Vishay's Improved S-Series High-Precision Bulk Metal Foil Resistors

Vishay has announced the improved S series of high-precision Bulk Metal foil (BMF) resistors, which provide a military-grade typical TCR of ±2ppm/°C from -55°C to +125°C, +25°C ref., tolerance of ±0.005%, and load life stability of ±0.005% for more than 10,000 hours.

The S series comprises 12 model numbers with resistance values from 0.5Ω to 1MΩ, with any resistance value available at any tolerance within the resistance range at no additional cost or lead time effect. The devices are rated for power levels up to 2W at 70°C and can withstand electro-static discharges (ESD) in excess of 25kV. Rise time for the S series devices is a nearly immeasurable 1ns without ringing.

Devices in the S series are built to handle unconventional environmental conditional conditions with minimal drift, making them well suited for military/space applications according to EEE-INST-002 specifications and MIL-PRF 55182. The ultimate resistor component for analog applications, the construction of S series resistors guarantees a high level of reliability, stable operation in harsh conditions, and high resistance to thermal shock, mechanical shock, and vibrations. Each S series resistor undergoes a short time overload test of 6.25 times the rated power during the manufacturing process.

The new devices are resistant to moisture as well, and are designed with a coating and molding compound that provides water proofing, moisture proofing, and mechanical damping, as well as a path for heat dissipation.

The S series allows designers to achieve much better performance by combining a range of high-precision specifications in a single device. In addition to its low TCR, tolerance, and load life stability values, the S series offers a low voltage coefficient of <0.1PPM/V; current noise of <-42dB; and thermal EMF of 0.05μV/°C. S series resistors offer fast thermal stabilization of less than 1 second, and a non-inductive (<0.08μH), non-capacitive design.

Typical applications for the S series devices will include dc-to-dc converters, feedback circuits, and precision amplifiers in test and measurement instrumentation, medical systems, satellites and aerospace systems, commercial and military avionics, weapons systems, audio systems, and high-temperature systems including down-hole drilling.

Vishay Intertechnology