LarryP
Member
Maple folks,
First off, apologies if I missed this info somewhere in the Mini's docs:
On the Maple Mini, is there any access to the +5v rail from the USB connector (VBUS?)
If not, for the next Rev of the Mini, please consider adding at least a pad on the top that one can solder a small wire to. A through hole would be nice, but I'd rather have the pad sans hole, than no access to +5v from the VBUS signal from the USB connector.
Thanks,
LarryP
Member
Apologies for not checking the board art first. It looks like the VBUS signal is routed mainly on the top surface, and there are unobstructed runs long enough to take a thin wire, after scraping off the solder mask. There appears to be some space near pins 12 and 13; so a through hole could probably be added in later revs.
poslathian
LeafLabs
Good point, the first project I did on Mini this annoyed me right away. The next version will definitely have 5V available. Unlike on Maple, there is no power selection jumper, so the only way to power the board externally (useful in shields) and use the USB port was to throw a diode in between Vin and Vsupply (= usb 5v) which go to the regulators.
One thing you can do is remove the diode in front of Vin and use a solder blob to replace it. I have modified lots of boards this way.
another annoying thing is that there is no way to detach the regulators inputs from USB 5V, which means if you want to tap the usb 5V line and use the external input at the same time (for instance if you wanted to wire in a lipo charger and charge a battery over usb and use it for power) you have to disable the Minis regulators completely.
This can be done by removing both the Vin and USB 5V diodes and jumping their inputs together. This make Vin an output for usb 5V, leaves the regulator inputs floating, and then you can take that 5V on vin and send it to your own charger/regulator circuitry and dump the 2.4-4.2V back in on Vcc.
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