A Subsidiary of
TT electronics plc
General Note
IRC reserves the right to make changes in product specifi cation without notice or liability.
All information is subject to IRC’s own data and is considered accurate at time of going to print.
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
Metal Element
Current Sense Resistor
ULR Issue December 2009 Sheet 1 of 6
IRC Type Coating1Power rating
at 80°C (Watts)
Standard Resistance
Values (m)2
TCR
(±ppm/°C)
Tolerance
(±%)
Dielectric
Withstanding Voltage
(Volts)
1206 Chip Size
ULRG1 Green 1 1 - 10 50
1, 5 100
ULRB1 Black 1 5, 10 100
20, 25 75
2010 Chip Size
ULRG15 Green 1.5 1 - 10 50 1, 5 100
2512 Chip Size
ULRG1
Green
1 11 - 15 50
1, 5 200
ULRG2 2 7 - 10 50
ULRG25 2.5 4 - 6 50
ULRG3 3 0.5 - 0.75 100
1 - 3 50
ULRB1
Black
111, 12, 15, 18, 20, 25, 30,
33, 40, 50 75
ULRB2 2 1, 1.5, 2, 3, 4, 5, 6, 7, 8,
9, 10
100
Test
Short Term Overload (5x rated power for 5 seconds) ∆R/R ≤ ± 0.5% + 0.5 mΩ (black); ∆R/R ≤ ± 1% (green)
Load at rated power (1000 hours cyclic load @ 70°C)∆R/R ≤ ± 1% + 0.5 mΩ (black); ∆R/R ≤ ± 1% (green)
Temperatature Cycling (-55°C to +150°C; 1000 cycles) ∆R/R ≤ ± 0.5% + 0.5 mΩ (black); ∆R/R ≤ ± 1% (green)
Dry Heat (+170°C, no load; 1000 hours) ∆R/R ≤ ± 0.5% + 0.5 mΩ (black); ∆R/R ≤ ± 1% (green)
Resistance to Solder Heat (260°C for 10 seconds) ∆R/R ≤ ± 0.5% + 0.5 mΩ (black); ∆R/R ≤ ± 1% (green)
Solderability (235°C for 2 seconds) Minimum 95% coverage
Resistance to Solvents No deterioration of protective coating or marking
Operating Temperature -55°C to 170°C
ULR Series
Robust metal strip able to withstand high temperature and high current.•
Low TCR and Inductance•
Resistance Range from 0.5 mΩ to 50 mΩ•
Power ratings from 1W to 3W in 1206, 2010 and 2512 chip size•
Designed for current sense circuits in power electronic systems•
Higher wattage devices feature PCB clearance gap to maximize thermal •
performance
Electrical Data
Notes:
1.Black coating = wave or IR refl ow soldering; Green coating = IR refl ow solder. Wave refl ow - solder mask must match the W and D dimensions on page 2
of data sheet. 2Non-listed resistance values available (contact factory). For non-listed resistance values above 20 mΩ, please refer to our LRC / LRF series.
3 Package sizes 2010 and 1206 with the green coating are uncoated on the top surface and unmarked for resistance value.
Environmental Data
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 ULR Issue December 2009 Sheet 2 of 6
D
W
T
L
Coating Resistance
Value (m)
LWT D
1206 Chip Size (1 Watt)
Green 1 - 10 3.2 ± 0.25 1.6 ± 0.10 0.6 ± 0.2 0.98 ± 0.38
Black 5 - 20 3.2 ± 0.2 1.6 ± 0.2 0.6 ± 0.2 0.5 ± 0.3
2010 Chip Size (1.5 Watt)
Green 1 - 10 5.08 ± 0.25 2.54 ± 0.15 0.6 ± 0.2 1.67 ± 0.63
2512 Chip Size (1 Watt, 2 Watt, 2.5 Watt, and 3 Watt)
Green
0.5
6.35 ± 0.25 3.18 ± 0.35 0.6 ± 0.2
2.68 ± 0.25
0.75 2.48 ± 0.25
1 - 1.5 1.43 ± 0.25
2 - 3 1.18 ± 0.25
4 2.18 ± 0.25
5 - 6 1.93 ± 0.25
7 1.43 ± 0.25
8 - 20 1.18 ± 0.25
Black
≤ 2 6.4 ± 0.2 3.2 ± 0.2 0.6 ± 0.2 2 ± 0.2
> 2 - 50 0.9 ± 0.2
Physical Data
Note:
1 Dimensions are for reference only
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 ULR Issue December 2009 Sheet 3 of 6
a
1.0
L
1.2
4-wire pad layout
Lb
2-wire pad layout
1.5
5.4
4-wire measurement points
unit: mm unit: mm unit: mm
0.5
Probe dia.
