About the selection of energy storage inductor in DCDC circuit?

西里古1992

About the selection of energy storage inductor in DCDC circuit? [Copy link]

In the DCDC circuit in the figure, the output current is about 250mA. If I choose the inductor value of L2 as shown in MSS1210 in Figure 2, are the parameters appropriate? What is the difference between Isat and Irms? Which parameter can be used to judge whether the selected inductor is appropriate, mainly the current resistance value? If I change the inductor parameters to Figure 3, is the Rated Current the same as Irms or Isat? The DC Resistance of the SCDS127, 1mH is 1820Ω, is it the same parameter as the DCR parameter of 0.96Ohms of MSS1210 in Figure 2? What is the impact of the huge difference between these two models in this regard?

maychang

"The DC resistance of the SCDS127, 1mH is 1820Ω. Is it the same as the DCR parameter of the MSS1210 in Figure 2, 0.96Ohms? What is the impact of the big difference between the two models in this regard?" What is the impact? Just think about whether your output current of 250mA can be achieved. 250mA×1820Ω, the result is 455V. Is it possible?

topwon

1820Ω is probably a typo of 1820mΩ. The saturation current (Isat) is based on the percentage of inductance drop, so there are three different parameters in the figure: drop 10% 20% 30%. The average current (Irms) is based on the degree of temperature rise caused by inductor heating, so there are two different parameters in the figure: rise 20℃ 40℃. The rated current (Irated) is generally a design reference value given by the manufacturer based on the two parameters of saturation current and average current. I think this value is generally more conservative.