TT electronics BI Technologies SMT Division has released a series of noninductive power resistors with power ratings from 20 W to 140 W, in popular transistor-style packages (TO-126, TO-220, TO263 and TO-247). Designated as the MHP and SMHP Series, the resistors are designed to provide complete thermal flow from the resistive element to the integral metal flange of the TO-style packages, giving design engineers the ability to specify them for high-wattage power electronics circuits that can experience elevated temperatures during operation. The devices are all rated for operation from -55°C to +155°C.
The MHP-20 Series resistors are available in three package styles—TO126 (MHP20S), TO220 (MHP20) and the surface-mount TO263 (D2Pak) (SMHP) packages. They are rated for 20-W power dissipation, with resistance ranges from 0.01 Ω to 220 Ω at maximum power (up to 51 KΩ is available to 10-W rated power). Thermal resistance is 5.9°C/W from the resistor’s “hot spot” to the package’s metal flange.
The MHP-35 Series resistors come in TO-220 packages and are rated for 35-W power dissipation, with resistance ranges from 0.01 Ω to 220 Ω at maximum power (up to 51 KΩ is available to 20-W rated power). Thermal resistance is 3.3°C/W from “hot spot” to flange, and maximum operating voltage is 500 V.
The MHP-50 Series resistors come in TO-220 packages and are rated for 50-W power dissipation, with resistance ranges from 0.01 Ω to 220 Ω at maximum power (up to 51 KΩ is available to 30-W rated power). Thermal resistance is 2.3°C/W from “hot spot” to flange, and maximum operating voltage is 500 V.
The MHP-100 Series resistors are available in TO-247 packages and are rated for 100-W power dissipation, with resistance ranges from 0.01 Ω to 220 Ω at maximum power (higher resistance is available at below rated power). Thermal resistance is 1.3°C/W from “hot spot” to flange.
The MHP-140 Series resistors are available in TO-247 packages and are rated for 140-W power dissipation, with resistance ranges from 0.01 Ω to 200 Ω at maximum power (higher resistance is available at below rated power). Thermal resistance is 0.9°C/W from “hot spot” to flange.
All products have tolerances of ±5% and ±1%, and TCRs from 50 ppm/°C to 250 ppm/°C. BI Technologies also will produce devices outside listed specifications to meet customer requirements. The MHP Series resistors feature thermally enhanced 2-leaded industry-standard packages designed for mounting directly to a heatsink. All MHP Series devices are RoHS-compliant and compatible with high-temperature soldering processes normally employed for lead-free solders. Typical low-volume pricing starts at $1.25 for the MHP-20S Series to $4.20 for the MHP-140 Series.