2512 2512 2512
a
0.5
0.7
unit: mm unit: mm unit: mm
Lb1.25
2.6
0.5
Probe dia.
4-wire pad layout 2-wire pad layout 4-wire measurement points1206 1206 1206
L
aa
Package
Resistance
(m-ohm) a b L
2512 - Black
≤ 2 3.1 4.0 1.3
> 2 - 50 2.1 4.0 4.1
2512 - Green
0.5 2.78
3.45
0.9
0.75 2.58 1.3
1 - 1.5 1.53 3.4
2 - 3 1.28 3.9
4 2.28 1.9
5 - 6 2.03 2.4
7 1.53 3.4
8 - 20 1.28 3.9
Package
Resistance
(m-ohm) a b L
2010 - Green
1 2.04
2.9
1.2
2 1.74 1.8
3 1.24 2.8
4 - 5 2.04 1.2
6 - 8 1.74 1.8
9 - 10 1.49 2.3
1206 - Black 5 - 20 1.9 1.8 1.4
1206 - Green
1 1.3
1.9
0.8
2 - 3 0.8 1.8
4 - 6 1.3 0.8
7 - 9 1.1 1.2
10 0.8 1.8
Electrical Connections
Note:
1 Green parts require the use of “D” dimensions on page 2 for parts being assembled in a wave refl ow processes.
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 ULR Issue December 2009 Sheet 4 of 6
Ambient Temperature (°C)
Rated Power (%)
100
50
70 170
0
0
Power Derating Curve
Note:
The power derating curve is a guidance based on a conservative
design model. The ULR is a solid metal alloy construction that
can withstand signifi cantly greater operating temperatures than
the conservative model permits. The protective coating will
operate up to 260°C and the alloy can withstand in exess of
350°C. Therefore, the system thermal design will be a more
signifi cant design parameter due to the heat limitations of the
solder joint.
Black Type
A low TCR resistive alloy is coated with a molding compound that
permits the part to be used in all refl ow processes by controlling
the solder attachment area. Copper electrode reduces resistance
measurement sensitivity that can result from connection directly
to the resistive alloy. Nickel / Tin plating provides a solder
compliant surface.
Green Type
A low TCR alloy plate is grooved to set the fi nal resistance. The
lower faces are solder plated for connections, and the top surface
is protectively coated and numerically marked with the resistance
value, as described in Product Marking. This part is suitable for
wave and IR refl ow soldering processes. Wave refl ow requires the
solder mask to be dimensioned according to page 2 using the W
and D dimensions of the part.
Construction
Ni / Sn
Plating
Copper
Electrode
UL-94 V0 grade
molding compound
Resistive
Alloy
ULR Black
20 m at 2 Watts
Thermal Images
The above images are based on a standard test circuit board constructed of a four layer FR4 material with 2-ounce outer
layers and 1-ounce inner layers, which is typical of many industry designs. Each of the above images are in ambient
temperature conditions with no air fl ow. Contact IRC for more details or for other thermal image test data for specifi c
resistance values and power levels.
ULR Green
10 m at 2 Watts
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 ULR Issue December 2009 Sheet 5 of 6
Note 1: Package volume excludes external
terminals (balls, bumps, lands, leads) and/or
non-integral heat sinks.
Note 2: The maximum component temperature
reached during refl ow depends on package
thickness and volume. The use of convection
refl ow processess reduces the thermal gradients
between packages. However, thermal gradients
due to differences in thermal mass of SMD pack-
ages may still exist.
Note 3: Components intended for use in “lead-
free” assembly process shall be evaluated using
the “lead-free” peak temperature and profi les
defi ned in Table 1, 2 and refl ow profi le whether
or not lead-free.
Tabel 1: SnPb Eutectic Process -
Package Peak Refl ow Temperatures
Package
Thickness Volume mm3 < 350 Volume mm3 ≥ 350
< 2.5 mm 240 +0/-5°C 225 +0/-5°C
≥ 2.5 mm 225 +0/-5°C 225 +0/-5°C
Tabel 2: Pb-free Process -
Package Peak Refl ow Temperatures
Package
Thickness
Volume mm3
< 350
Volume mm3
350 - 2000
Volume mm3
> 2000
< 1.6 mm 260°C * 260°C * 260°C *
1.6 mm - 2.5 mm 260°C * 250°C * 245°C *
≥ 2.5 mm 250°C * 245°C * 245°C *
* Tolerance: The device manufacturer/supplier shall assure process compat-
ibility up to and including the stated classifi cation temperature at the rated MSL
level.
