To deal with noise, a snubber circuit can be added afterward; but should it be added in the initial design stage? I'd also like to know reasons why this might or might not be necessary (frequency, voltage?).|FAQ|ROHM Semiconductor

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To deal with noise, a snubber circuit can be added afterward; but should it be added in the initial design stage? I'd also like to know reasons why this might or might not be necessary (frequency, voltage?).
- In a DC/DC circuit, a snubber circuit is related to the rising and falling slew rate, and (depending on conditions) is effective for frequencies ranging from tens to hundreds of MHz. However, when considerable noise improvement is needed, resistance losses become extremely large. If a snubber circuit is added improperly, it may mean an appropriate layout cannot be used, so that noise is worsened as a result.
  In the case of DC/DC converter ICs with internal power transistors, positioning the input capacitor as close as possible to the IC input pin is highly effective. Hence layout is emphasized more than use of a snubber circuit.