afpineda
commented
1 year ago As far as I know, there are two answers: YES and...NO
NO
The built-in power regulator allows any input voltage from +5V to +7V more or less (don't know the exact value). The greater the voltage, the higher the wasted power and the higher the dissipated heat. In your case, to add a second power regulator is twice the power waste and much more heat. Not recommended
YES
Going from +24V down to +3V3 means a lot of heat and wasted power. However, if you have no choice, just ignore the built-in power regulator at all, since the AP63205 is +3V3 output-capable. Wire such an output to VDD3V and GND as usual. Leave ' 5V' unconnected.
Be warned: never attach 5V nor the USB cable along with the external power source at the same time or you will damage the devkit board.
This is just my opinion. Didn't test myself
lewisxhe
Can I just chuck 5V +/-5% into the 5V pin? I want to power the T-QT Pro from 24V, so was going to use an AP63205 which seems to fit the bill. I would appreciate any advice in this respect. I am aware the 3.3v model may be more appropriate, and could be put into the 3.3V pin probably safely, but I want 5V for other projects so will buy a few and therefore 5volts is more useful.