Series 73M1A, 73M2A,
73M3x & 73M5
Current Sensing Resistors – Up To 5W Power
FEATURES
Metal Plate Construction – Copper Alloy
Power Rating @ +70°C, Options 1 – 5 Watts
Resistance Range, 0.25 – 120 milliohms
Operating Temperature to +155°C
EIA Standard Package Sizes
Terminal Finish – Tin (e3)
Reflow capable per JEDEC J-STD-020, 260°C maximum
Tape and Reel Packaging
RoHS/Green Compliant [6/6]
APPLICATIONS
Ideal for applications such as current detection and limiting, regulated battery circuits,
motor control, power supply, hard disk drives, inverter/converter, industrial equipment and automotive.
ORDERING INFORMATION
73M
TYPE
1A = 1 Watt Rating
2A = 2 Watt Rating
3A = 3 Watt Rating
3B = 3 Watt Rating
5 = 5 Watt Rating
R
TOLERANCE
F = ±1%
Notes:
1. No dashes or spaces to appear in part number.
2. Example Part Numbers:
73M2AR0015F [1.5m Ohms, ±1%]
73M3AR00025F [0.25m Ohms, ±1%]
73M3BR050F [50m Ohms, ±1%]
73M5R120F [120m Ohms, ±1%]
RESISTOR CODE
4, 5 or 6-Character Resistor Code
"R" indicates decimal point.
Ex.
R100 = 100m Ohms
R0015 = 1.5m Ohms
R00025 = 0.25m Ohms
Not all performance combinations and resistor values may be available.
Contact your local CTS Representative or CTS Customer Service for availability.
STANDARD RESISTOR VALUES
Standard Resistance Values
4, 5, 6-Digit Codes
Resistor
Resistor
Value
Code
0.00025Ω
R00025
0.00050Ω
R0005
0.0010Ω
R001
0.0015Ω
R0015
0.0020Ω
R002
0.0025Ω
R0025
0.0030Ω
R003
0.0040Ω
R004
0.0050Ω
R005
0.0060Ω
R006
0.0070Ω
R007
0.0080Ω
R008
[Based on EIA E-24 Sequence]
Resistor
Value
0.0090Ω
0.0100Ω
0.0110Ω
0.0120Ω
0.0130Ω
0.0150Ω
0.0160Ω
0.0180Ω
0.0200Ω
0.0220Ω
0.0240Ω
0.0270Ω
Resistor
Code
R009
R010
R011
R012
R013
R015
R016
R018
R020
R022
R024
R027
Resistor
Value
0.0300Ω
0.0330Ω
0.0360Ω
0.0390Ω
0.0430Ω
0.0470Ω
0.0500Ω
0.0510Ω
0.0560Ω
0.0620Ω
0.0680Ω
0.0750Ω
Resistor
Code
R030
R033
R036
R039
R043
R047
R050
R051
R056
R062
R068
R075
Resistor
Value
0.0820Ω
0.0910Ω
0.1000Ω
0.1100Ω
0.1200Ω
Resistor
Code
R082
R091
R100
R110
R120
Document No. 008-0542-0
Page 1 - 3
Rev. A
www.ctscorp.com
Series 73M1A, 73M2A, 73M3x & 73M5
Current Sense Resistor – up to 5W Power
ELECTRICAL CHARACTERISTICS
Type
73M1A
73M2A
73M3A
73M3B
73M5
Rated
Wattage
[Watts]
1
2
3
3
5
Resistance
[mΩ]
1 - 50
1 - 75
0.25 - 3
4 - 100
1 - 120
Tolerance
[%]
±1
±1
±1
±1
±1
T.C.R
[ppm/°C]
R
≥
0.010Ω:
R < 0.010Ω:
R < 0.010Ω:
R
≥
0.010Ω:
R
≤
0.001Ω:
R > 0.001Ω:
±50
R < 0.010Ω: ±100
R
≥
0.010Ω: ±50
±50
±100
±100
±50
±200
±100
Rated Ambient
Temperature
+70°C
+70°C
+70°C
+70°C
+70°C
Operating
Temperature
Range
-55°C to +155°C
-55°C to +155°C
-55°C to +155°C
-55°C to +155°C
-55°C to +155°C
DERATING CURVE
Rated wattage is the maximum continuous power applicable at ambient temperature from -55°C to +70°C [73M5: -55°C to +105°C].
For ambient temperature above +70°C [+105°C], power rating is in accordance with Derating Curves below.
