Open-Air Resistors Isolate Hotspots from PC Boards
TT electronics IRC expands its OARS-3 Series of open-air current sense resistors. These metal alloy strip resistors feature a flameproof open-air surface mount design, providing optimal thermal temperature cycling and allowing the resistors to operate to power ratings of at least 3 W. Although the part was originally specified for a maximum of 3 W at 70
C, it is capable of handling to 4 W under ambient conditions and without forced air. The construction of the resistor, including the open-air design and flexible leads, isolates the hotspot from the circuit board material, preventing circuit board damage. These resistors are suitable for surge and pulse circuits, AC power applications, current sensing and feedback circuits while presenting a low inductance signature.