Vishay WSR Series, Power Metal Strip®, SMD

WSR series of Power Metal Strip® resistors offers power ratings of 2, 3 & 5 Watts in a molded 4527 package size. The WSR2 (2 W), WSR3 (3 W) and WSR5 (5 W) measure 0.455 in. by 0.275 in. [11.56 mm by 6.98 mm] with a height profile of 0.095 in. [2.41 mm]. The WSR resistor’s proprietary construction features a molded, high-temperature encapsulation for improved thermal management. As a result, the device maintains the superior electrical characteristics of the Power Metal Strip construction during operation in a variety of high-current applications. Low thermal EMF, a broad operating temperature range of –65°C to +275°C, and resistance to moisture, vibration, thermal and mechanical shock ensure reliable operation. The WSR’s proprietary Power Metal Strip design features all-welded construction, solderable terminations, and a solid metal alloy resistive element. The WSR’s high power capability in a compact package enables designers to shift away from leaded resistors to a surface mount solution, and thus to create smaller, lower cost, and/or higher performing end products. When used to replace through hole current-sensing resistors, the WSR reduces manufacturing placement costs while allowing for total solder reflow assembly. Per device costs also are further reduced by the elimination of secondary operations such as lead forming and trimming.

Features

  • Compact 4527 package size
  • Low resistance values: from 1 mΩ to 1.0 Ω in a standard resistance tolerance of ±1%. (A tolerance of ±0.5% is available for the resistance range of 10 mΩ to 1.0 Ω with a temperature coefficients of ±75 ppm/°C)
  • Inductance values as low as 0.5 ŋH up to 5 ŋH
  • Resistant to thermal and mechanical shock, extreme temperatures, humidity, and vibration
  • Operating temperature range: - 65 ºC to + 275 ºC
  • Lead (Pb)-free version is RoHS-compliant

Applications

  • Telecommunications - Power Supplies for base stations
  • Computer /Servers – DC/DC Converters and VRMs
  • Automotive – electronic controls

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