5 Replies Latest reply on Aug 6, 2009 9:18 AM by saic_96

    Output Power

    marcus.hamberg
    marcus.hamberg Aug 6, 2009 9:18 AM
              Hi,   
         
      Is +4 dBm output power possible with internal amplifier on CYRF7936? I ask because all info in datasheet and such says it should be but if you look in CyFi modules config file the max output power is limited to PA6 which is 0dBm both in hub and node. A clarification would be much appreciated.   
         
      Best Regards   
         
      /Marcus   
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        • 1. Re: Output Power
          saic_96
          saic_96 Apr 8, 2009 11:21 AM (in response to marcus.hamberg)
                  Hi Marcus,   
             
          Yes you are right . +4dbm is the maximum output power without using an external Power amplifier. And by using external amplifier CYFI works upto 20dbm.   
             
          Regards,   
          Sai   
          • 2. Re: Output Power
            JamesD_81
            JamesD_81 Apr 8, 2009 11:27 AM (in response to marcus.hamberg)
                    Small clarification, the CY3271 PSoC FirstTouch Starter Kit with CyFi Low-Power RF works up to 20dBm using the off-chip power amplifiers in the kit. The transceiver can support more than that in terms of off-chip power amps, your limitation here will first be FCC/ETSI or other governmental radio regulations before it's the transceiver.   
            Regards,   
            Jim   
            • 3. Re: Output Power
              JamesD_81
              JamesD_81 Apr 8, 2009 11:33 AM (in response to marcus.hamberg)
                      Marcus,   
              To answer your other question about max power in the CyFi modules, if you go into the CYFISNP_Config.h file (or YOURMODULENAMEFORTHISUSERMODULE_Config.h) you should see a section of #define's setting the available PA levels. If you have an external PA, then update the "#define PA_LEVEL_USED PA4_PLUS" line to whatever max PA level you want/need (max would be "PA7_PLUS").   
              Regards,   
              Jim   
              • 4. Re: Output Power
                marcus.hamberg
                marcus.hamberg Apr 14, 2009 4:12 AM (in response to marcus.hamberg)
                        Ok, thanks for your answers.   
                   
                I still wonder though why the CyFi user module limits the output power to 0dBm when using internal amplifier, when you say +4dBm should be possible with internal amplifier only.   
                   
                Regards   
                   
                Marcus   
                • 5. Re: Output Power
                  saic_96
                  saic_96 Aug 6, 2009 9:18 AM (in response to marcus.hamberg)
                          No , it does not limit the power to 0dbm . You will be able to use till 4dbm. Please refer the variable PA7 in the CYFI firmware for this purpose.   
                     
                  Cheers,   
                  Sai