[mc1322x] econoTAG USB power trace width

[Mariano Alvira]

On Mon, Mar 29, 2010 at 02:07:07PM -0400, Andrew Ashworth wrote:
> Hey,
> I was wondering if anyone knew how wide+thick the power traces that run to the
> D+ and D- pads are. I'm trying to ballpark the max current I can pull over it
> safely.
> 
> -Andrew

Hi Andrew, 

D+ and D- are 12mil traces. USB_V+ is a 24mil trace. The board is 1oz
copper. 

There are several power supply options/tricks with this board:

JP13 is a regulated input up to 16V. A diode and pull-down protects
the USB port on your computer. 

JP12 is directly connected to the FT2232H and MC13224v. The max input
voltage here is 3v6. 

JP10 is shorted on the backside of the board. If you want to reduces
the leakage into the regulator (say you are running off a battery pack
in JP12) then you should cut that trace. (it says "CUT to use VBAT
only")

JP4 is also shorted on the backside and powers the FT2232H. You should
cut that too to save 80mA when on battery. 

To use the buck inductor cut JP27 on the backside. Populate D2 and L1.

Shorting JP11 will adjust the regulator to output 3v56 instead of
3v29. You'd want to do this if you are using JP13 and the buck
inductor.

-Mar.