Hey, so I was getting some advice on this board in a thread a few down in this forum. I’m finishing up the layout and want to send it out to a fab house soon, probably batchpcb.
Can you guys give this a look and see if there’s anything that needs reworking?
Here’s what we have: The top plane is Vcc, the bottom is GND. In the top left is a reset button and ISP header (atmel’s PDI interface… the 5V that comes in needs to come down to between 1.6 and 3.6 for the ATXMega that I’m using, thus the two series diodes. I use that trick a handful of times). Below those are the ZIF connector for an LCD screen, a “power out” header, the TQFP64 chip is the ATXMega256A3. Below that is an accelerometer and microSD card socket, both on an SPI bus. Then at the bottom left, battery power in, 3.3V regulator, and a power indicator. The bottom right is two headers for hardware debugging and verification. Top right are two USB connectors, one as a fake COM port, the other as a low-speed USB device. Both USB ports provide power via two series diodes. USB being fairly reliably 5V, i figure this should be OK… bad assumption?
The middle of the right-hand side of the board is a GPS unit, the MN5010 in fact. There’s a side-mount SMA connector on the right edge of the board with both top and bottom contacts grounded. Does that look OK? the distance from the edge of the board to the GPS receiver is about .3"
EDIT: just discovered a logic-level problem between the GPS unit and the microprocessor. I’m gonna throw a Venus634FLPx on instead of the MN5010, but it should be generally the same otherwise
EDIT 2: i just found out that the reason i can’t find the accelerometer i want to use anywhere is that it’s not being made anymore. Replacing it with the ADXL345…](ImageShack - Best place for all of your image hosting and image sharing needs)