Vishay Precision Group has announced that its VFR (Vishay Foil Resistors) division has introduced a series of bulk metal Z1-foil hybrid surface-mount chip resistors, connected using gold wire bonding. The HTH series is designed for high-temperature applications up to 240°C and are claimed to offer optimised heat dissipation. The resistors offer temperature co-efficient of resistance of ±1ppm/°C from -55 to +125°C and ±2.5ppm/°C from -55 to +220°C, 25°C reference. They feature load-life stability of ±0.05% at 220°C for 2,000hr at working power, long-term stability of ±0.05% at 240°C for 2,000hr with no power, and tight tolerances of ±0.02%. They withstand ESD of 25kV without degradation and are available in 5x5, 15x5, and 15x10 chip sizes, in addition to six case sizes ranging from 0603 to 2512. There are two chip design layouts which provide a resistance range from 10Ω to 125kΩ. The resistors feature a rise time of 1ns, with effectively no ringing, a thermal stabilisation time of less than 1s, current noise of 0.010µVrms/V of applied voltage of less than -40dB, and a voltage co-efficient of less than 0.1ppm/V. They are suitable for geo-thermal measuring equipment, turbine engine control, and environmental test chambers in military, industrial, and down-hole drilling systems.
