csm2512s-html.html

IMPROVED PRODUCT

Bulk Metal

Technology High Precision, Current Sensing, Power Surface

Mount, Metal Strip Resistor with Improved Stability 0.05 %, Resistance

Value from 10 m

, Rated Power to 1 W and TCR to 0 ± 15 ppm/°C

CSM2512S

Vishay Foil Resistors

Document Number: 63145

For any questions, contact:

foil@vishaypg.com

www.vishayfoilresistors.com

Revision: 3-May-11

The CSM’s series of low value current sense resistors
provides power and precision in a four terminal, surface
mount configuration. Its all welded construction is made
up of a Bulk Metal

resistive element with plated copper

terminations.

Vishay Foil Resistors’ application engineering department is
available to advise and make recommendations.

For non-standard technical requirements and special
applications, please contact

foil@vishaypg.com

FEATURES

•

Temperature coefficient of resistance (TCR):
(- 55 °C to + 125 °C, + 25 °C ref.)
± 15 ppm/°C maximum
± 10 ppm/°C maximum on special request

•

Load life stability to ± 0.05 % (70 °C, 2000 h
at rated power)

•

Power rating: 1 W

•

Resistance tolerance: ± 0.1 %

•

Resistance range: 10 m

to 100 m

•

Vishay Foil resistors are not restricted to standard values,
we can supply specific “as required” values at no extra cost
or delivery (e.g. 10.2345 m

vs. 10 m

)

•

Short time overload: ± 0.1 % typical

•

Thermal EMF: < 3 µV/°C

•

Maximum current: up to 10 A

•

Surface mount configuration

•

Four terminal (Kelvin) design: allows for precision accurate
measurements

•

Terminal finishes available: lead (Pb)-free, tin/lead alloy

•

Screening in accordance with EEE-INST002 available
(Per MIL-PRF-55342 and MIL-PRF-49465; see
datasheets of 303144 and 303145 )

•

Prototype quantities available in just 5 working days or
sooner. For more information, please contact

foil@vishaypg.com

•

For better performances please contact Application
Engineering

* Pb containing terminations are RoHS compliant, exemptions may apply

∞

FIGURE 1 - POWER DERATING CURVE

- 65 - 50

- 25

100

125

150

170

Ambient Temperature (°C)

100

Rated Power (%)

+ 70 °C

TABLE 1 - PERFORMANCE SPECIFICATIONS

PARAMETER

CSM2512S

Resistance Range

10 m

to 100 m

Power Rating at 70 °C

1 W

Maximum Current

10 A

Maximum Working Voltage

(P x R)

1/2

Tightest Tolerance

± 0.1 %

Temperature Coefficient Maximum (- 55 °C to + 125 °C, + 25 °C ref.)

± 15 ppm/°C, ± 10 ppm/°C is available

Operating Temperature Range

- 65 °C to + 170 °C

Weight (maximum)

0.09 g

CSM2512S

Vishay Foil Resistors

www.vishayfoilresistors.com

For any questions, contact:

foil@vishaypg.com

Document Number: 63145

Revision: 3-May-11

IMPROVED PRODUCT

ABOUT CSM

(Low Ohm Value 10 m

to 100 m

)

The CSM2512S series of low value current sense resistors
provides power and precision in a four terminal, surface
mount configuration. Its all welded construction is made up
of a Bulk Metal

resistive element with plated copper

terminations. For low value resistors in precision applications
it is necessary to use four-terminal Kelvin connections to
obtain a precise voltage drop across the resistive element.

In these applications, the contact resistance and the terminal
resistance may have the same order of magnitude or be
even greater than that of the element resistance itself. Thus,
significant error is introduced because the high temperature
coefficient of resistance of the leads and the contact
resistance are unavoidably incorporated into the
measurements when the current sense resistor has only two
leads.

Because the ability to measure low values to tolerances of
0.1% or tighter is a concern to both the manufacturer and the
user, many situations require coordination of measurement
standards between both parties. Coordination is often
accomplished by exchange of serialized units with recorded
readings to align measurement practices and specific
reference standards. The problem is compounded when
high-precision current sensors under moderate to high
power experience self-heating (Joule effect) which causes
the in-service resistance value to be different from that
obtained using low current measurement equipment.
Therefore, the measurement conditions must be defined and
accepted at the time of spec preparation-that is, resistance
value as determined by specified current and measured
IR-drop following a specified period of stabilization.