73M5 Only
MECHANICAL SPECIFICATION
PACKAGE DRAWING
Dimensions
[mm]
73M1A
73M2A
L
3.2 ±0.3
6.3 ±0.3
W
1.6 ±0.3
3.2 ±0.3
0.6
0.8
0.6
1.3
t
±0.3
±0.3
±0.3
Max.
c
0.5 ±0.3
1.9 ±0.3
1.1 ±0.3
2.2 ±0.3
1.8 ±0.3
1.2 Max.
73M3B
73M5
6.7 ±0.3
11.4 ±0.3
7.2 ±0.3
6.9 ±0.3
1.3 Max.
1.8 Max.
1.6 ±0.3
1.3 ±0.3
1.1 ±0.3
3.2 ±0.3
1.8 ±0.3
Resistance
[mΩ]
---
1.0 - 4.0
4.1 - 75
0.25, 0.50
1.0
1.5
2.0
2.5
3.0
---
1.0 - 5.0
5.1 - 120
RECOMMENDED LAND PATTERN
Type
73M1A
73M2A
Dimensions
[mm]
A
2.1
3.7
B
1.4
2.8
2.0
3.8
3.4
3.2
2.9
2.7
4.8
3.4
C
1.6
1.9
3.5
1.4
2.2
2.6
3.2
3.5
4.0
6.8
Resistance
[mΩ]
---
1.0 - 4.0
4.1 - 75
0.25 - 1.5
2.0
2.5
3.0
---
1.0 - 5.0
5.1 - 120
1.4 Max.
73M3A
6.8 ±0.3
6.5 ±0.3
1.3 Max.
73M3A
73M3B
73M5
7.1
7.8
7.5
NOTES
1. Terminal:
Base Metal - Copper [Cu].
Barrier Plating - Nickel [Ni].
Finish Plating – Matte Tin [Sn].
Document No. 008-0542-0
Page 2 - 3
Rev. A
Series 73M1A, 73M2A, 73M3x & 73M5
Current Sense Resistor – up to 5W Power
PACKAGING INFORMATION
MARKING
Type
73M1A
Rxxx = "R" is the decimal point and 3 digits [E24] are
significant values. See resistor tables for codes.
Rxxx = "R" is the decimal point and 3 digits [E24] are
significant values. See resistor tables for codes.
73M2A
Nominal resistances that includes a decimal point;
marking is denoted by "m" expressing a decimal point
in milliohms and three digits. Ex. 1m50 [1.5m Ohms]
73M3x
Part Marking
73M5
Rxxx = "R" is the decimal point and 3 digits [E24] are
significant values. See resistor tables for codes.
Rxxx = "R" is the decimal point and 3 digits [E24] are
significant values. See resistor tables for codes.
Nominal resistances that includes a decimal point;
marking is denoted by "m" expressing a decimal point
in milliohms and three digits. Ex. 0m25 [0.25m Ohms]
EMBOSSED TAPE
Type
73M1A
73M2A
73M3A
73M3B
73M5
W
8.00 ±0.15
12.00 ±0.15
12.00 ±0.15
12.00 ±0.15
24.00 ±0.30
P1
4.00 ±0.10
4.00 ±0.10
8.00 ±0.10
12.00 ±0.10
12.00 ±0.10
1.75 ±0.10
E
F
3.50 ±0.10
5.50 ±0.10
5.50 ±0.10
5.50 ±0.10
11.50 ±0.10
Do
1.55 ±0.05
1.50 ±0.05
1.55 ±0.05
4.00 ±0.10
2.00 ±0.10
P0
P2
Ao
1.83 ±0.10
3.50 ±0.10
6.75 ±0.10
7.70 ±0.10
7.20 ±0.10
Bo
3.48 ±0.10
6.74 ±0.10
7.15 ±0.10
7.15 ±0.10
11.80 ±0.10
Ko
0.90 ±0.10
1.10 ±0.10
1.70 ±0.10
1.20 ±0.10
1.70 ±0.10
t
0.20 ±0.05
0.20 ±0.05
0.25 ±0.05
0.25 ±0.05
0.30 ±0.10
REEL
[mm]
Type
73M1A
73M2A
73M3A
73M3B
73M5
Quantity
Per Reel
4,000
4,000
1,000
1,000
500
W
12.0 ±0.5
16.2 ±0.5
16.2 ±0.5
16.2 ±0.5
24.4
+2.0
-0.0
178 ±1.0
2.5 ±0.6
13.5 ±0.6
21.9 ±0.6
60.0 ±0.5
M
A
2.0 ±0.5
B
13.2 ±0.5
C
21.7 ±0.5
D
Document No. 008-0542-0
Page 3 - 3
Rev. A