Powering the Boron at 3.3V

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?

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.

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!

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

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