MALVERN, Pa.--(BUSINESS WIRE)--
Vishay Precision Group, Inc. (NYSE: VPG) today announced that its Vishay
Foil Resistors brand (VFR) has released new ultra-high-precision Z-Foil
power current sensing resistors for applications where rapid ΔR
stabilization and resistance stability under transient power conditions
are required. Designed to provide optimal performance when mounted on a
chassis or cooled heat sink, the VCS331Z, VCS332Z, VFP4Z, and CSNG
Series feature low TCR of ±0.2 ppm/°C from -55°C to +125°C, +25°C ref.,
PCR (ΔR due to self-heating) of 4 ppm/W typical, and tolerances to
±0.01%. For high-power applications, the devices offer power ratings up
to 10 W (on heatsink) and a four-terminal Kelvin configuration in order
to remove the unwanted influence of lead resistance and lead sensitivity
to temperature.
The VCS331Z, VCS332Z, VFP4Z, and CSNG offer excellent load-life
stability to ±0.005% typical (50 ppm) at 3 W (heat sink) and +25°C for
2,000 hours, a thermal stabilization time of <1 s (within 10 ppm of
steady state value), and a wide resistance range from 0.25 Ω to 500 Ω.
(Lower and higher values are also available.) Any resistance value
within this range is available at any tolerance with no additional cost
or lead time effect. The resistors offer a rise time of 1.0 ns with
effectively no ringing, current noise of 0.010 µVrms/V of applied
voltage (<-40 dB), and a voltage coefficient of <0.1 ppm/V. The devices
withstand ESD to at least 25 kV for increased reliability, and they
offer a non-inductive (<0.08 μH), non-capacitive design.
“In applications such as force-balance scales, electronic beam
deflection systems, and switching power supplies, accuracy and
repeatability are likely to be more important than power handling
requirements and depend to a major extent on precision current sense
resistors with Kelvin connections,” said Yuval Hernik, Senior Director
of Application Engineering for VFR. “The resistors must have extreme
thermal efficiency, well-distributed internal heat from power
dissipation, very low thermal EMF, and fast thermal stabilization. All
these characteristics, which can be found in the VCS331Z, VCS332Z,
VFP4Z, and CSNG, are necessary to prevent errors caused by uneven heat
from external sources such as the power amplifiers and other circuit
elements.”
Many instrumentation circuits depend upon current sense resistors for
precision measurements and system controls. The new devices can also be
used in lithium-ion battery circuits for alternative energy applications
where energy that cannot be harvested must be stored. In
state-of-the-art battery management circuits, Bulk Metal®
Foil resistors can be used in the measurement of the “state-of-charge”
(SOC) of the battery cells. The characteristics of Li-ion cells
complicate SOC measurement, so precise ICs and precision current sense
resistors with improved stability and low thermal EMF help to extend
battery lifetime.
The Bulk Metal Foil resistor is based on the planar construction of a
cold-rolled Ni-Cr foil bonded to a flat ceramic substrate. The
monolithic foil, as opposed to the agglomeration of particles in thin
film resistors, has a strength and substance independent of the
substrate, which gives the metal foil its own specific thermal linear
coefficient of expansion (LCE). The foil also has a known and repeatable
independent positive temperature coefficient of resistance (TCR). When
the foil is bonded to the substrate, it attempts to respond to
temperature changes in accordance with its own LCE but is constrained to
follow the lower LCE of the ceramic substrate. The resistance change due
to the differential LCEs counterbalances the metal’s positive TCR for a
near-zero net TCR of the resistor. The composite formation with a planar
foil structure makes it possible to very accurately etch a pattern into
the resistor that is non-inductive and non-capacitive, with low noise
and low thermal EMF.
The VCS331Z, VCS332Z, and VFP4Z are differentiated by power rating,
thermal EMF, and configuration. The CSNG is a custom version of these
resistors that can be uniquely designed and tailor-made to the
customer’s specific applications and which has already been used by
several research institutes and test and measurement companies.
Samples and production quantities of the VCS331Z, VCS332Z, VFP4Z, and
CSNG are available now, with lead times of five working days for samples
and six weeks for larger orders. Pricing for U.S. delivery starts at
$18.76.
Further information about the VCS331Z, VCS332Z, VFP4Z, CSNG, and other
Vishay Foil Resistors products is available at www.vishayfoilresistors.com.
Follow Vishay Foil Resistors at http://twitter.com/foilresistor.
About Vishay Precision Group
Vishay Precision Group (VPG) is an internationally recognized designer,
manufacturer and marketer of: components based on its resistive foil
technology; sensors; and sensor-based systems specializing in the
growing markets of stress, force, weight, pressure, and current
measurements. VPG is a market leader of Foil Technology Products,
providing ongoing technology innovations in precision foil resistors and
foil strain gages, which are the foundation of the Company’s Force
Sensors Products and its Weighing and Control Systems. The product
portfolio consists of a variety of well-established brand names
recognized for precision and quality in the marketplace. To learn more,
visit VPG at www.vishaypg.com.
About VPG Foil Resistors
VPG Foil Resistors, a part of Vishay Precision Group (VPG), produces the
most precise and stable resistors available. Distinguished by the
premier brands Vishay Foil Resistors, Powertron, and Alpha Electronics,
the VPG Foil Resistors portfolio includes discrete resistors and
resistor networks in surface mount and through-hole (fixed-lead)
configurations; customized chip resistor networks; precision trimming
potentiometers; and discrete chips for use in hybrid circuits. These
devices are used in applications requiring a high degree of precision
and stability, such as in medical testing equipment, semiconductor
equipment, precision measuring instruments, aerospace, and military
applications. To learn more, visit www.vishayfoilresistors.com.
Bulk Metal is a registered trademark of Vishay Precision Group, Inc.
Link to product photo: http://www.flickr.com/photos/[email protected]/9045197958/sizes/l/in/photostream/
Link to detailed product information: http://www.vishaypg.com/ppg?63240
Vishay Precision Group
Marti Spalding, +1 919-374-5515
Director,
Global MarCom
[email protected]
Source: Vishay Precision Group, Inc.