I have designed a development board for the xmega32a4 and wanted some feedback.

The board has 40 pins and has a similar design to our om644p - i.e. it includes a 40-pin 600 mil DIL format, xmega32A4, USB socket, FTDI USB/RS232 converter, power LED, USB TX/RX monitor LEDs, 3 port I/O monitor LEDs, a 16 MHz crystal, and a bootloader for easy downloading of software instead of using a PDI programmer. The crystal can be used with the PLL generator to support up to 32MHz. The board can be powered from external 3.3V source, USB or an external 4.6-18V source via the on-board 600mA 3.3V LDO regulator. Pins are provided so that a PDI capable programmer could be used to replace the supplied bootloader with any user code.

The picture below is an annotated Eagle 3D rendering of board. It is almost correct but only shows the outline of the mini-B USB socket and the SOT89 3.3V regulator. All of the port I/O pins (A, B, C, D, E) are available on 32 I/O pins and the remaining 8 for power, reset/PDI_CLK, and TXD/RXD/ATN are in the "Basic Stamp" compatible format.

--Mike

What is the maximum input voltage the on-board regulator can take while still supplying an average of 500mA or so? This is a nice alternative to the minimal current supply capabilities of the previous devices. Is the trace between the reg and the VCC pin capable of carrying a few hundred mA to external circuitry?

This looks like a great way to break-in to the XMega family. And it looks like a great way to upgrade to XMega for existing applications!

I presume that the bootloader will be reasonably compatible with the other OM devices?

-Tony

In my documentation for the other devices that use this linear regulator, I do not recommend much above 250mA because of the limited ability for heat sinking of the disappiated power. This is still far superior than the usual 100mA on other boards. I also do not recommend using much above 10V if you want to be safe. For larger requirements, an external switching regulator is better bet.

The xmega bootloader will use the same download protocol as the other Oak Micros bootloaders so that the same downloader software can be used.