Resistors boast superior thermal performance

A new series of noninductive power resistors come with power ratings from 20 to 140W in popular transistor-style packages.

Giving power electronics design engineers a comprehensive range of high-wattage surface mount and through-hole resistors designed to provide superior thermal performance in densely populated power supply circuits, TT Electronics BI Technologies SMT Division has released a series of noninductive power resistors with power ratings from 20 to 140W, 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 to +155C.

"Their superior thermal performance and extreme power ratings make the MHP Series resistors ideal for switch-mode power supply circuits, motor control and drive circuits, automotive electronics, industrial power equipment and UPS systems", explained Jim Rieley, Sales Director for the TT Electronics BI Technologies SMT Division.

"In addition, they exhibit excellent high frequency characteristics for use in high frequency industrial RF power sources, RF linear amplifiers, termination resistor of RF circuit etc".

The MHP Series resistors are available in five power ratings and four TO-style package types.

The MHP-20 Series resistors are in three package styles - TO126 (MHP20S), TO220 (MHP20) and the surface mount TO263 (D2Pak) (SMHP) packages - and are rated for 20W power dissipation, with resistance ranges from 0.01 to 220ohm at maximum power (up to 51kohm is available to 10W rated power), with tolerances of +/-5 and +/-1%, and TCRs from 50 to 250ppm/C.

Thermal resistance is 5.9C/W from the resistor's "hot spot" to the package's metal flange.

The MHP-35 Series resistors are in TO-220 packages, and are rated for 35W power dissipation, with resistance ranges from 0.01 to 220ohm at maximum power (up to 51kohm is available to 20W rated power), with tolerances of +/-5 and +/-1% and TCRs from 50 to 250ppm/C.

Thermal resistance is 3.3C/W from "hot spot" to flange, and maximum operating voltage is 500V.

The MHP-50 Series resistors are in TO-220 packages, and are rated for 50W power dissipation, with resistance ranges from 0.01 to 220ohm at maximum power (up to 51kohm is available to 30W rated power), with tolerances of +/-5 and +/-1%, and TCRs from 50 to 250ppm/C.

Thermal resistance is 2.3C/W from "hot spot" to flange, and maximum operating voltage is 500V.

The MHP-100 Series resistors are in TO-247 packages, and are rated for 100W power dissipation, with resistance ranges from 0.01 to 220ohm at maximum power (higher resistance is available at below rated power), with standard tolerances to +/-5 and +/-1%, and TCRs from 50 to 250ppm/C.

Thermal resistance is 1.3C/W from "hot spot" to flange.

The MHP-140 Series resistors are in TO-247 packages, and are rated for 140W power dissipation, with resistance ranges from 0.01 to 200ohm at maximum power (higher resistance is available at below rated power), with tolerances of +/-5 and +/-1%, and TCRs from 50 to 250ppm/C.

Thermal resistance is 0.9C/W from "hot spot" to flange.

BI Technologies will also produce devices outside these specifications to meet customer requirements, with comprehensive application engineering and design support available for customers worldwide.

The MHP Series resistors feature thermally enhanced two-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, ranging to $4.20 for the MHP-140 Series, with lead times from stock to 8 weeks.

Samples are available immediately for engineering evaluation and customer prototypes.

Back to top