Resistors
Surface
Mount Sense Resistors
Make Possible
Surface Mount Sense Resistors
OARS, OARS-XP, OARSZ Series
Surface
Sense Resistors
OARS,
OARS-XP,Mount
OARSZ Series
Flexible leads for thermal expansion
Open-air
design
reduces
heating
Flexible
leads for
thermalPCB
expansion
Values
downdesign
to 1mΩ
Open-air
reduces PCB heating
Element TCR ±20ppm/ºC
OValues
down
to 1milliohm
ARS,65A
OARS-XP,
OARSZ Series
Zero-ohm
jumper version
Element
TCR
±20ppm/°C
RoHS compliant
Flexible leads for thermal expansion
Zero-ohm
jumper
versionPCB heating
Open-air65A
design
reduces
Values
down
to
1mΩ
RoHS compliant
Element TCR ±20ppm/ºC
ElectricalZero-ohm
Data
65A jumper version
RoHS compliant
Power rating at 25ºC
Electrical
Data
Power rating
at 85ºC
Electrical Data
Resistance range
Resistance Tolerance
Power rating
Standard
Values
Power
rating at
at 70°C
ambient,
or 25ºC
140°C
(Enquire for
unlisted
values)
terminal
temperature
Power
rating
at 85ºC
All parts are Pb-free and comply with EU
Directive 2011/65/EU (RoHS2)
OARS1/3
OARS-XP
watts
watts
ohms
%
2
4
1
2
R002 to R050
R001 to R025
OARS1
OARS3
OARS-XP
≤ R002: 5, > R002: 1, 5
OARS1/3
OARS-XP
watts
2 25, 30, 40, 503
2 20, 22,
milliohmswatts
2, 3, 4, 5, 10, 15,
watts
nHohms
ohms
°C %
%
Inductance
Resistance range
Resistance
range
Resistance
Tolerance
AmbientResistance
temperature
range
Tolerance
Standard Values
Standard
Values
milliohms
milliohms
(Enquire for
for unlisted
unlisted values)
(Enquire
values)
amps nH
Current Inductance
rating at 25ºC
temperature range amps °C
Ambient
Current rating at 85ºC
Ambient temperature range
°C
4 10,
5 20, 25
1, 2, 2.5, 5, 7.5,
1
2
<10
R002 to R002
R050 to R050
R002
to R015
to R025
R001R001
to R025
≤≤ R002:
5,
>
R002:
1,
5
-55
to
+160
R002: 5, > R002: 1, 5
2, 3, 4, 5, 10, 15, 20,
1, 2, 2.5, 5, 7.5,
2, 3,40,
4, 50
5, 10, 151, 2, 2.5, 5, 7.5, 10, 20, 25
2, 22,
3, 4,25,
5, 30,
10, 40,
15, 50
20, 22, 25, 30,
12.5, 10, 20, 25
OARS-1Z
Comments
<10
<10
65
-55
-55 to
to +160
+160
Zero-ohm jumper
46
-55 to +160
amps
milliohms
amps
°C
Dimensions (mm) and recommended solder°Cpads
OARS-1Z
OARS-1Z
Current rating
Current
rating at
at25°C
25ºCambient
Physical
Data
Max
residual
resistance
Current rating at 85ºC
Ambient temperature
Ambient
temperature range
range
Type
Physical Data
L
H
T
3.05
OARS1/3
> R003, OARS-1Z
Temperature
Derating
±
0.76
Dimensions
(mm)
and recommended
solder
pads
11.18
Type
OARS1/3 - R003
±0.38
L
H
D
T
W
4.83
±0.76D
3.51 3.05 2.36
OARS1/3 > R003, OARS-1Z
11.5611.18 ±0.76±0.76 ±0.25
4.74.83
OARS1/3 - R002
±0.38
±0.76
±0.76
±
0.38
OARS1/3 - R003
3.51
2.36
10.7 to
2.28 to
4.83
OARS-XP
±0.25
11.564.57*±0.76
4.7
±0.76
12.0*
OARS1/3 - R002
* Dependent on ohmic value
OARS-XP
* Dependent on ohmic value
±0.38
10.7 to
12.0*
Comments
Comments
65 65
46 0.3
to +160
-55 to-55
+160
±0.76
2.28 to
4.57*
Zero-ohm
jumper
Zero-ohm
jumper
a nom. b nom. c nom. d nom.
