)
(1.65 +0.254/-0.127)
(1.02 ±0.051)
A
Test Point (Kelvin connection)
0.6000.60
+0.040/-0.020
0.65
Typ
0.125 ±0.030
0.065 +0.010/-0.005
+0.04/-0.02
Dimensions
0.92 (23.4) (Inches and (mm))
(15.24
+1.02/-0.51) 0.92 (23.4) max
(15.24
+1.020/0.508)
(3.18 ±0.762)
(1.65 +0.254/-0.127)
0.065
+0.01/-0.005
A
B
C 0.125 ±0.03
E
+0.04/-0.03
0.8000.275
+0.040/-0.020
0.65 Typ
0.125 ±0.030
(3.18 ±0.76) 0.065 +0.010/-0.005
(1.65 +0.25/-0.13)
0.450 +0.040/-0.020
0.27 Typ
0.125 ±0.030
0.065 +0.010/-0.005
(7.0 +1.0/-0.8)
(20.32 +1.020/-0.508) 0.88 (22.4)
(1.65 +0.254/-0.127)
1.0 max
(25.4) (3.18 ±0.762)
(11.43 +1.020/-0.508)
0.32
(8.12)
max
(3.18
±0.762)
(1.65
+0.254/-0.127)
0.197 +0.04/-0.03
(5.0 +1.0/-0.8)
0.600 +0.040/-0.020
0.125 ±0.030
0.065 +0.010/-0.005
0.040 ±0.002
(1.65 +0.254/-0.127)
(1.02 ±0.051)
0.800 +0.040/-0.020
0.275 +0.04/-0.03
(20.32 +1.020/-0.508)
(7.0 +1.0/-0.8)
0.65 Typ
0.040 ±0.002
(1.02 ±0.051)
F0.04 ±0.002
0.040
±0.002
(1.02
±0.05)
0.040 ±0.002
(1.02 ±0.051)
(1.02 ±0.051)
0.80 +0.04/-0.02 0.92 (23.4) max
(15.24 +1.020/0.508)
0.88 (22.4) (3.18 ±0.762)
(20.32 +1.02/-0.51)
Thermal
Image Data
OAR5
OAR-5
E
C
NOTE:
Contact factory for:
F
1. Variations of “A” dimension.
2. Different lead diameter.
0.125 ±0.030
0.065 +0.010/-0.005
0.040 ±0.002
(27.9) (3.18 ±0.762)
0.88 (22.4)1.1
max
0.65 Typ
(1.65 +0.254/-0.127)
(1.02 ±0.051)
Thermal Image Data
OAR-1 5 mΩ @ 1 Watt
OAR-3 5 mΩ @ 3 Watt
OAR-5 5 mΩ @ 5 Watt
Hot Spot:
87°C
Solder Joint: 45°C
Hot Spot:
160°C
Solder Joint: 70°C
Hot Spot:
230°C
Solder Joint: 96°C
The thermal images (not simulations) above are of the OAR products at their respective power rating. Notice the
solder joint temperature is much lower than the hotspot. The unique construction of the OAR isolates the temperaOAR-1
5 mΩ
@ 1from
Wattthe circuit board material
OAR-3 5preventing
mΩ @ 3 Watt
mΩ @ 5 Watt
ture
of the
hotspot
damage to the circuitOAR-5
board. 5Additionally,
the thermal
energy
is
dissipated
to
the
air
instead
of
being
conducted
into
the
circuit
board
potentially
causing
a
nearby
power
Hot Spot:
87°C
Hot Spot:
160°C
Hot Spot:
230°C
component
to exceed
its rating.
Solder Joint:
45°C
Solder Joint: 70°C
Solder Joint: 96°C
The
thermal
images
(not simulations)
above
of layer
the OAR
their
respective
power
rating.
The
standard
test circuit
board consists
of aare
four
FR4products
material at
with
2 ounce
(70µm)
outer
layersNotice
and 1 the
ounce
solder
joint
temperature
is much
lower of
than
theindustry
hotspot.designs.
The unique
of the
OAR
isolates temperature
the tempera(35µm)
inner
layers, which
is typical
many
Theconstruction
test conditions
were
in ambient
ture
of the hotspot
from the circuit
board
preventing
to the circuit
board.
Additionally,
the
thermal
conditions,
approximately
22 °C with
nomaterial
forced air.
Contactdamage
TT electronics
for more
details
or for other
thermal
image
energy
is dissipated
to resistance
the air instead
of being
conducted
test data
for specific
values
and power
levels.into the circuit board potentially causing a nearby power
component to exceed its rating.
Wire and Film Technologies Division • 4222 South Staples Street • Corpus Christi Texas 78411 USA
Telephone: 361 992 7900 • Facsimile: 361 992 3377 • Website: www.irctt.com
OAR Series Issue June 2011 Sheet 2 of 3
The standard test circuit board consists of a four layer FR4 material with 2 ounce (70µm) outer layers and 1 ounce
(35µm) inner layers, which is typical of many industry designs. The test conditions were in ambient temperature
conditions, approximately 22 °C with no forced air. Contact TT electronics for more details or for other thermal image
test data for specific resistance values and power levels.
