Powering the Boron at 3.3V

boron
Tags: #<Tag:0x00007fe21fb8e120>

#1

I have a power supply that drops input voltage to 3.3V. The 3.3V is fed to the vusb pin on the Boron. The data sheet says the Boron should power up but I don’t get anything. The xenon and argon both come on fine when placed on the board.

I have tried using a battery to allow the Boron to turn on, and then set the input voltage limit to 3000 in software. However, that still does not keep the Boron powered when I unplug the battery.

Is the datasheet incorrect or am I missing something?


#2

The recommended voltage on VUSB is 5.0V.

It’s not recommended to power the Boron at 3.3V because the cellular modem requires a minimum of 3.6V for operation.

You can’t charge a 3.6V LiPo at 3.3V, so that won’t work, either.


#3

I just saw in the datasheet that I misread the inputs. It says V3v3 can have an input voltage of 3.3, but even moving to that pin the modem won’t have enough power to operate? Looks like I am ordering some 5v psus!


#4

The 3V3 pin is an output on the data sheet see here

image

So you need to supply 5V to VBUS to in order to run the module correctly and charge the required LiPo