Dear TI Expert,
I have a LM2587 design, which is based on the datasheet.
After I run the same parameters on the Webench, the result is pretty scary. the inductor in the datasheet is 33uH, but in the webench is 330uH. it is a big difference, something much be wrong.
Hello David,
The difference between these designs is the assumption on the allowed ripple current. The device has external compensation, so as long as the compensation fits to the LC filter and the peak current in the application is not higher than the current limit, there are a lot possible inductors that can be used. You could for example use the power stage designer to play with the external components: 
You will observe that both designs can work, the one with the 33 uH inductor creates a higher current ripple, but this is in general not a big problem.
It seems that Webench limits the current ripple to 10%.
In general I would recommend you to check out LM5157 which is possibly the right fit for your application.
