13 Conclusions

The struggle and challenge of designing an all-in-one solution that is compact and complies with rigorous EMI standards can be a great hurdle for systems engineers. When designing a switching buck regulator to meet industry EMI standards, mindful consideration of devices that use advanced EMI suppression techniques ensures that the overall system is safe, operable and reliable, even in a noisy environment.

Purposeful device selection and understanding the device features and capabilities also helps ensure that the design complies with industry EMI standards without much design hassle or extensive redesign. An AEF enables the reduction of input EMI filter cost and size. DRSS with ripple cancellation provides spread spectrum to reduce both low-order harmonics and high-frequency noise while avoiding increased audio noise. True slew-rate control can adjust the high-side gate-drive strength to smooth out the rising switching behavior and avoid boot undervoltage lockout penalties through a single dedicated resistor component. Advanced device packaging reduces the input power-loop parasitic. And finally, devices with integrated capacitors provide filtering directly at the noise source, bypassing the package inductances.