MALVERN, PA, Sep. 11, 2009 (Marketwire) --
MALVERN, PA -- (Marketwire) -- 09/11/09 -- Vishay Intertechnology, Inc. (NYSE: VSH) today announced the VHP100, a new hermetically sealed ultra-high-precision Bulk Metal® Foil resistor with such a low temperature coefficient of resistance (TCR) that a new definition, "window," has been introduced by Vishay. The window definition requires that the absolute resistance remain within the stated window over the temperature range specified.
The resistance of the VHP100 resistor stays within a 60-ppm window (0.3 ppm/deg. C maximum) over the entire military temperature range of - 55 to + 125 deg. C. This means that the difference between a resistor's maximum resistance value and its minimum resistance value shall not deviate by more than 60 ppm total over the entire military temperature range. This also means that all VHP100 resistors ever built will automatically maintain maximum temperature-related ratios of 120 ppm (0.012 %) over the entire temperature range regardless of whether the resistors are all at different temperatures and whether the different temperatures are caused by environmental temperature variations, locally different heat generated by adjacent power components, or even self-heating in power dissipation. A window of 10 ppm is available for the laboratory instrument range of + 15 to + 45 deg. C.
In addition to its low TCR, the VHP100 provides tight tolerances to +/- 0.005 % (50 ppm) and a load-life stability of +/- 0.005 % (50 ppm) typical for 2,000 hours at + 70 deg. C and 0.3 W. An even tighter tolerance to +/- 0.001 % (10 ppm) is available on request.
Representing a metrology and secondary standard resistor breakthrough, the new VHP100 features a unique construction that minimizes the effects of stress factors, making it an excellent choice for the most demanding instrumentation and laboratory applications.
The ability of the VHP100 to minimize changes in resistance when the resistor is subjected to stress factors ensures ultra-high performance for tight metrology specifications. As applications requiring this level of performance also require immunity to humidity, the device features a hermetically sealed metal and glass enclosure to protect the resistive element, and is oil filled to improve the thermal dissipation path to the outside.
The resistor offers a broad resistance range of 100 ohms to 150 kilohms and a shelf-life stability of +/- 2 ppm typical through at least 6 years, which is essentially the metallurgical stability of the alloy itself. Vishay Foil resistors are not restricted to standard values, and can be supplied with "as required" values (e.g. 1.2345 kilohms vs.