Measurement equipment is available from a number of
sources with varying stated accuracies. Traditional passive
current sensors and shunts generate heat under power,
which changes their resistance, and thus their voltage
output. The CSM’s low absolute TCR reduces errors due to
temperature gradients, thus reducing a major source of
uncertainty in current measurement. The CSM can withstand
unconventional environmental conditions, including the
extremely high temperatures and radiation-rich
environments of down-hole oil exploration and well logging,
or the deep-sea underwater repeaters in cross-ocean
communications. The stability of the CSM can be further
enhanced by post-manufacturing operations (PMO), such as
temperature cycling, short-time overload, and accelerated
load life which are uniquely applicable to Bulk Metal

Foil

resistors. The device features a low thermal electromotive
force (EMF) that is critical in many precision applications.
Thermal EMF in DC applications induces a voltage offset in
the resistor that is equivalent to adding a small battery into
the circuit.

The CSM’s all-welded construction is a Bulk Metal

resistive

element with welded copper terminations, plated for
soldering. The terminations make a true continuous contact
with the resistive layer along the entire side of the resistive

element, thereby minimizing temperature variations. Also,
the resistor element is designed to uniformly dissipate power
without creating hot spots, and the welded terminations
material is compatible with the element material. These
design factors result in a very low thermal-EMF(<3 µV/°C)
resistor, because in addition to the low thermal EMF
compatibility of the metals, the uniformity and thermal
efficiency of the design minimizes the temperature
differential across the resistor, thereby assuring low thermal
EMF generation at the leads. This further reduces the
“battery effect” exhibited by most current-sensing or
voltage-reference resistors. Thus, the parasitic voltage
generated at the junction of two dissimilar metals, which is
especially important in low-value current-sensing resistors, is
minimized, while the pure current-to-voltage conversion is
protected from such interference in DC applications.

The stability problems associated with analog circuits are
very pervasive, but knowledgeable selection of a few
high-quality resistors, networks, or trimming potentiometers
in critical locations can greatly improve circuit performance,
long-term application-related performance, as well as the
designer’s peace-of-mind. Additionally, the overall system
cost is often reduced when a knowledgeable designer
concentrates costs in a few exceptionally stable components
with minimal deviation and whose load and environmental
stability can often eliminate the necessity of additional
compensating circuitry or temperature-controlling systems.
The higher reliability and better overall system performances
also achieve excellent product results in the field, enhancing
market acceptance and product reputation. Designers often
unnecessarily pay for tighter tolerances than required simply
to accommodate the resistance stability shifts they know to
be imminent in an application due to the large
application-related changes in the components they
selected. Selection of a high-stability component like the
CSM in these applications eliminates the need for shift
allowance due to “planned instability” and allows the use of
looser initial tolerances than would otherwise be necessary.

CSM2512S

Vishay Foil Resistors

Document Number: 63145

For any questions, contact:

foil@vishaypg.com

www.vishayfoilresistors.com

Revision: 3-May-11

IMPROVED PRODUCT

Note

(1)

White dots indicate top side of part for mounting purposes

FIGURE 2 - DIMENSIONS AND IMPRINTING

in inches (millimeters)

DIMENSIONS - TOLERANCES ± 0.010 (± 0.254), * ± 0.015 (± 0.381)

RESISTANCE RANGE (

)

0.01 to 0.1

0.250 (6.350)

0.125 (3.175)

0.025 (0.635)

0.030 (0.762)

0.030 (0.762)*

0.032 (0.813)*

LAND PATTERN DIMENSIONS - TOLERANCES ± 0.003 (± 0.076)

RESISTANCE RANGE (

)

0.01 to 0.1

0.160 (4.06)

0.145 (3.68)

0.055 (1.39)

0.065 (1.65)

0.045 (1.14)

0.021 (0.53)

CSM2512S DIMENSIONS

(1)

CSM2512S LAND PATTERN

Kelvin Connection
I

, I

- Current

, E

- Sense

TABLE 2 - CSM2512S PERFORMANCE SPECIFICATIONS

TEST

CONDITIONS

MIL-PRF-49465B

R LIMITS

TYPICAL

LIMITS

MAXIMUM

R LIMITS

Thermal Shock

- 55 °C to + 150 °C, 1000 cycles, 15 min at

each extreme

± (0.5 % + 0.0005R)

0.1 %

0.2 %

Load Life Stability

2000 h, 70 °C at rated power

± (1.0 % + 0.0005R)

0.05 %

0.2 %

Bias Humidity

85 °C, 85 % humidity

10 % bias, 1000 h

± (0.5 % + 0.0005R)

0.05 %

0.2 %

Short Time Overload

5 x rated power for 5 s

± (0.5 % + 0.0005R)

0.1 %

0.2 %

High Temperature Exposure

1000 h, 170 °C

± (1.0 % + 0.0005R)

0.2 %

0.3 %

Low Temperature Storage

MIL-PRF-49465

± (0.5 % + 0.0005R)

0.05 %

0.1 %

Moisture resistance

MIL-STD-202, method 106, 0 % power,

7a and 7b not required

± (0.5 % + 0.0005R)

0.02 %

0.05 %

Shock

100 g, 6 ms

± (0.1 % + 0.0005R)

0.02 %

0.05 %

Vibration

(10 Hz to 2000 Hz) 20 g

± (0.1 % + 0.0005R)

0.02 %

0.05 %

Resistance to Soldering Heat

10 s to 12 s at + 260 °C

± (0.25 % + 0.0005R)

0.05 %

0.1 %

Solderability

MIL-STD-202

95 % coverage

CSM2512S

Vishay Foil Resistors

www.vishayfoilresistors.com

For any questions, contact:

foil@vishaypg.com

Document Number: 63145

Revision: 3-May-11

IMPROVED PRODUCT

Note

(1)

For non-standard requests, please contact application engineering.

