Why does my DIY Barebones Arduino Due with SAM3x8E overheat on RESET press?

Question

I made my own diy "bare bones" Arduino Due in an embedded application. Basically I was making a portable Bluetooth headphone amplifier for a school project. The point of the MCU was to display battery information on a touchscreen LCD and to control volume with a digital resistor. Everything else on my board seems to work including Bluetooth. Since this was a prototype, I added a switch which would bypass the digital resistor and go to a normal pot for volume control, so I know everything on my board works except the SAM3x8E.

Here is the issue:

When I plug in the USB, the device does not get recognized by the PC at all. No COM ports are available in device manager. If I press the reset button, the chip gets abnormally hot. Uncomfortably hot to the touch! If you unplug power and plug it back in, even after waiting a second or two, it STILL starts getting hot. It's only after you power cycle and hit the ERASE button a few times that the chip finally stops overheating. Also, during this process, my 3v regulator drops out as if the chip is drawing too much current. (because the blue 3.3v led goes out)

After the power cycle, things go back to normal, and Bluetooth and the rest of my amplifier works fine. Can anyone take a look at my schematic and see if anything obvious is wrong? I am a little lost, any suggestions to help diagnose this issue?

Tomorrow, I will hook it up to an oscilloscope to make sure my crystals are providing clock. Any other test I can perform? I have triple checked this schematic against a number of Arduino Due and SAM3x8E reference schematics and do not see anything obviously wrong.

Here are the Eagle Cad Files:

Eagle Schematic File

Eagle Board File

Also some photos:

Here is the actual board (don't mind the unsightly makeshift jumpers):

Also, here is a schematic of the Power circuit:

Answer 1

I figured out my mistake the other day, and man was it a stupid one. The chip was soldered in 90deg in the wrong direction. Pin 1 should have been located at the top left. I got confused by the silk screen and the two larger dots, one of which I mistook for being the pin 1 marker. I did not think the orientation was an issue at all until it was pointed out to me. This chip will need to be replaced now most likely.

UPDATE:

I flipped the chip 90deg and it WORKS!!!! I haven't tested the full chip, I am sure this must have damaged at-least SOME parts of the chip? Still surprised it even gets recognized. Kudos Atmel!

Answer 2

You have "floating" reset and you cannot do like that with CMOS circuits, especially with their RESET lines. Your reset capacitor should be connected to the ground and through 1k resistor to 3.3v. Reset pin has to be connected between the resistor and the capacitor. Button has to go across cap.

Actually the right way to reset MCU is through Power-on-reset circuits (https://www.google.com/search?q=por+reset+circuit&ie=utf-8&oe=utf-8). These circuits release the reset only when supply voltage has reached certain value; MCUs don't like slowly rising supply voltage and start misbehaving.