A Subsidiary of

TT electronics plc

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.

Telephone: 361 992 7900 • Facsimile: 361 992 3377 • Website: www.irctt.com

Metal Element

Current Sense Resistor

ULR Issue July 2009 Sheet 1 of 6

IRC Type

Power rating

at 80°C (Watts)

Standard Resistance

TCR

(±ppm/°C)

Tolerance

(±%)

Dielectric

Withstanding Voltage

(Volts)

1206 Chip Size

ULRG1

Green

1

1, 2, 3, 5, 7, 10

50

1, 5

100

2010 Chip Size

ULRG15

Green

1.5

1, 2, 3, 5, 7, 10

50

1, 5

100

2512 Chip Size

ULRG1

Green

1

11 - 20

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

1

2.5 - 3

150

4 - 5

100

6 - 7

75

ULRB2

2

0.5 - 2

50

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 ≤ ± 1% + 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 20 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 reflow soldering; Green coating = IR reflow solder. Wave reflow - solder mask must match the W and D dimensions on page 2

of data sheet. 2Non-standard resistance values available (contact factory). For 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