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LM3478: Input resistor proper placement

Part Number: LM3478

Hello team,

The LM3478 datasheet states that "To improve performance, especially with Vin below 8 volts, it is recommended to use a 20 Ohm resistor at the input to provide an RC filter".

That is on paragraph "8.2.1.2.8 Input Capacitor Selection", a bit before figure 31.

I just got unsure if this filter applies:

a) only to the IC's power supply (before VIN PIN #8), while the main supply to the inductor remains fed directly by the input capacitor, or

b) the resistor is in series both before the VIN pin AND the main inductor.

Thanks in advance for the clarification.

Bruno