SLYT816 October   2021 TPS548B27 , TPS548B28

 

  1. Introduction
  2. Design considerations
  3. Layout comparison
  4. Thermal comparison
  5. Efficiency comparison
  6. Load transient comparison
  7. Switch-node ringing comparison
  8. Conclusion
  9. Additional Resources
  10. 10Important Notice

Thermal comparison

Each circuit board was operated at a 15-A current and measured the IC temperature of each design while operating under the same conditions. The IC temperature of the Enhanced HotRod QFN package was 70.3°C, shown in Figure 4-1. The HotRod package was also 70.3°C, shown in Figure 4-2. No other notable differences were observed. It is safe to conclude that any temperature variation between the two package examples would likely be caused by the IC’s lot-to-lot process variations, such as the drain-to-source on-resistance (RDS(on)) or the switching frequency. The Enhanced HotRod QFN package offered no improvement or degradation of thermal performance compared to the HotRod package.

GUID-20210908-SS0I-ST7Q-4KQ9-T7SFCLV5RB4W-low.jpg Figure 4-1 Enhanced HotRod QFN package thermal image
GUID-20210908-SS0I-M0L2-WWDG-BKQSHFBQN26M-low.jpg Figure 4-2 HotRod package thermal image