Note 1: All temperatures refer
to topside of the package,
measured on the package
body surface.
Note 2: Time within 5 °C of
actual peak temperature (tp)
specifi ed for the refl ow profi les
is a “supplier” minimum and a
“user” maximum.
Profi le Feature Sn-Pb Eutectic
Assembly
Pb-Free
Assembly
Average Ramp-up rate (Tsmax to Tp) 3°C / second max. 3°C / second max.
Preheat
- Temperature Min (Tsmin)
- Temperature Max (Tsmax)
- Time (Tsmin to Tsmax) (ts)
100°C
150°C
60 -120 seconds
150°C
200°C
60 -180 seconds
Time maintained above
- Temperature (TL)
- Time (tL)
183°C
60 - 150 seconds
217°C
60 - 150 seconds
Peak Temperature (TP) See Table 1 See Table 2
Time within 5°C of actual Peak Temperature (tp)210 - 30 seconds 20 - 40 seconds
Ramp-down Rate 6°C / second max. 6°C / second max.
Time 25°C to Peak Temperature 6 minutes max. 8 minutes max.
Sn-Pb Eutectic and Pb-Free Reflow Profiles
Time
Temperature
Critical Zone
TL to TP
Ramp-down
Ramp-up
t 25°C to Peak
TP
TL
Tsmax
Tsmin
ts
Preheat
tL
25
tP
* Based on Industry Standards and IPC recommendations
IRC Solder Refl ow Recommendations
W
E
F
ψ D 0
P1P2P0direction of unreeling
A
B
Top Tape
Resistor
Emboss Tape
T
ψ D 1 1.4Min.
Size Resistance
(m)ABWEFP
0P1P2 D0T
ULR Green
2512 0.5 - 7 3.4±0.1 6.73±0.1 12±0.1 1.75±0.1 5.5±0.05 4±0.1 4±0.1 2±0.05 1.5+0.1, -0 0.81±0.1
0.5 - 20 6.75±0.1 1.5+0.1, -0 0.80±0.1
2010 1 - 10 2.85±0.1 5.55±0.1 12±0.1 1.75±0.1 5.5±0.05 4±0.1 4±0.1 2±0.05 1.55±0.05 0.85±0.1
1206 1 - 10 1.9±0.1 3.6±0.1 8±0.2 1.75±0.1 3.5±0.05 4±0.1 4±0.1 2±0.05 1.55±0.05 0.87±0.1
ULR Black
2512 1 - 50 3.6±0.2 6.9±0.2 12±0.2 1.75±0.1 5.5±0.05 4±0.05 4±0.1 2±0.05 1.5+0.1, -0 0.85±0.15
1206 5 - 20 2.0±0.15 3.6±0.2 8.0±0.2 1.75±0.1 3.5±0.05 4±0.1 4±0.1 2±0.05 1.5+0.1, -0 0.84±0.1
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 ULR Issue December 2009 Sheet 6 of 6
Packaging Quantity
Series Footprint Emboss
Plastic Tape
ULR
Green
2512 2,000
2010 2,000
1206 2,000
ULR
Black
2512 4,000
1206 5,000
Product Marking
Part resistance is indicated by using two
marking notation syles:
4-digit: R002 = 2 mΩ; R designates the •
decimal location in ohms.
3-digit: 1M5 = 1.5 mΩ; M designates •
the decimal location in milli-ohm.
Plastic Tape Specifi cation
Note:
The cumulative tolerance of 10 sprocket hole pitch is ± 0.2 mm.1.
Carrier camber shall not be more than 1 mm per 100 mm through a length of 250 mm.2.
A & B measured 0.3 mm from the bottom of the packet.3.
T measured at a point on the inside bottom of the packet to the top surface of the carrier.4.
Pocket position relative to sprocket hole is measured as the true position of the pocket and not the pocket hole.5.
IRC Type
Coating Color Code
G = Green, B = Black
Power Rating
(see specs table)
Package Size
Resistance Value (EIA 4-digit code)
Example: 0.010 = R010
Tolerance (EIA format)
F = 1%, J = 5%
RoHS - Compliance
LF = RoHS compliant Construction
Packaging
SLT = Standard Lead Tape
Reference Identifi er
Only applicable to black ULR
Ordering Data
Specify type, resistance, tolerance, ROHS compliance and packaging.
Example: Metal Element Current Sense Resistor, 1-watt, 10 mΩ resistor.
ULR 1 2512 R010 F LF SLT
Sample Part No. GA
