From the Panda2 PDF manual:
2 part question:
Am I right in assuming both available 5V pins exposed on the Panda2 are the “Shield pins” referred to above?
Is it safe to power by said 5V pins (by supplying 5V from a stable switching external reg) and be plugged in to USB at the same time?
I believe only one 5V pin is available on the shield form factor pins. The other is on the double wide header on the end of the board. They are both labelled.
Out of curiosity, why would you want to use two power sources for 5V? Do you need precisely 5.0V available? More current? There is some dropout after the USB. I usually get about 4.8V (guessing from memory).
Shear convenience heh. I’m running a bunch of dynamixel servos on a 14.8V pack (16V at full charge) and already have a v-reg on board for something else that brings it down to a stable 5V (7-amp switching reg). Didn’t feel like putting a 6-9V reg on there too just for the Panda.
I don’t need 2 sources for 5V, but I need to know if I’m going to break something if I’m wired into the v-reg + battery and attached to my computer for programming at the same time. (again, shear convenience; I can just pull the battery off while I’m dumping code)
I’ve put 5 volts into the 5V pin and been connected to my laptop via USB at the same time. No problems whatsoever.
It maybe safer to use a diode between the 5v pin and your secondary 5v supply.
Dave.
Yeah I’m not saying it’s right, but I’ve powered my Panda ii with the 5v pin quite extensively. I designed a board that mates with the 40 pin connector, and it has a 5v regulator onboard so I figured why mess with a separate power supply.
I’ve debugged both over USB and Serial.