Hi

Nice to meet you after viewing your profile i am Jacinda, from (jakarta) indonesia,

i have a project discussion with you please email me on: (jacinda.seiler@yahoo.com)

So, while this is a high frequency converter that does not need nearly as much energy storage (i.e. inductor size), this particular 0805 is still too small for the full 1.2A. Like SMD caps, manufacturers like to, erm, overrate inductors in technically valid ways. There are actually two current ratings for most inductors, and they can differ substantially depending on geometry: rated current until overheating (relevant for chokes - that's the 1.2A in this case, and the most commonly reported number...because it's bigger), and rated current until saturation (relevant for most other applications). Saturation occurs when there's too much magnetic field for the actual core material to handle, and the effective inductance actually falls. In this inductor, the inductance falls from 2.2uH to 2uH around 300mA, and all the way down to ~.7uH at 1A, where I'm fairly certain the converter would stop functioning (See page  27 of http://www.murata.com/~/media/webrenewal/support/library/catalog/products/inductor/chip/o05e.ashx)

If you've already ordered parts, a quick way to rig it to work at high currents for testing may be to put a few of those inductors in series and parallel (2x series, 2x parallel) for about twice the actual handled current (need to double check my logic there, not 100% sure).

Thanks for the tip. 

I just finished programming my toaster oven, and will be testing these boards shortly. I'll let you know how it goes, temperature and on the oscilloscope. From the datasheet it looks like the inductor maxes out at 1.2A, but may operate more optimally at lower currents. This may not be the power supply for your project that runs at 1.2A continuous, that's the max rating of the parts. This is designed around the DIP8 form factor, the current it can handle will be a function of that size constraint.

How are getting 1.2A from an 0805 size inductor?

Right! Digikey parts search. It's the smallest one I found rated at 1.2A. 'tronics these days man, so optimized. Though I'm still waiting on the board from OSHpark, so we'll see!