Dongle Edition. External power source
It is recommended to use these pads/pins to connect an external power source:
The Dongle's operating range is:
- supply voltage should not exceed 6 Volt
- supply voltage should not drop below 3.1 Volt
Your power source should supply DC with little or no AC component - a lot of HF noise over power lines will definitely ruin the Dongle's GNSS and/or ISM RF receiver(s) performance.
Electric current consumption is:
- about 40-45 mA of active average
- with short peaks of up to 180 mA when the board is transmitting over RF circuit
- 0.55 mA in 'deep sleep' state
The peak current value depends on S76G built-in RF component's (SX1276) transmit power setting, thus take in account
- + 120mA @ +20dBm
- + 90 mA @ +17dBm
- + 29 mA @ +13dBm ( EU legal limit for 868.2 - 868.4 MHz )
in addition to 'active average' value specified above.
If you are supplying power from a battery source, you may consider to utilize onboard ADC circuit. SoftRF firmware is able to monitor supply voltage and will shut the device down if the voltage drops below a threshold level.
The threshold level value is 3.2 Volt.
To activate the monitor you need to short Vs (5V) and ADC pads of the board's pin header:
