Metal Strip Current Sense

Resistors Surface Mount

ULR Series

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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

02. 12

Welwyn Components

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08.10

Metal Strip Current Sense Resistors Surface Mount

ULR Series

Construction

Blackcoat

Alow TCR resistance alloyplate,withtin plated connection bandsisprotectivelycoatedon the upperand lower

facesand numericallymarkedwiththe resistance value. Thispartissuitablefor wave or IRreflowsoldering.

Greencoat

Alow TCRresistancealloy plateisgrooved to setthe finalresistance, thelower facesare tinplatedfor

connections, anditisprotectivelycoatedonthe upperand lower facesand numericallymarkedwiththe resistance

value. This partisONLY suitable for IR reflow soldering.

Uncoated

Alow TCRresistancealloy plateisgrooved to setthe finalresistanceand thelower face only is protectedwithan

epoxy coating. The lowerfaces aretin plated forconnections. This partis ONLY suitable forIRreflowsoldering.

Marking

Only 2512 size partsare marked.For values whichare integernumbers of milliohms, themarking is 4-character

IEC62code;e.g.“R002”for 2m ,“R010”for 10m .For values includingfractions of amilliohm themarking is 3or

4-charactercodeusing “M” to indicate thedecimal point, e.g. “M75”for 0.75m ,“1M50”for 1.5m .

TerminationDetails:

Material

Matt tin plated finish over abarrier layer

Solderability

95%min coverage (MIL-STD 202F/208H,235ºC 2 secs)

Sn Plated Finish

GreenCoat& Uncoated

Black

Method

ref.

Test

Black &

uncoated

Green

3

High Temp. Exposure * MIL-STD-202 Method 108

1

1

4

Temperature Cycling

JESD22 Method JA-104

0.5

0.5

6

Moisture Resistance MIL-STD-202 Method 106

1

1

7

Biased Humidity MIL-STD-202 Method 103

1

1

8

Operational Life (Cyclic Load) * MIL-STD-202 Method 108

1

1

14

Vibration MIL-STD-202 Method 204

0.5

0.5

15

Resistance to Soldering Heat * MIL-STD-202 Method 210

0.5

1

16

Thermal Shock * MIL-STD-202 Method 107

0.5

1

18

Solderability

J-STD-002

>95% coverage

21

Board Flex

AEC-Q200-005

0.5

0.5

22

Terminal Strength

AEC-Q200-006

0.25

0.25

Short Term Overload *

5 x Pr for 5s

0.5

1

Notes: 1. Full AEC-Q200 qualification applies to 2512 size. The 1206 and 2010 sizes have received the tests marked *.

Power de-rating graph 100

%

P

50

%

0

%

T°C

80

170

0

-55

Ni Plating