TT electronics BI Technologies SMT Division has developed two series of non-inductive planar power resistors with power ratings from 3 W to 50 W at 70°C. Designated as the BPC and BPR Series, the resistors are vertically oriented through-hole planar power devices with thick-film resistive elements on ceramic substrates that are designed to dissipate power above the circuit board. Their vertical orientation gives design engineers more flexibility in pc-board design and eliminates the need for high temperature soldering to PCB.
“The robust construction and power ratings of these resistors give them superior surge power characteristics for inrush current limiting applications, snubber circuits, power supply preloads and UPS systems,” explained Jim Rieley, sales director for the TT electronics BI Technologies SMT Division. “The BPC Series can handle up to 20X rated current and the BPR Series can handle up to 15X rated current for up to 8 ms, with no significant change (±0.5%) in R values.”
The BPC Series resistors are available in 3-W, 5-W, 7-W and 10-W power ratings (@70°C), with resistance ranges from 0.1 Ω to 200 kΩ, and standard tolerances of ±1%, ±2%, ±5% and ±10%. TCRs are 100 ppm/°C, and operating temperature range is from -55°C to +125°C. Maximum operating voltage is 300 Vac/500 Vdc.
The BPR Series resistors are available in 3-W, 5-W, 7.5-W, 10-W, 20-W, 30-W, 40-W and 50-W power ratings (@70°C), with resistance ranges from 0.1 Ω to 200 kΩ, and standard tolerances of ±1%, ±2% and ±5%. TCRs are 100ppm/°C, and operating temperature range is from -55°C to +125°C. Maximum operating voltage is 500 Vdc, with a dielectric strength of 750 V. Contact BI Technologies for power resistor networks with multiple resistors.
The BPC Series resistors have standard copper alloy through-hole leads, while the BPR Series devices feature heavy-duty phosphor-bronze double leads that make them ideal for withstanding shock- and/or vibration-prone environments. Both series are RoHS compliant.
Typical low volume pricing starts at $0.31 for the BPC Series and $1.03 for the BPR Series. Samples are available for customer prototypes.