ZHCSN38D October 2021 – April 2024 LMR54406 , LMR54410
PRODUCTION DATA
Radiated EMI is generated by the high di/dt components in pulsing currents in switching converters. The larger area covered by the path of a pulsing current, the more EMI is generated. High frequency ceramic bypass capacitors at the input side provide primary path for the high di/dt components of the pulsing current. Placing a ceramic bypass capacitor or capacitors as close as possible to the VIN and GND pins is the key to EMI reduction.
The SW pin connecting to the inductor must be as short as possible, and just wide enough to carry the load current without excessive heating. Short, thick traces or copper pours (shapes) must be used for high current conduction path to minimize parasitic resistance. The output capacitors must be placed close to the VOUT end of the inductor and closely grounded to GND pin.