Alright, so I'm making a small interface board to connect two USB devices to a single USB port on a host machine. I added the following:
2-port USB hub
FTDI Virtual COM port (the peripheral is a serial display).
ESD/EMI protection for the USB ports
1 connector for the other peripheral (USB Keypad)
The USB hub requires 3.3V supply, so I added an LDO MIC5209-3.3YS TR to go from 12V to 3.3v, this guy appears to be working fine.
For the VBUSes and the Serial display I added another LDO MIC39100-5.0WS TR to go from 12V to 5V. I measured the current consumption it is around 310mA.
Everything appears to be working fine, but I noticed that the board was getting warm, so I took out my Fluje 561 and measured a MAX temperature of 125F over the 5V LDO. I might have messed up the layout and I might be missing some copper that should be there to aid in temperature dissipation, although I am not drawing the maximum for the LDO, which according to the datasheet it is 500mA.
This is my schematic:
![](http://i.imgur.com/zM0WgrM.png)
And this is a 3D View of that area:
![](http://i.imgur.com/UIYUKAw.png)
This the top layer view (the top layer is copper flooded with GND)
![](http://i.imgur.com/Z8n2pZj.png)
This is the bottom side of that area:
![](http://i.imgur.com/XVH17oK.png)
This is a top view of the whole board:
![](http://i.imgur.com/8vD9RlN.png)
And bottom:
![](http://i.imgur.com/WMrDz8b.png)
12V comes in from the left side via J1, and it goes to a Ferrite Bead FBMH2012HM121-T (rated at 2A), I've highlighted 12V here:
![](http://i.imgur.com/puKGYXB.png)
And this is 5V0:
![](http://i.imgur.com/I2NUjI9.png)
![](http://i.imgur.com/AQXlXqe.png)
What did I miss?