User's Manual

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

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• The PCB traces to LE940B6 and the bypass capacitor must be wide enough to ensure that no

significant voltage drops occur when the 2A current peaks are absorbed. This is needed for

the same above-mentioned reasons. Try to keep these traces as short as possible.

• The PCB traces connecting the switching output to the inductor and the switching diode must

be kept as short as possible by placing the inductor and the diode very close to the power

switching IC (only for the switching power supply). This is done to reduce the radiated field

(noise) at the switching frequency (usually 100-500 kHz).

• Use a good common ground plane.

• Place the power supply on the board in a way to guarantee that the high current return paths

in the ground plane do not overlap any noise sensitive circuitry, such as the microphone

amplifier/buffer or earphone amplifier.

• The power supply input cables must be kept separate from noise sensitive lines, such as

microphone/earphone cables.