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FAN5631/FAN5632 Rev. 1.0.2

applications where conductive and radiated EMI/RFI interfer-

ence has to be kept as low as possible, consider the use of

additional input and output filtering.

PCB Layout Considerations

While evaluating the FAN5631/FAN5632 (or any other switched

capacitor DC-DC converter) the user should be careful to keep

the power supply source impedance low; use of long wires

causing high lead inductances and resistive losses should be

avoided. A carefully laid out ground plane is essential because

current spikes are generated as the bucket capacitor is charged

and discharged. The input and output bypass capacitors should

be placed as close to the device pins as possible.