Wire and Film Technologies Division • 4222 South Staples Street • Corpus Christi Texas 78411 USA
Telephone:
992 7900 • Facsimile: 361 992 3377 • Website: www.irctt.com
General361Note
TT Electronics reserves the right to make changes in product specification without notice or liability.
All information is subject to TT Electronics’ own data and is considered accurate at time of going to print.
OAR Series Issue June 2011 Sheet 2 of 3
www.ttelectronicsresistors.com
© TT Electronics plc
11.14
OAR
Open Air Resistor
Open Air Resistor
Metal Element Current Sense
Make Possible
Metal Element Current Sense
OAR & OAR-TP Series
Power Derating
The typical power derating curves are based on conservative design concepts that extend from film
based products. The OAR is a solid metal alloy construction that can withstand comparably greater
operating power levels than conservative design models permit. Typically the resistive alloys can
withstand temperatures in excess of 300°C. Therefore, system thermal design considerations are a more
significant design parameter due to the heat limitations of solder joints and/or circuit board substrate
materials.
1400
1400
600
1200
1200
500
400
300
200
100
Surge Current (Amps)
700
Surge Current (Amps)
Surge Current (Amps)
Pulse/Surge Chart @ 50 msec duration
1000
800
600
400
200
0
10
20
30
40
50
60
70
80
90
100
800
600
400
200
0
0
1000
0
0
10
20
30
40
50
60
70
80
90
100
0
5
10
15
20
25
30
35
Resistance (milli-ohms)
Resistance (milli-ohms)
Resistance (milli-ohms)
OAR-1(TP)
OAR-3(TP)
OAR-5(TP)
40
45
50
The Surge current charts are approximations of the capabilities of the OAR product and should not be
used to the exclusion of actual testing. The relative high surge currents depicted in the charts are as a
result of the robust all metal welded construction and the heat carrying capability of metal. Additionally
the OAR resistive wire provides large relative cross section for current flow as compared to other resistor
technologies, such as thin film, thick film, or metal strip.
Ordering Data
Sample Part No.
OAR
1
R100
F
LF
IRC Style
OAR
Power Rating in Watts
1 = 1W, 3 = 3W, 5 = 5W
Resistance Range
‘R’ indicates decimal point location
Tolerance
F = ±1%, G = ±2%, J = ±5%
RoHS Indicator
LF indicates RoHS compliance
Blank indicates Sn/Pb terminal
tinning; available on special request
Wire and Film Technologies Division • 4222 South Staples Street • Corpus Christi Texas 78411 USA
Telephone: 361 992 7900 • Facsimile: 361 992 3377 • Website: www.irctt.com
OAR Series Issue June 2011 Sheet 3 of 3
General Note
TT Electronics reserves the right to make changes in product specification without notice or liability.
All information is subject to TT Electronics’ own data and is considered accurate at time of going to print.
www.ttelectronicsresistors.com
© TT Electronics plc
11.14
OAR-1(TP)
OAR-3(TP)
OAR-5(TP)
The Surge current charts are approximations of the capabilities of the OAR product and should not be
used to the exclusion of actual testing. The relative high surge currents depicted in the charts are as a
Open
result ofAir
theResistor
robust all metal welded construction and the heat carrying capability of metal. Additionally
the
OAR
resistive
provides
large relative cross section for current flow as compared to otherMake
resistor
Metal Element wire
Current
Sense
Possible
technologies, such as thin film, thick film, or metal strip.
OAR & OAR-TP Series
Ordering
Data
Ordering
Procedure
Sample Part No.
OAR
1
R100
F
LF
This product has two valid part numbers:
IRC Style
OAR
European
(Welwyn) Part Number: OAR3-R01JI (OAR3, 10 milliohms ±5%, Pb-free)
Power Rating in Watts
1 = 1W, 3 = 3W, 5 = 5W
O
Resistance Range
A
R
‘R’ indicates decimal point location
3
-
1
Tolerance
R
0
2
1
3
J
I
4
5
F = ±1%, G = ±2%, J = ±5%
RoHS Indicator
LF indicates RoHS 1
compliance
Blank indicates Sn/Pb terminal
tinning; availableType
on special request
2
3
4
5
Pitch
Value
Tolerance
Packing
F = ±1%
G = ±2%
J = ±5%
I = Bulk
OAR1 Omit for standard
3-5 characters
OAR3 TP = Tight Pitch See Electrical Data
OAR5
R = ohms
Wire and Film Technologies Division • 4222 South Staples Street • Corpus Christi Texas 78411 USA
OAR Series Issue June 2011 Sheet 3 of 3
Telephone: 361 992 7900 • Facsimile: 361 992 3377 • Website: www.irctt.com
USA (IRC) Part Number: OAR3R010JLF (OAR3, 10 milliohms ±5%, Pb-free)
O
A
R
3
R
1
2
0
1
0
3
J
4
L
F
5
1
2
3
4
Type
Pitch
Value
Tolerance
Termination
F = ±1%
G = ±2%
J = ±5%
Omit for SnPb
LF = Pb-free
OAR1 Omit for standard
4/5 characters
OAR3 TP = Tight Pitch See Electrical Data
OAR5
R = ohms
5
General Note
TT Electronics reserves the right to make changes in product specification without notice or liability.
All information is subject to TT Electronics’ own data and is considered accurate at time of going to print.
www.ttelectronicsresistors.com
© TT Electronics plc
11.14