3.18
4.07
±0.38
W
a nom. b nom. c nom. d nom.
3.18
3.56
4.07
4.45
6.35
7.24
±0.38
±0.38
3.56
±0.38
4.45
±0.38
4.83
6.35
±0.76
7.24
±0.38
OARS1/3/XP
c
a
3.07
9.37
3.07
9.58
3.18
9.58
3.18
b
d
c
OARSZ
9.37
b
d
3.23
3.23
c
c
a
Note: For OARS1/3/XP this relates to power rating, for OARSZ it relates to current rating.
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.
© TT Electronics plc
www.ttelectronicsresistors.com
07.11
07.11
11.15
Surface Mount
Sense
Resistors
Surface
Mount Sense Resistors
Make Possible
OARS, OARS-XP, OARSZ Series
OARS, OARS-XP, OARSZ Series
Performance
Electrical
Data
Data (AEC-Q200)
OARS1
OARS3
OARS-XP
OARS1/3
<R004
R004 to R015
watts
2
3
5
at 70°C ambient, or 140°C
OARS-XP
<R002
R002 to R007
terminal temperature
Resistance
range to 125ºC)
ohms
R002 toppm/ºC
R050
R002 to240
R015
R001 to R025 40
TCR (-55
Resistance
Tolerance
%
R002: 1, 5
Thermal
Shock
∆R% ≤ R002: 5, >0.75
0.75
2, 3, 4, 5, 10, 15, 20,
1, 2, 2.5, 5, 7.5,
Standard Values
milliohms
2, 3, 4, 5,1.75
10, 15
High
Temp.
Exposure
(125ºC)22, 25, 30, 40,
∆R%
(Enquire
for unlisted
values)
50
12.5, 10, 20, 25 0.5
Inductance
nH
<10 1
Temp. Cycling (-40 to 125ºC)
∆R%
1
Ambient
temperatureLife
range
°C
-55 to +160
Operational
∆R%
2
1
Biased Humidity
∆R%
0.75
0.5
OARS-1Z
Comments
Current
rating at 25°C Shock
ambient
amps
Mechanical
∆R% 65
1.5
1
Max residual resistance
milliohms
Zero-ohm jumper
Vibration
∆R% 0.3
1
1
Ambient temperature range
°C
-55 to +160
Terminal Strength
Meets JIS-C-6429
Solvent Resistance
Meets MIL-STD-002 Method 215
Solderability
Meets J-STD-002 Method B
Temperature Derating
Power rating
Tem perature Derating
Pulse Energy Rating
100
Energy (J)
% of Rated Power
120
80
OARS1/3/XP
60
OARSZ
40
20
120
100
80
60
40
20
0
1
10
Note: For
0 OARS1/3/XP this relates to power rating, for OARSZ it relates to current rating.
0
25
50
75
100
125
150
OARS1/3
Note: For OARS-1Z the above derating graph may be applied to
the square of the current rating.
Joint Temperature Rise
Hot Spot Temperature Rise
7.6mm x 7.6mm pads, 2 oz copper on FR4, still air
50 / 25
30 / 15
150
10 / 5
100
5/-
50
50%
75%
100%
Temperature Rise (K)
Temperature Rise (K)
Value in m illiohm s
OARS1/3 / OARS-XP
200
0
25%
OARS-XP
Note: This graph relates to single pulses of short duration (≤ 100ms).
Higher energy limits apply for longer pulses and overloads
7.6m m x 7.6m m pads, 2 oz copper on FR4, still air
250
100
Value (m illiohm s)
175
Am bient Tem perature (Deg C)
300
>R015
>R007
40
0.75
1
0.75
1
0.5
1
1
100
Value in milliohms
OARS1/3 / OARS-XP
80
5/-
60
10 / 5
30 / 15
40
50 / 25
20
0
25%
Proportion of Rated Power
50%
75%
100%
Proportion of Rated Power
Note: Temperature rise data are given here for typical mounting conditions. Actual figures depend on PCB copper weight, mounting pad size, track
width and substrate type. Also, the open air format responds better to forced air cooling than chip format resistors. For values below 5 milliohms
allowance should be made for heat generated in the copper tracks themselves. Application-specific guidance is available on request.
