Lo and behold the Applications example had a similar requirement as do I. on page 15 of the datasheet the current requirement (OUT) is stated Iload1=Iload2=400 mA, Iload3=1a Iload4=1.25A. However in the calculations the ripple current is 40% of Iout or 0.5A for determining the inductor value. which results in higher values of inductors than calculated. When putting in the correct values I get an inductor value of 15uH for both 5V and 3.3V. Is this an error? Isn't a 15uH too large for a 400 mA current.
When putting the actual values Iload at 5V of 0.1A and 3.6V of .3A I get inductor values of 33 and 15 uH. Is this part not good for low currents? I like it because I can tie the phases of the regulators to be anti-phase.The 2.5 and the 1.8V circuits are fine. I'm just concerned about the low current inductors.Could I get away with a 10uH inductor?
Is there a better way to get the four outputs in phase or anti-phase?
Thanks