4 Replies Latest reply on Jul 12, 2015 11:40 PM by rohit.kumar

    PRoC BLE Power calculation

    atul.singh

      I want to calculate minimum typical power needed for PRoC to be operate. For this I can list application wise needed power. i.e. power needed for BLE working, power needed for CPU in active mode. In this way I can plan for optimal use of battery.

         

      For this I have searched datasheet and AN92584 app note.
      I have following doubts/quarries :-
       

         

      1. On CYBL10X6X Family Datasheet :-
      a. On page 1 it is mentioned that "TX current: 15.6 mA at 0 dBm ■ RX current: 16.4 mA" , What is meant by that? , It is at what voltage? Is this amount of current needed for BLE Tx and Rx? Then why power calculator tool mentioned in app note display different current?
      b. table 5 :- Active 850 μA + 260 μA per MHz[1], At what vdd? Is it needed for CPU computation only without BLE?

         


      2. Power calculator tool gives typical current 27uA and 17uA for advertisement and connection respectively? What is the meaning of that current? In this case what is Vdd?

      Generally I asked for Vdd, because current needed is depends on Vin.
      Please help.
       

        • 1. Re: PRoC BLE Power calculation
          user_14586677

          1. On CYBL10X6X Family Datasheet :-
          a. On page 1 it is mentioned that "TX current: 15.6 mA at 0 dBm ■ RX current: 16.4 mA" , What is meant by that? , It is at what voltage? Is this amount of current needed for BLE Tx and Rx? Then why power calculator tool mentioned in app note display different current?
          b. table 5 :- Active 850 μA + 260 μA per MHz[1], At what vdd? Is it needed for CPU computation only without BLE?

             

           

             

          There is an extensive table of Vdd and Power consumption in the PRoC datasheet. It shows

             

          in pinout the seperate pins for the Radio (Vddr) and the general Digital (Vddd).

             

           

             


          2. Power calculator tool gives typical current 27uA and 17uA for advertisement and connection respectively? What is the meaning of that current? In this case what is Vdd?

             

           

             

          Vdd is the operating voltage applied to PROC. That spec is in its datasheet.

             

           

             

          Regards, Dana.

          • 2. Re: PRoC BLE Power calculation
            atul.singh

            @ Dana,

               

             Sorry for late reply but I didn't get answers. Pls explain.

            • 3. Re: PRoC BLE Power calculation
              user_14586677

              The datasheet is missing qualifier notes as you noticed. I would file a CASE on this to get

                 

              answers -

                 

               

                 

              To create a technical or issue case at Cypress -

                 

               

                 

              www.cypress.com

                 

              “Support”

                 

              “Technical Support”

                 

              “Create a Case”

                 

               

                 

              You have to be registered on Cypress web site first.

                 

               

                 

              Then post results back here for benefit of all.

                 

               

                 

              Regards, Dana.

              • 4. Re: PRoC BLE Power calculation
                rohit.kumar

                As Dana suggested, please raise a CyLink case for any issue that you see in the datasheets,

                   

                As for your questions, I would like to reply to some of them to best of my extent.

                   

                TX current of 15.6 mA and RX current of 16.4 mA (at 0 dBm) are the peak currents of the BLE radio in PRoC device. These peak currents will be observed whenever there is an BLE radio activity. For the rest of the time, these currents are not present. Also, as these are momentary currents, they are responsible for only fraction of the overall current requirements, depending upon the interval you choose.

                   

                As for the voltage, the device has an internal translator that drops the voltage from VDDR to 1.9V. Thus, the current values (only for radio) is at 1.9V. The other part of the device operates at the input voltage.

                   

                The current you see as part of power calculator calculations are averaged currents. As you know, all the BLE activities happen over some interval. If it is advertising, it happens every advertising interval set. If it is in connection, the interval == connection interval. The current values are averaged over 1 second interval, which is common for various low power BLE devices. In this 1 second, the device is active for only few milliseconds and in deep-sleep for the rest of the time. As the deep sleep current is ~1.3 uA, the averaged current (including the BLE TX and RX) comes about 17 uA for connection and 27 uA for advertisement (advertisement happens over three BLE channels, that is why it is more).