VCS1610Z (Kelvin Connection)
Vishay Foil Resistors
High Precision Foil Surface Mount Current Sensing Chip
Resistors with TCR of 0.2 ppm/C, Load Life Stability of 0.015 %,
ESD Immunity up to 25 kV and Fast Thermal Stabilization
FEATURES
Temperature coefficient of resistance (TCR):
0.2 ppm/C typical (- 55 C to + 125 C,
+ 25 C ref.) (see table 1)
Resistance range: 0.3 to 10
Resistance tolerance: to 0.5 %
Load life stability:
0.015 % at 70 C, 2000 h at rated power
INTRODUCTION
Power rating: 0.25 W at + 70 C
The Z-foil technology provides a significant reduction of the
Vishay Foil resistors are not restricted to standard values;
resistive components sensitivity to ambient temperature
specific as required values can be supplied at no extra
variations (TCR) and applied power changes (PCR).
cost or delivery (e.g. 0.345 vs. 0.3 )
Designers can now guarantee a high degree of stability and
Electrostatic discharge (ESD) at least to 25 kV
accuracy in fixed-resistor applications using solutions based
Thermal stabilization time < 1 s (nominal value
on Vishays Foil Resistors revolutionary Z-foil technology.
achieved within 10 ppm of steady state value)
Model VCS1610Z is a surface mount chip resistor designed
Short time overload < 0.005 %
with 4 pads for Kelvin connection. Utilizing Vishays Bulk
Non-inductive, non-capacitive design
Metal Z-foil as the resistance element, it provides
Thermal EMF: 0.05 V/C typical
performance capabilities far greater than other resistor
technologies can supply in a product of comparable size. Current noise: 0.010 V /V of applied voltage
RMS
0.2 ppm/C typical TCR (- 55 C to + 125 C,+ 25 C ref.) (< - 40 dB)
removes errors due to temperature gradients.
Rise time: 1 ns effectively no ringing
Voltage coefficient: < 0.1 ppm/V
This small device dissipates heat almost entirely through the
pads so surface mount users are encouraged to be generous
Non inductive: < 0.08 H
with the boards pads and traces.
Non hot spot design
Our application engineering department is available to Prototype quantities available in just 5 working days
advise and to make recommendations. For non-standard or sooner. For more information, please contact
technical requirements and special applications, please foil@vishaypg.com
contact us.
(1)
FIGURE 1 - POWER DERATING CURVE
TABLE 1 -TOLERANCE AND TCR VS.
- 55 C + 70 C
RESISTANCE VALUE
100
(- 55 C to + 125 C, + 25 Ref.)
75
TYPICAL TCR
VALUE AND
TOLERANCE 50
( ) MAX. SPREAD
(ppm/C)
25
0R5 to 10R 0.5 %, 1 % 0.2 4.8
0
- 75 - 50 - 25 0 + 25 + 50 + 75 + 100 + 125 + 150 + 175
0R3 to 0R5 0.5 %, 1 % 0.2 9.8
Ambient Temperature (C)
Note
Note
(1)
Power rating: 0.25 W at + 70 C
Tighter tolerances and higher values are available. Please
contact application engineering foil@vishaypg.com
* TERMINATIONS
Tin/lead plated
Two options of lead (Pb)-free leads available:
Gold plated
Tin plated
* Pb containing terminations are not RoHS compliant, exemptions may apply
Document Number: 63226 For any questions, contact: foil@vishaypg.com www.vishayfoilresistors.com
Revision: 6-Jul-12 1
Percent of Rated Power VCS1610Z (Kelvin Connection)
Vishay Foil Resistors
Why use Kelvin connections? Should I be concerned about the impact of ESD on my
resistor?
Four-terminal connections or Kelvin connections are
Electrostatic Discharge (ESD) is known to produce
required in these low ohmic value resistors to measure a
catastrophic failures in thin-film and thick-film (cermet)
precise voltage drop across the resistive element. The
resistors at only 3000 V. On the other hand, the Bulk Metal
4-terminal configuration eliminates the IR-drop error voltage
Foil resistor withstands ESD events up to 25 kV because its
that would be present in the voltage sense leads if a standard
thicker resistance element and greater metallic mass afford
two-terminal resistor were used.
much higher energy-handling capability than either the much
In current sense resistors the contact resistance and the
thinner thin-film resistor or the sparse, non-homogeneous
terminations resistance may be greater than that of the
metallic content of the thick film resistor.
resistive element itself so lead connection errors can be
significant if only two terminal connections are used.
Should I be concerned about stability?
In order to select the resistor technology most appropriate to
Why is the VCS1610Z vital in avoiding Thermal EMF
the application, a designer must take into account all normal
(parasitic effect)?
and extraordinary stresses the resistor will experience in the
When two dissimilar metals are heated, a parasitic voltage is
application. In addition, the designer must consider the cost
generated and creates a DC-offset error. This voltage is
and reliability impact involved when it becomes necessary to
proportional to a temperature difference between either end
add costly additional compensating circuitry when
of the pair of conductors. This phenomenon is called a
inadequate resistors are selected. The stability of Bulk
Thermal Electro-motive Force (Thermal EMF), or
Metal Foil resistors, together with the advantages already
thermocouple effect. Thermal EMF is an important
mentioned, as well as the other basic advantages apparent
consideration in low ohmic current sensing resistors used
in their specifications will not only provide unequalled
mostly in DC circuits. The VCS1610Z is the ideal solution to
performance in the circuit but will eliminate all the costs
minimize the effect of thermal EMF through the use of
associated with extra compensation circuitry.
appropriate materials between the resistive layer and the
With VCS1610Z, only a minimal shift in resistance value will
terminations.
occur during its entire lifetime. Most of this shift takes place
during the first few hundred hours of operation, and virtually
no change is noted thereafter.
FIGURE 2 - TRIMMING TO VALUES(Conceptual Illustration)*
Current Path
Before Trimming
Current Path
After Trimming
Trimming Process
Removes this Material
from Shorting Strip Area
Changing Current Path
and Increasing
Resistance
NOTE: Foil shown in black, etched spaces in white
* To acquire a precision resistance value, the Bulk Metal Foil chip is
trimmed by selectively removing built-in shorting bars. To increase the
resistance in known increments, marked areas are cut, producing
progressively smaller increases in resistance. This method eliminates
the effect of hot spot and assures the long term stability of the Foil
chips.
www.vishayfoilresistors.com For any questions, contact: foil@vishaypg.com Document Number: 63226
2 Revision: 6-Jul-12