SNVSBJ0A December 2019 – June 2020 LM5170
The inductor current has a triangle waveform, as shown in Figure 51. TI recommends selecting an inductor such that its peak-to-peak ripple current is less than 80% of the channel inductor full load DC current. Therefore, the inductor should satisfy Equation 43:
Select Lm = 4.7 µH.
Then, the actual inductor peak to peak inductor current is determined by Equation 44:
The peak inductor current is determined by Equation 45:
Select an inductor that has a saturation current Isat at least 20% greater than Ipeak to ensure full power with adequate margin. In this example, TI recommends selecting an inductor of Isat > 49 A.
The power inductor’s full load Root Mean Square (RMS) current ILM_RMS determines its conduction losses. The RMS current is given by Equation 46: