Vishay has announced lab-grade resistors aimed at metrology.
Z203 devices feature a temperature coefficient of +/-0.5ppm/°Cmax from +25 to +125°C; tolerances to 50ppm; load-life stability of 50ppm at +70°C for 10,000 hours; and a self-heated resistance change of +/-5ppm at a rated power of 0.6W at +70°C as well as 0.3W at 125°C.
"The resistors offer an immediate answer to many resistor applications currently believed unsolvable, including secondary standards, feedback devices for operational amplifiers, precision voltage dividers, meter multipliers, precision bridge resistors, and decade voltage dividers," claimed the firm.
Within the device, the resistive pattern is photo etched into what is claimed to be a new generation of the firm's Bulk Metal Z-Foil element, on a special ceramic substrate.
Drift is cut by post manufacturing operations (PMO)
"The foil resistor load-life curve shows an increase in resistance from the first load application, but flattens out to no further change after the first few hundred hours of loading," said Vishay. "This knee in the load-life curve is reduced significantly by an accelerated load-life operation, resulting in a flat response immediately after installation. The optional PMO for this product includes the combination of thermal shock, power shot, and burn-in."
Standard and custom values from 10Ω to 100kΩ are available.