keyless wrote:Hi guys, can you specify the power consumption in mA?
If i connect a 3.7V power supply to Vbat how much mA the FONA needs in your max use?
Thanks!
I pulled out the data sheet the other day and it says the Sim Com chip consumes 18ma when idle, and when transmitting it will range from 100-200+ mA depending on which frequency band its working on. I guess it can spike and pull up to 2 amps at times also. The manual says the voltage needs to stay above 3.2v during these spikes or the chip could risk turning off from under voltage.
The LED on the board that Adafruit made consumes 5 ma also. The Blue LED.
Hi - Is there a way to easily determine if the Feather FONA is running on USB power, of off the LiPo.
VUSB pin remains high (when the usb power is disconnected).
Context: I am using the FONA module to send an SMS when the power trips (a really simple application).
Have a 5v relay between VUSB and GND switching a GPIO pin high if the power bails.
The thing to do is to set up a resistive divider on VUSB, and connect the output to an analog input pin. Connect 2 100k resistors in series between USB and GND. Tap a line from the junction *between* the two resistors to Digital 10 (aka Analog 9). Use the following code snippet to read the voltage. When you're on USB, the voltage will be 5. When on battery, the voltage will be 4.4 or lower.
#define VBATPIN A9
float measuredvbat = analogRead(VBATPIN);
measuredvbat *= 2; // we divided by 2, so multiply back
measuredvbat *= 3.3; // Multiply by 3.3V, our reference voltage
measuredvbat /= 1024; // convert to voltage
Serial.print("VBat: " ); Serial.println(measuredvbat);
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I'm working on project and I need to use Fona sms module to send data. My question is can I use another power source with USB cable, but not Lipo battery. If so does it have a USB hookup ? Also, Is there any other product work with USA network