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I built a buck converter using the LM2576HVT-15/NOPB. I built it exactly like the recommended schematic:

enter image description here

The diode I am using is a 1N5822 and the inductor is a 470uH inductor with a 100uF electrolytic capacitor and a 1000uF electrolytic capacitor. I created this circuit on a breadboard. When I use a load that pulls about .75A - 1A, the buck converter seems to work great. But when I use it to power 3 IR2110PBF IC's (which is what my design needs it for) it has a lot of ringing on the output pin before it reaches the inductor as seen in the image below:

enter image description here

While there is a lot of ringing on the output pin, after it goes through the inductor and is smoothed by the 1000 uF capacitor the voltage is pretty constant at 15V with about a 0.5V ripple which is what I want to happen, so perhaps this isn't a problem I need to worry about?

I am curious why is it ringing so much on the output? Is it the layout of my design because it is on a breadboard? Do I need to select a lower value inductor? Why is there no ringing when the load pulls 0.75A - 1A?

Trev347
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    No harm done : ) it is just the buck converter transitioning into the discontinuous conduction mode or DCM. In continuous conduction mode (CCM), the inductor current never cancels within a switching period. When the load current gets lighter, the *average* inductor reduces and, at some point, the *valley* current (the minimum inductor current) hits zero and the diode spontaneously blocks. The switch/diode junction parasitic capacitance forms a resonant network with the inductor and a decaying oscillation takes place until the power switch is turned back on. – Verbal Kint Aug 03 '23 at 15:16

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