Joseph Smith wrote:
Anyone know if USB ports have power feedback protection.
All the details are in the USB spec. IIRC electrical is a separate chapter.
What I mean by that is if I use the LPCflasher as a inline flasher with a PLCC32 socket plug,
I don't understand this. Do you mean a socket or a plug?
flash the chip
Flash which chip?
and then power up the motherboard, I don't want the VCC's from the motherboard to short out the flasher and or the USB port from the host PC.
Make sure GND is connected across and you should be OK.
The 3.3V regulator I am using has a internal diode so I am not so worried about that. I am just worried about the power source 5V USB. I could always use a Schottky diode that will only drop the voltage by .6V, but I don't know if 4.4V will suffice???
Suffice for what? Look at the documentation for the regulator you're using to see what input voltage it needs.
//Peter