TT Electronics OARS Open Air Sense Resistors
TT Electronics OARS Open Air Sense Resistors are precision surface mount current sense resistors available as one-watt or three-watt. The OARS series resistors feature a resistive element with a unique open-air “flow-through” design that keeps the resistor’s “hot spot” safely off the PC board and allows air to circulate it, contributing to cooler operations through increased heat dissipation. The unique lead form of the OARS resistors provides an inherent advantage in compliance with the mechanical stress caused by thermal cycling. The welded copper terminals in the OARS series also offer a low-resistance terminal to enhance reliable performance for demanding applications.
Features
- 65A zero-ohm jumper version
- AEC-Q200 qualified for reliability
- Leads designed for thermal expansion flexibility
- Open-air design to minimize PCB heating
- Values as low as 1mΩ
Applications
- AC applications
- Current sensing
- Electric power steering
- Feedback
- Low Inductance
- Surge and pulse
- Seat belt pre-tensioner
- Window lift applications
Technical Specifications
| Parameters | Values |
|---|---|
| Power rating | 2W, 3W, and 5W |
| Resistance tolerance | 1% and 5% |
| Resistance range | 1Ω to 50Ω |
| Inductance | <10nH |
| Ambient temperature range | -50°C to +160°C |
Video
This TTI Tech Specs video for TT Electronics OARS Current Sense Resistors explains that the OARS series features a unique design that keeps the resistor’s hot spot safely off the board and allows air to circulate around it to keep it cooler.
See Video Transcript Below
Video Transcript
I had a current sense resistor in my last design that was getting particularly hot. Great for making breakfast in the lab, but not great for reliability, so we switched it out for an OARS Current Sense Resistor from TT Electronics. The OARS series features a unique design that keeps the resistor’s hot spot safely off the board and allows air to circulate around it to keep it cooler. The resistors have low-resistance copper terminals and a unique flexible lead design that tolerates the high thermal cycle counts required in automotive applications.
The OARS series is available with 2W, 3W, and 5-W ratings, with resistance values from 1mΩ to 50mΩ with less than 10nH of inductance. A 65A zero-ohm jumper is also available. TT Electronics OARS series current sense resistors are flameproof and can be used in ambient temperatures from -55°C to +160°C.
