Space systems designers often struggle with how to reliably attach surface mount hermetic power packages to PCBs, due to material differences and coefficient of thermal expansion mismatch. The challenges lie in two main areas:

• Maintaining reliable solder joints between the PCB and power packages
• Preserving the sealed integrity of highly reliable, hermetically packaged devices

IR HiRel, an Infineon Technologies company, solves this issue with its QPL-qualified radiation-hardened (rad hard) MOSFETs housed in an innovative direct-to-PCB mounting, the SupIR-SMD.

SupIR-SMD, optimized for surface mount attach

Previously, designers may have resorted to using a ‘dead bug’ and lead configuration, with the power packages turned upside down and attached to the PCB using leads. Not only does this configuration dissipate heat sub-optimally, but it decreases MOSFET capacity.

In contrast, the SupIR-SMD is capable of attaching directly to the PCB and proven to meet the most stringent reliability testing in this configuration, as detailed in IR HiRel’s Application Note 1222. Compared to the typical packaging solutions used in space applications, the SupIR-SMD delivers a more direct thermal path for heat transfer, along with:

• 37% smaller footprint
• 34% lighter mass
• 33% higher current density

System designers can now optimize power system efficiency through direct attach of the SupIR-SMD package to the PCB, enabling the shortest thermal conduction path without compromise to system reliability.

The new SupIR-SMD QPL-qualified rad hard MOSFETs are available immediately, with the MIL-PRF-19500 package identifier ‘U2A.’

More product details are available in the table below.

SupIR-SMD Series Specifications

Related Resources

• PCB board-level testing for space discretes
• Space power management solutions