MALVERN, PENNSYLVANIA July 28, 2010 Vishay Precision Group, Inc. (NYSE: VPG) today announced that its Vishay Foil Resistors H and HZ series of Bulk Metal® Foil resistors have been selected for Electronic Design’s "Top 101 Components." The annual list compiles the 101 most popular components from the previous year among readers of the magazine’s Products of the Week newsletter.
products offer an immediate answer to many challenging resistor applications previously thought to be unsolvable, including resistance standards, feedback devices for operational amplifiers, precision voltage dividers, meter multipliers, precision bridge resistors, and decade voltage dividers. As a result, the devices open entirely new areas of design where the use of resistors had not been considered.
In both “H” family product series, the resistive element is mounted on a PCB board to which axial leads are anchored. The electrical connection between the resistive element and the leads is provided through a special low-stress construction. After the assembly is inserted into a tinned brass shell, moisture is removed from inside the package using a proprietary process, and the unit is oil-filled and solder-sealed to permit uniform heat dissipation and minimize the effects of extreme environments. The hermetic sealing eliminates the ingress of moisture and oxygen, while the oil acts as a thermal conductor.
By combining these techniques with its Bulk Metal Foil technology, Vishay Foil Resistors has created in its “H” family products the most precise and stable resistors available.
and HZ series
(Z-Foil) feature tolerances of 0.001 % (10 ppm), a resistance range of 5Ω to 1.84 MΩ, shelf-life stability of 2 ppm (± 0.0002 %) for at least six years (unaffected by humidity), a thermal stabilization time of < 1 s (nominal value achieved
within 10 ppm of steady state value) and a rise time of < 1 ns, effectively no ringing. Maximum TCR ranges from ± 2 ppm/°C for the H series to ± 0.2 ppm/°C for the Z-Foil HZ series. (MIL temperature range). The TCR is smaller for lower temperature range.
With their extremely tight specifications, these devices are virtually secondary standards that can be carried in sets for daily or periodic calibration of factory measurement equipment. A ruggedized version using a special rubber filling to replace the oil is suitable for on-board reference standards in highly sophisticated equipment such as aeronautical and deep-space applications. “H” family devices are also available with laboratory- and metrology-level precision and long-term stability with additional in-house oriented processes such as chip stabilization, special TCR plotting, additional treatments for ultra-stability, and special post manufacturing operations (PMO), such as temperature cycling, short-time overload, and accelerated load life, which are uniquely applicable to Bulk Metal Foil resistors.
About Vishay Foil Resistors
Vishay Foil Resistors is a division of Vishay Precision Group, producing the most precise and stable type of resistors available. Our portfolio comprises products in a variety of resistor configurations and package types to meet the needs of a wide range of applications: discrete resistors and resistor networks in surface mount and through-hole (leaded) configurations; customized chip resistor networks; precision trimming potentiometers; and discrete chips for use in hybrid circuits. Our foil resistors and current sensors are used in applications requiring a high degree of precision and stability, such as in medical testing equipment, high performance audio equipment, precision measuring instruments and aerospace and military applications.
About Vishay Precision Group
Vishay Precision Group produces sensors based on precision resistive foil technology, and sensor-based systems. We provide vertically integrated products and solutions for multiple growing markets in the areas of stress, force, weight, pressure and current measurements. As a spin-off from Vishay Intertechnology, our decades-long track record encompasses innovations in foil precision resistors which we invented, current sensors, and strain gages, which have served as a foundation for our more recent expansion into strain gage instrumentation, load cells and transducers, weighing modules and complete systems for process control and on-board weighing.