2 Replies Latest reply on Oct 5, 2017 3:32 PM by inoue_tomohiro_1742091

    Cypress CYW4339 internal LPO usage

    hao.meng_2466041

      The design for our WiFi uses the Murata LBEH5HMZPC part which uses a Cypress CYW4339

       

      We were not able to get the WiFi part operating until we added an external 32kHz clock to pin 36 (LPO_IN).

      According to the CYW4339 datasheet the device uses a 32kHz clock to control power sequencing.
      This can either be the internal oscillator or an external oscillator.

      We were expecting to use the internal oscillator but cannot determine how to make it operate.
      Adding the external oscillator allows the part to operate correctly.

       

      The LBEH5HMZPC datasheet does not specifically state anywhere that an external oscillator is required but every diagram shows the LPO as an external input.

       

      The Cypress CYW4339 datasheet does not tell us how to force operation from the internal LPO instead of the external LPO input.

       

       

      Is it possible for the LBEH5HMZPC to operate using the internal LPO and if so how we force this mode of operation?

       

      What is the TCXO reference frequency used in the LBEH5HMZPC?

      Is this data for the LFB182G45SG9A272 filter recommended in the Murata LBEH5HMZPC datasheet?

      Where do we get the latest firmware for the LBEH5HMZPC which is loaded by the Linux driver
      (fw_bcmdhd.bin, fw_bcmdhd_apsta.bin and fw_bcmdhd_mfgtest.bin). 

       

      And may I know where I could find the latest versions of CYW4339 firmware?

       

      Thanks a lot!

      Hao