Most power modules integrate a high frequency input capacitor and a shielded inductor. It’s important to note that the integrated input capacitor greatly reduces the area of the high di/dt loop. A smaller loop area creates a lower ringing on the switch node; lowering the ringing on the switch node will therefore lower the output noise. Also, since the switch node is inside the package and has been further reduced, the potential parasitic capacitance to the other nodes is limited. Although reduced, there are still some parasitic elements present in the power module.

TI’s Enhanced HotRod™ QFN package technology offers the best in class EMI performance by the removal of the wire bonds, which contribute significantly to the parasitic inductance of the power loop (MOSFETs gate loop), and the optimized pin-out of the device to further reduce the parasitic loop inductance. In summary, Enhanced HotRod QFN technology leverages the noise improvements of a flipped chip on lead-frame (FCOL) package and thermal advantages of the standard QFN package. For a deeper understanding of Enhanced HotRod QFN package technology see Enhanced HotRod QFN Package.