Why does TPS92691 recommend adding resistors and capacitors to the Vin design?

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Why does TPS92691 recommend adding resistors and capacitors to the Vin design? [Copy link]

The input is 24V DC, but I set the input to 23~25V for safety. The LED I drive is a COB LED. Typical current is 0.17A, power 6.1W. My question now is that in the recommended design of WEBENCH, the official connects a 10Ω, 1/4W resistor Rvin between the input voltage and Vin, and then connects a 0.1uF capacitor Cvin between Vin and GND. I want to know why? I guess it is for soft start or simple filtering. But if filtering is just an inductor, wouldn't it be enough to add a resistor? Please explain it to me. Thank you! Expert reply: TI highly recommends to bypass the VIN pin with a 0.1-μF ceramic capacitor placed as close as possible to the device and add a series 10-Ω resistor to create a 150-kHz low-pass filter and eliminate undesired high-frequency noise. I check the datasheet and find the same answer. For a MCU, we normally add a 0.1uf capacitor to Vcc. But we rarely use low-pass filter. It refreshes my idea. Answer: This is RC filtering to eliminate noise, and VIN is used to power the internal circuit. The inductor is involved in power conversion, not filtering. Yes. I know that inductors are needed for circuit conversion. But you have already answered my question. This Rvin and Cvin provide low-pass filtering for Vin (internal circuit power supply). More answers》》》》》》