Foil resistors debut with flexible terminations

Vishay Precision Group Inc. announced that its Vishay Foil Resistors division (VFR) has released a new series of ultra-high-precision Bulk Metal Foil chip resistors offering flexible terminations, low TCR of ±2.0 ppm/°C typical from -55°C to +125°C, +25°C ref., and load-life stability to ±0.01% at +70°C for 2,000 hours at rated power.

Offered in 1206, 2010, and 2512 chip sizes, the VSMF series features a wide resistance range from 10 Ω to 125 kΩ, with tolerances to ±0.01%. Any resistance value within this range is available at any tolerance with no additional cost or lead-time effect. The devices provide a power rating to 400 mW at +70°C and withstand electrostatic discharge (ESD) to at least 25 kV. 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), a voltage coefficient of <0.1 ppm/V, and a thermal EMF of 0.05 μV/°C. The RoHS-compliant devices offer a non-inductive (<0.08 μH), non-capacitive design. 

Typical chips in sizes of 1206 and larger occasionally fall off the printed circuit board (PCB) or develop substrate cracks, mainly due to bending during assembly and other stresses introduced through handling of the PCB, excess thermal gradients, or thermal shock. Thermal stresses can occur due to changes in ambient temperature or internal heat generation in the resistor itself. Whatever the cause, stress cycling due to thermal phenomena can cause material fatigue and cracks.

The VSMF series eliminates the problems of cracked substrates and board delamination by providing flexible terminations for strain relief, thereby increasing reliability.

Key highlights:

• Temperature coefficient of resistance (TCR): ±2.0 ppm/°C typical (–55°C to +125°C, +25°C ref.)
• Resistance range: 10 Ω to 125 kΩ
• Resistance tolerance: to ±0.01%
• Power rating: to 400 mW at +70°C
• Load life stability: to ±0.01% at 70°C, 2000 h at rated power
• Strain relief construction by flexible terminations
• Vishay Foil resistors are not restricted to standard values
• Thermal stabilization time < 1 s (nominal value achieved within 10 ppm of steady state value)
• Electrostatic discharge (ESD): at least to 25 kV
• Thermal EMF: 0.05 μV/°C
• Non inductive, non capacitive design
• Rise time: 1 ns effectively no ringing
• Current noise: 0.010 μVRMS/V of applied voltage
• (<–40 dB)
• Voltage coefficient <0.1 ppm/V
• Non inductive: <0.08 μH
• Non hot spot design

Pricing: For U.S. delivery starts at $4.28.

Availability: Samples and production quantities are available now, with lead times of five days for samples and eight weeks for standard orders.

Datasheet: Click here.