Powering custom Teensy 3.2 from 9v 500ma wall adapter

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I have a custom Teensy design using a MCP1825S-3302E/DB as a power regulator. I have a request from customers to allow the device to be powered from a 9v 500ma wall wart, which is typical for audio gear.

I searched the forums here but couldn't really find anything. Anyone have any idea how I should drop that 9v down for interfacing with the MCP1825? Should I be looking for a different regulator? Any tips or schematics would be great.

All comes down to the power needed. If you need the 500mA that the MCP1825 can allegedly produce (with an ideal PCB layout and so on) then have at least 2 choices:

1) Find a more suitable voltage regulator that can handle the higher input-output voltage delta (i.e something like the LD 1117 series). Pay attention to heat management though.
2) A DC-DC switchmode power supply like the Recom ROF-78xx series, which can either take you down to 3.3V directly (if your application can handle the ripple) or 'just' 5VDC and then the MCP1825 can take over.
Maybe something like this? Not sure about the caps. Probably have more than I need.

That's certainly one way to do it. However, I wonder if you have the polarities on the power jack reversed. Most jacks are positive on the inside, GND on the outside.
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