Vishay bases high precision flip-chip 0805 resistor on Z1 foil technology

July 26, 2013 // By Paul Buckley
Vishay Precision Group's Vishay Foil Resistors brand (VFR) has released a new ultra-high-precision Z1-Foil flip-chip resistor, the FRFC 0805, with load-life stability of ±0.005% (50 ppm) at 70°C and rated power for 2,000 hours.

The device also has a low typical TCR of ±0.05 ppm/°C from 0°C to +60°C and ±0.2 ppm/°C from -55°C to +125°C (+25°C ref.); power TCR of 5 ppm at rated power; and tight tolerances to ±0.01%.

Based on VFR's next-generation Bulk Metal Z1-Foil technology, the FRFC 0805 (foil resistor flip-chip) exceeds the performance of all previous stability standards for precision resistors with an order of magnitude improvement in high-temperature stability, load-life stability, and moisture resistance. These new benchmark levels of performance provide design engineers with the tools to build circuits not previously achievable while reducing costs and space in the most critical applications by eliminating the need for corrective circuitry and reducing the large land patterns needed for a wrap-around configuration. The device's flip-chip configuration saves up to 35% PCB space compared with a surface-mount chip with wraparound terminations while also providing strain relief to eliminate cracked substrates and board delamination.

In addition to its improved load-life stability, the FRFC 0805 is noise-free and provides ESD protection of 25 kV or more for increased reliability. The device's solid element alloy is matched to the substrate, forming a single entity with balanced resistance versus temperature characteristics for an unusually low and predictable TCR over a wide temperature range from -55°C to more than +125°C. The adhesive that holds the foil to the flat substrate withstands high temperatures, pulsing power, moisture incursions, shock and vibration, and low-temperature exposure while still holding securely to the foil element. Resistance patterns are photo-etched into the element to permit the trimming of resistance values to very tight tolerances as low as 0.01%.

The FRFC devices are qualified as anti-sulphurated resistors for use in environments with high levels of contamination. Such environments include alternative energy applications, industrial control systems, sensors, RTDs, electric instrumentation, weather and communication base stations, and any electronic appliance used in high concentrations of sulphur.

The FRFC 0805 offers a wide resistance range