Problem with power on when a battery is below 3.0 V and connected ti main power

Posted on by Admin

11 thoughts on “Problem with power on when a battery is below 3.0 V and connected ti main power”

  1. If the telit is connected to main power but if
    it has connected a battery below 3.0 V, it starts to the batt charge
    process and delays the execution of python.

    My problem is that the PY is not executing until the voltage in
    the battery is over 3.0 V. Sometimes it takes 2 o 3 minutes  to starts
    executing the python code. Is this behavior normal or we have something
    wrong in our circuit?

     

    Regards,

     

    Luis

        1. The Extended Operating Voltage Range of the module in question is from 3.22V to 4.50V, so the behavior encountered from the customer is normal
          In similar cases we suggest to monitor from python script the voltage present on VBATT pin (by AT#CBC command) and then if the voltage falls below
          3.3V signal that is required the battery charging.

          1. Cosmin,

             

            If we have 4.3 V In CHARGE pin and we have a Li-ion battery with voltage below 3.0V connected to VBATT then the python code doesn’t execute until the voltage in VBATT is over 3.15 V ( It takes around 2 minutes until the telit module recharges the battery to a voltage over 3.15V). 

            Note that : 

            If there is no battery the python code executes normally

            If the Voltage in the Li-ion battery is 3.15 or greater the python code executes normally

             

            Is that behaviour normal?

             

             

             

          2. Cosmin,

             

            This is the case:

            We turn our power supply off then we turn power supply ON and then we can measure:

            The voltage in CHARGE PIN is 4.2 V,

            We have a
            Li-ion battery with voltage under 3.1V connected to VBATT

             

            In that case the
            python code doesn’t execute quickly,
            It takes around 2 minutes until the telit module recharges the battery
            to a voltage over 3.15V

            Note that : 

            If there is no battery the python code executes normally

            If the Voltage in the Li-ion battery is 3.15 or greater the python code executes normally

             

            Is that behaviour normal?

             

          3. VBATT is the main power supply and this dictates the behavior. More, the CAHRGER input, as per Hardware User Guide, must be limited to max 400 mA and is not designed to be used as the main power supply.

             

             

          4. Our problem is if the battery is damaged then the telit doesn’t turn on even if it has main supply. So I thought we must have something wrong in our circuit

          5. I assume you have the battery connected to VBATT and the 5V supply to CHARGE pin. 

             

            where is the main supply connected and what is the voltage? 

          6. You are correct, we have the battery to Vbatt and 4.2V to CHARGE pin.

            Is it possible to connect 4.2 V and the battery to VBatt  ?

             

             

          7. Hi Luis,

             

            first of all 4.2V is a under CHARGER specs. 

            Charger input range is 5-7V, typical 5.5V. 

             

            In any case you cannot connect both 4.2V and battery to VBATT at the same time. You should switch between one and the other.

             

            It is correct that the python script doesn’t start when the battery voltage is 3.0V. As you can see in the GE863-GPS docs, the minimum voltage is 3.22V. Below this voltage, the module is not powered on.