Datasheet

Sales and Corporate Ofce
1717 Chicago Avenue
Riverside, California 92507-2364
Phone: [phone]
Fax: [phone]
Applications Engineering
17271 North Umpqua Hwy.
Roseburg, Oregon 97470-9422
Phone: [phone]
Fax: [phone]
© 2003-2007 Caddock Electronics, Inc.
CAD KDOC
e-mail: [e-mail] • web: www.caddock.com
For Caddock Distributors listed by country see caddock.com/contact/dist.html
ELECTRONICS, INC.
28_IL126.0507
Type SR Precision Current Sense Resistors
Non-inductive Design - Compact Footprint Minimizes Circuit Board Space
Kelvin Terminals (Four Wire) - Resistance Values 0.005Ω to 1.00Ω
Type SR Current Sense Resistors utilize Caddock's Micronox® resistance
lms to achieve a low cost resistor with Non-inductive Performance. This
compact construction makes this sense resistor ideal for many current
monitoring or control applications.
The special performance features of these Type SR Current Sense
Resistors include:
• Available in Standard Resistances down to 5 milliohm.
• Non-Inductive Design.
• Terminals are constructed for Kelvin connections to the circuit board.
• Compact footprint.
0.008 Ω
0.010 Ω
0.012 Ω
0.015 Ω
0.005 Ω
0.008 Ω
0.010 Ω
0.015 Ω
0.020 Ω
0.025 Ω
0.030 Ω
0.033 Ω
0.020 Ω
0.025 Ω
0.030 Ω
0.033 Ω
0.040 Ω
0.050 Ω
0.075 Ω
0.10 Ω
0.040 Ω
0.050 Ω
0.075 Ω
0.10 Ω
Custom resistance values can be manufactured for
high quantity applications. Please contact Caddock
Applications Engineering.
Specications:
Resistance Tolerance: ±1.0%
Temperature Coefficient: TC referenced to
+25°C, ∆R taken at -15°C and +105°C.
0.081 to 1.00 ohm -50 to +100 ppm/°C
0.025 to 0.080 ohm 0 to +150 ppm/°C
0.008 to 0.024 ohm 0 to +200 ppm/°C
0.005 to 0.007 ohm 0 to +300 ppm/°C
Load Life: 1000 hours at rated power at +70°C,
∆R ±(0.2 percent + 0.00001 ohm) max.
Thermal Shock: Mil-Std-202, Method 107, Cond. A,
∆R ±(0.2 percent + 0.00001 ohm) max.
Moisture Resistance: Mil-Std-202, Method 106,
∆R ±(0.2 percent + 0.00001 ohm) max.
Encapsulation: Polymer over resistance element.
Ordering Information:
DIMENSIONS IN INCHES AND (MILLIMETERS)
Measurement note: For purposes of these specications, resistance measurement shall
be made using Kelvin connections (four wire) with appropriate current and sense con-
nections to the device terminals.
C = Current connection S = Sense connection
Circuit Board Layout: The circuit board traces connecting to the current terminals must
be sized appropriately for the current owing through the trace. For example; 0.005Ω
operated at 2.0 Watts would have 20 amps owing through the circuit board traces into
the current terminals.
SR10 - 0.050 - 1%
Model Number:
Resistor Value:
Tolerance
Scale:
actual size
Front view
Side view
Back view
SR10 PACKAGE DIMENSIONS
CIRCUIT BOARD LAYOUT NOTES
0.15 Ω
0.20 Ω
0.25 Ω
0.30 Ω
0.15 Ω
0.20 Ω
0.25 Ω
0.30 Ω
.365 ±.020
(9.27 ±.51)
.370 ±.015
(9.40 ±.38)
.125 ±.020
(3.18 ±.51)
.045 (1.14)
.025 (.64)
.090 (2.29)
MAX.
.032 ±.007
(.81 ±.18)
SR10
0.025Ω
1%
Voltage Rating
Terminal Material
1.0 Watt Power Limited
Solderable
Model No.
SR10
Power Rating at
70°C
*
2.0 Watts Power Limited
Solderable
SR20
Resistance
Min. Max.
0.008 Ω 1.00 Ω
0.005 Ω 1.00 Ω
*
Power rating:
T h e p o w e r r a t i n g
should be limited as
shown by the derating
curve based upon the
m a x i m u m a m b i e n t
temperature. The derating curve is based on still
air with natural convection around the resistor.
Power Derating Curve:
25 150
0
20
40
100
RATED LOAD, %
80
60
70
TEMPERATURE, °C
100
.032 ±.007
(.81 ±.18)
.400 ±.015
(10.16 ±.38)
SR20
0.050Ω
1%
.090 MAX.
(2.29 MAX.)
.565 ±.020
(14.35 ±.51)
.125 ±.020
(3.18 ±.51)
.045 (1.14)
.025 (.64)
.200 (5.08)
Section BB
.045 (1.14)
.100 (2.54)
.200 (5.08)
.045 (1.14)
.025 (.64)
.025 (.64)
B
B
C
S
S
C
.100 (2.54)
Section AA
.045 (1.14)
.100 (2.54)
.100 (2.54)
.045 (1.14)
.025 (.64)
.025 (.64)
A
A
C
S
S
C
SR10
SR20
SR20 PACKAGE DIMENSIONS
0.40 Ω
0.50 Ω
0.75 Ω
1.00 Ω
0.40 Ω
0.50 Ω
0.75 Ω
1.00 Ω
SR10 Standard Resistance Values:
SR20 Standard Resistance Values: