Low Power Implementation and Current Measurement Method for CYBT-343026- EVAL – KBA223800

Version 2

    Version: **

     

    Question:

    How can I enable Low Power mode in on CYBT-343026-EVAL? How do I measure the current?

     

    Answer:

    The CYBT-423028-EVAL kit includes a fully integrated and certified Bluetooth Smart Ready wireless module (CYBT-343026-01).

    This KBA explains how to enable Low Power mode using a sample application; a modified hello_sensor (hello_sensor_lowpower) sample application.

    Follow these steps to enable Low Power mode in the sample application:

       1. Include the header file wiced_power_save.h in the application project of WICED® Studio SDK.

    #include “wiced_power_save.h”

     

       2. Declare a callback function which is called by the stack at every opportunity to put the CYBT-343026-01 module to Low Power mode.
               static uint32_t    LPB_power_save_approve_callback(void);

     

       3. Register the callback function in the initialization function of the application project.

    wiced_power_save_register_approve_cback(LPB_power_save_approve_callback);

     

       4. Call the below function at the end of initialization to enable Low Power mode operation.

    wiced_sleep_config( WICED_TRUE, NULL, NULL );

     

       5. Implement the callback function to return ‘1’ at every possible opportunity to send the device to Low Power mode.

    uint32_t LPB_power_save_approve_callback()

    {

         return 1;      /* Return 1 to approve going into low power mode */

    }

     

    Here are a few options to optimize the power consumption of the CYBT-343026-01 module:

    • Disable the timers in the application project or increase the timeout value based on the application requirement.
    • Comment or remove UART initialization if the application does not require UART operation in the final product.

    // wiced_transport_init( &transport_cfg );

    • Make sure the unused GPIOs are in HI-Z mode to avoid leakage current.
    • Turn OFF all switches on SW4 (HCI_UART) and SW5 (PUART) while measuring current in CYBT-343026-EVAL. Make sure all switches on SW4 (HCI_UART) are ON for firmware download.