FIGURE 3 - LOAD LIFE RESULTS OF CSM2512S VS. CSM2512

-1500

-1000

-500

500

1000

1500

0 500 1000 1500 2000

2500

R/R (ppm)

Time (Hours)

CSM2512S 0R05

Load Life 2000 HRS @ 1 W @ +70°C (15 units)

-3000

-2500

-2000

-1500

-1000

-500

500

1000

1500

2000

2500

3000

0 500 1000 1500 2000

R/R (ppm)

Time (Hours)

CSM2512 0R05

Load Life 2000 HRS @ 1 W @ +70°C (15 units)

TABLE 3 - GLOBAL PART NUMBER INFORMATION

NEW GLOBAL PART NUMBER: Y44870R10000B0R (preferred part number format)

DENOTES PRECISION

VALUE

CHARACTERISTICS

(1)

= standard part, tin/lead termination

= standard part, lead (Pb)-free termination

1 - 999

= custom

PRODUCT CODE

RESISTANCE TOLERANCE

PACKAGING

4487

= CSM2512S

= ± 0.1 %

= ± 0.25 %

= ± 0.5 %

= ± 1.0 %

= waffle pack

= tape and reel

FOR EXAMPLE: ABOVE GLOBAL ORDER Y4487 0R10000 B 0 R:
TYPE: CSM2512S

VALUE: 100.0 m

ABSOLUTE TOLERANCE: ± 0.1 %

TERMINATION: standard tin/lead

PACKAGING: tape and reel

HISTORICAL PART NUMBER: CSM2512S 0R1000 B B T (will continue to be used)

CSM2512S

0R1000

MODEL

OHMIC VALUE

ABS. TOLERANCE

TERMINATION

PACKAGING

0R1000

= 0.100

= ± 0.1 %

= ± 0.25 %

= ± 0.5 %

= ± 1.0 %

= lead (Pb)-free

= tin/lead

= tape and reel

= waffle pack

Vishay Precision Group

Document No.: 63999

Revision: 27-Apr-2011

www.vishaypg.com

Legal Disclaimer Notice

Disclaimer

Legal Disclaimer Notice

Disclaimer

Document No.: 63999

Revision: 27-Apr-2011

ALL PRODUCTS, PRODUCT SPECIFICATIONS AND DATA ARE SUBJECT TO CHANGE WITHOUT NOTICE.

Vishay Precision Group, Inc., its affiliates, agents, and employees, and all persons acting on its or their
behalf (collectively, “Vishay Precision Group”), disclaim any and all liability for any errors, inaccuracies or
incompleteness contained herein or in any other disclosure relating to any product.

The product specifications do not expand or otherwise modify Vishay Precision Group’s terms and
conditions of purchase, including but not limited to, the warranty expressed therein.

Vishay Precision Group makes no warranty, representation or guarantee other than as set forth in the terms
and conditions of purchase.

To the maximum extent permitted by applicable law, Vishay Precision

Group disclaims (i) any and all liability arising out of the application or use of any product, (ii) any and
all liability, including without limitation special, consequential or incidental damages, and (iii) any and
all implied warranties, including warranties of fitness for particular purpose, non-infringement and
merchantability.

Information provided in datasheets and/or specifications may vary from actual results in different
applications and performance may vary over time. Statements regarding the suitability of products for
certain types of applications are based on Vishay Precision Group’s knowledge of typical requirements that
are often placed on Vishay Precision Group products. It is the customer’s responsibility to validate that a
particular product with the properties described in the product specification is suitable for use in a particular
application.

No license, express, implied, or otherwise, to any intellectual property rights is granted by this document, or
by any conduct of Vishay Precision Group.

The products shown herein are not designed for use in life-saving or life-sustaining applications unless
otherwise expressly indicated. Customers using or selling Vishay Precision Group products not expressly
indicated for use in such applications do so entirely at their own risk and agree to fully indemnify Vishay
Precision Group for any damages arising or resulting from such use or sale. Please contact authorized
Vishay Precision Group personnel to obtain written terms and conditions regarding products designed for
such applications.

Product names and markings noted herein may be trademarks of their respective owners.