How to control the minimum loop area of a PAC (Power Controller for Intelligent Control)?

Controlling the signal loop area on the PCB of the intelligent controller is key to reducing radiation and inductive reactance. For critical signals (such as clock and high-speed data lines), use a routing method where the outgoing and returning signals are adjacent, preferably using differential pairs or microstrip/stripline structures to minimize the loop area. For power circuits, place decoupling capacitors (such as 0.1μF) close to the power and ground pins, ensuring the loop area formed by the capacitor and pin is less than 1mm². For high-current paths (such as power input), use Kelvin connections or large-area copper plating.

During layout, place related components as close as possible to shorten trace lengths. Use simulation tools (such as ANSYS SIwave) to calculate loop inductance, aiming to reduce the high-frequency (>100MHz) loop inductance to below 10nH. Experimental results show that reducing the loop area by 50% can reduce radiated emissions by 6dB, signal ringing by 30%, and pass the IEC61000-4-3 radiated emissions test.