Reported Voltages

1

I get the brown-out & hard reset often, but if I understand Rob’s explanation from another post it is expected within 15 minutes of connection. However, I am curious as to where these voltages numbers come from in the json:

{“method”:“boot”,“text”:“boot (brown-out & hard reset [17494])”,“voltage”:4.3476562,“voltage_mode”:“usb”}

I’m feeding 5 volts in to the VUSB pin and measure it as 5 volts at the board, but this shows much less. Why?

3

Hi @sn13TX,

What’s likely happening is the voltage value reported in _health.qo is the VMODEM_P rail voltage, not the input voltage. Since it measures the voltage at the modem power supply rail downstream of the regulation/protection circuitry, you’re always going to see a lower value than your input voltage.

Rob