The LMR12010 is a step down DC-DC regulator that operates at the following switching frequencies: the LMR12010X at 1.6MHz and the LMR12010Y at 3MHz. The demo board is configured to convert 5V input to 1.8V output at 1A load current using the Y version. The tiny low profile thin SOT23 package allows the design to use less than 1 square inch of board area.
The circuit is configured with the boost diode connected to VIN. VIN must not exceed the maximum operating limit of 5.5V + VfD2 using this configuration. This will ensure that the voltage between the Boost and SW pins, VBOOST - VSW, does not exceed 5.5V for proper operation. Please see the LMR12010 datasheet for more information regarding this requirement.
The schematics at the end of the application note show how to reconfigure this demo board for various input and output conditions as discussed in the LMR12010 datasheet. Short or leave open the connections as indicated in the schematics. The above restrictions for the input voltage are valid only for the demo board as shipped with the demo board schematic.