VPG releases HTH foil resistors series

The HTH series is designed for high-temperature applications to +240°C and offers improved heat dissipation, providing nearly a 100°C extension in operating temperature range over precision thin film chip resistors. The HTH series is based on VFR's next-generation Z1-Foil technology, which provides an order of magnitude reduction in the Bulk Metal Foil element's sensitivity to temperature changes — both external and internal — while providing long-term stability in high-temperature environments. HTH devices offer TCR of ±1 ppm/°C from -55°C to +125°C and ±2.5 ppm/°C from -55°C to +220°C, +25°C ref.

"In high-temperature applications, the most important factors are the end-of-life tolerance, which is part of the stability, and, to a lesser extent, the initial tolerance," said Yuval Hernik, senior director of application engineering for Vishay Foil Resistors.

The resistors feature exceptional load-life stability to ±0.05% at +220°C for 2,000 hours at working power, long-term stability to ±0.05% at +240°C for 2,000 hours (no power), and tight tolerances to ±0.02%. The devices are capable of withstanding electrostatic discharges at least to 25 kV without degradation. The HTH series is offered in 5x5, 15x5, and 15x10 chip sizes, in addition to six case sizes ranging from 0603 to 2512. The devices feature two different chip design layouts according to their size. The HTH series devices provide a wide resistance range from 10 Ω to 125 kΩ, with any resistance value within this range available at any tolerance with no additional cost or lead time effect. The resistors feature a rise time of 1.0 ns, with effectively no ringing, a thermal stabilization time of <1 s (nominal value achieved within 10 ppm of steady state value), current noise of 0.010 µVrms per volt of applied voltage (<-40 dB), and a voltage coefficient of <0.1 ppm/V. Samples and production quantities of the HTH series are available now, with lead times of five weeks for samples and eight weeks for standard orders.