D2pak Heatsink

The D2PAK heatsink (or TO-263 surface mount heatsink) represents a critical innovation in power electronics cooling, enabling high-density PCB designs by bridging the gap between low-power SMD components and traditional through-hole cooling methods. StOhmiteDigikey

Product Overview & Technical Insights

D2PAK heatsinks are primarily made from extruded aluminum to maximize thermal mass and fin geometry compared to stamped metal alternatives. Ohmite

• Mounting Strategy: Unlike traditional heatsinks, these are soldered directly to the PCB copper drain pad rather than the package itself. This eliminates the need for Thermal Interface Materials (TIMs), which often act as a thermal bottleneck. Digikey
• Thermal Performance: They significantly lower the junction-to-ambient thermal resistance ($R_{\theta JA}$) by expanding the dissipation area of the PCB's copper plane. StDigikey
• Assembly Efficiency: Modern designs are compatible with automated SMT pick-and-place and reflow soldering, allowing them to be treated as standard components during assembly. OhmiteDigikey

Market Trends & Sourcing

The market is shifting toward "All-SMT" boards to reduce manual labor and through-hole assembly costs. OhmiteDigikey

• Increased Power Density: As MOSFETs and regulators shrink, the focus is on vertical cooling (fins) to save horizontal board space. Ohmite
• Sourcing Options: Prices for standard units typically range from $0.20 to $1.50 depending on volume and complexity, with major manufacturers like Ohmite, Aavid (Boyd), and specialized OEM suppliers in China offering standardized and custom solutions.