Hello:
As we know, the Micro USB is not a “industrially reliable” connection.
What other alternatives are possible from MangOH Red to connect an external power supply? Are there any pins from RPi connector or anywhere else that can be connected to an external 5V DC?
Thanks Ashish.
Do we need to feed external power supply through diodes to ensure correct polarity; or is there a smarter way of doing this in MangOH itself?
No you dont. Only source of input power will be Rpi connector. Make sure CN804 jumper is not installed.
On the other hand if you dont want to make a hardware mod on the board, you can do the following:
a. Make sure CN804 jumper is not installed.
b. plug +5V input to middle pin of CN804
c. Connect ground to Rpi ground pins.
Thanks Ashish.
I understand MangOH has internal built-in circuitry to protect the board from polarity reversal of the external power supply.
Good to know.
Why do you think Micro USB is not a “industrially reliable” connection?
Could you share your experience?
Some USB hub with external power(like attached picture) may help you.
They all have qualified & safe. Also, it provide a separation between your devices to computer. Once something wrong(electrical), your computer(e.g. NB) still keep in safe.
Another choice, you could use battery port(4.2V max.) to apply at CN802.
Except battery, you also able to uae DC power supply (3.4V ~ 4.2V). For me, I always use 4.0V.
Of cause, necessary confirm the polarity before use.
Hello,
We implemented an alternative solution by connecting an additional regulator to the battery input. If you set the voltage of this regulator to 4.5v it works just fine.
There are many of those available in the market at a low cost.
In this way you can maintain the usb power input and the jumper connected.
See below some images.
Regards,
Enric
Yes, thanks for your share.
Note the max. battery level is below 4.2V(Li-ply). It is necessary to avoid overdrive.
We need to consider a voltage drop & ripple noise performance of regulator. There issue are directly affect mangOH board.
Also, it lose a power supply level monitoring function, because your board has been separated with outside by regulator.