07.11
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
11.15
Surface Mount
Sense Resistors
Make Possible
OARS, OARS-XP, OARSZ Series
Thermal Performance Examples
OARS1-R005 at 2W
OARSXP-R0025 at 5W
These thermal images were taken under ambient conditions of still air at 25°C with the components
mounted on horizontal standard test boards as defined below.
JEDEC standard circuit board:
2” (50.8mm) square FR4
2 outer power planes, 2 ounce (70μ) Cu
1” (25.4mm) square exposed
2 inner signal planes, 1 ounce (35μ) Cu
(continuous planes)
In contrast to the flat chip format, the OARS format keeps the hot spot thermally distant from the
solder j oints and reduces undesirable heat delivery into the PCB. Further thermal images for other
ohmic values and power dissipations are available on request.
Kelvin (4 Terminal) Mounting
For high precision applications a Kelvin (4
Terminal) mounting method is
recommended. An example to illustrate the
design principle is shown. High current
connections are made to the two pairs of
larger pads, whilst the voltage sense
connections are made to the two smaller
central pads.
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
11.15
Surface Mount
Sense Resistors
Make Possible
OARS, OARS-XP, OARSZ Series
Standard 4-Terminal Probe Positions for Measuring Unmounted Parts
Standard 4-Terminal Probe Positions for Measuring Unmounted Parts
0.79
6.35
0.79
6.35
Ø 0.76
Ø 0.76
1.27
1.27
Surface Mount Sense Resistors
7.94
OARS, OARS-XP, OARSZ Series
All dimensions in mm
All dimensions in mm
7.94
Construction
Copper terminations are welded to resistance alloy strip which is then formed. Value adjustment is achieved
by control of width, without the need for subsequent abrasion or notch trimming.
Pb-free termination finish is 96% Sn / 4% Ag alloy.
Flammability
The resistor will not burn or emit incandescent particles under any condition of applied temperature or overload.
Marking
The parts are legend marked with ohmic value and tolerance code.
Packaging Data
Dimensions (mm)
Type
OARS1/3, OARS-1Z
OARS-XP-R001
OARS-XP >R001
A
4.32±0.08
7.21±0.1
B
11.7±0.08
11.94±0.1
11.56±0.1
C
D
E
24±0.3
11.5±0.1
1.75±0.1
F
8±0.1
12±0.1
G
4±0.1
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
11.15
Surface Mount
Sense Resistors
Make Possible
OARS, OARS-XP, OARSZ Series
Ordering
Procedure
Ordering
Procedure
This product has two valid part numbers:
European (Welwyn) Part Numbers:
O
A
R
S
1
OARS1-R01JI (OARS1, 10 milliohms ±5%, Pb-free)
OARS-1Z (OARS-1Z, Pb-free)
-
R
0
1
2
J
I
3
4
1
2
3
4
Type
Value
Tolerance
Termination & Packing
F = ±1%
J = ±5%
I = Pb-free, Tape & Reel
OARS1, OARS3 1900/reel
OARS-XP
1200/reel
OARS1
3-5 characters
OARS3 See Electrical Data
R = ohms
OARS-XP
O
1
A
R
S
-
1
Z
1
1
Type
OARS-1Z No value or tolerance applies. Termination is Pb-free. Packing is Tape & Reel, 1900/reel.
USA (IRC) Part Numbers:
O
A
R
S
OARS1R010JLF (OARS1, 10 milliohms ±5%, Pb-free)
OARS-1ZLF (OARS-1Z, Pb-free)
1
R
0
1
2
0
J
3
L
F
4
1
2
3
4
Type
Value
Tolerance
Termination & Packing
F = ±1%
J = ±5%
LF = Pb-free
OARS1, OARS3 1900/reel
OARS-XP
1200/reel
OARS1
4/5 characters
OARS3 See Electrical Data
R = ohms
OARS-XP
O
1
A
R
S
1
-
1
Z
L
F
2
1
2
Type
Termination & Packing
OARS-1Z
No value or tolerance applies. LF= Pb-free, Tape & Reel, 1900/reel.
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
11.15