multiwii schematics, circuit and power flow discussion

[captaingeek]

Hi, I'm having some trouble understanding the power flow of this circuit:

http://multiwii.googlecode.com/svn/trun ... on%201.png

Question section 1:
So when bench testing, you plug in through ftdi / usb, is 5v power coming over RAW only? Is it then also coming out VCC as well?? Or is power being provided by VCC only in this instance? is it necessary to jump VCC and RAW when testing over USB?

My ACCL is not reading. I only get ic2 errors when I enable it in software. My gyro's read great and are hooked up according to this circuit along with the acc.

Question 2:
If you want to test your FC with a battery / BEC attached at the same time, how do you prevent the voltage from back flowing into the USB or vice vs. to prevent burning something out?

In this one, what does * besc + and gnd wires should not be run in parallel mean? Why shouldn't they?

http://multiwii.googlecode.com/svn/trun ... iagram.png

http://multiwii.googlecode.com/svn/trunk/Doc/Diagrams/

[copterrichie]

You get what you pay for. Ha!

[gompf-2]

... Is it then also coming out VCC as well?? Or is power being provided by VCC only in this instance? is it necessary to jump VCC and RAW when testing over USB?

Imho it´s a mistake to power the Promini by 5v through raw. If you power by 5V then trough Vcc. 5V trough raw will never be stable as there is no room for the vreg to regulate-> voltage depends on diode voltage drop trough the vreg ic/depends on load. May have influence on the ADC

There is no logic to use alternating power sources, I never tried to apply both voltages and never will . If you use raw pin for promini supply it "shoud" work. Maybe this is what was intended in this design.

Question 2:
If you want to test your FC with a battery / BEC attached at the same time, how do you prevent the voltage from back flowing into the USB or vice vs. to prevent burning something out?
In this one, what does * besc + and gnd wires should not be run in parallel mean? Why shouldn't they?

See above. The power wires should be twisted to lower the magnetic interference.

[captaingeek]

You get what you pay for. Ha!

absolutely! and i dont see your name in the list of sponsors.

[copterrichie]

You get what you pay for. Ha!

absolutely! and i dont see your name in the list of sponsors.

But I am not the one having issues. Ha Ha!!!

BTW, I have donated but I don't have to prove that to you. Ha!

[copterrichie]

LOL, Just HAVING Fun he says. Ya right!