Current 14 Click

Current 14 Click is a compact add-on board designed for precise current measurement without direct contact. This board features the BM14270, a magnetic current sensor IC from ROHM Semiconductor. It uses a coreless, non-contact magnetic impedance (MI) sensor, ensuring low power loss and accurate current detection. It communicates through a 2-wire I2C interface, offering a 14-bit digital output with a measurable magnetic range of ±280μT and sensitivity of 0.045μT/LSB. The board includes an alert interrupt pin (ALR) that indicates data readiness, streamlining real-time data acquisition for the host MCU.

Click Product page

Click library

• Author : Stefan Filipovic
• Date : Jun 2024.
• Type : I2C type

Software Support

We provide a library for the Current 14 Click as well as a demo application (example), developed using MikroElektronika compilers. The demo can run on all the main MikroElektronika development boards.

Package can be downloaded/installed directly from NECTO Studio Package Manager(recommended way), downloaded from our LibStock™ or found on Mikroe github account.

Library Description

This library contains API for Current 14 Click driver.

Standard key functions :

• current14_cfg_setup Config Object Initialization function.

  void current14_cfg_setup ( current14_cfg_t *cfg );

• current14_init Initialization function.

  err_t current14_init ( current14_t *ctx, current14_cfg_t *cfg );

• current14_default_cfg Click Default Configuration function.

  err_t current14_default_cfg ( current14_t *ctx );

Example key functions :

• current14_calib_offset This function calibrates the zero current offset value.

  err_t current14_calib_offset ( current14_t *ctx );

• current14_calib_resolution This function calibrates the data resolution at the known load current.

  err_t current14_calib_resolution ( current14_t *ctx, float calib_current );

• current14_get_current This function reads the input current level [A].

  err_t current14_get_current ( current14_t *ctx, float *current );

Example Description

This example demonstrates the use of Current 11 Click board by reading and displaying the input current measurements.

The demo application is composed of two sections :

Application Init

Initializes the driver and calibrates the zero current offset and data resolution at 3A load current.

void application_init ( void )
{
    log_cfg_t log_cfg;  /**< Logger config object. */
    current14_cfg_t current14_cfg;  /**< Click config object. */

    /** 
     * Logger initialization.
     * Default baud rate: 115200
     * Default log level: LOG_LEVEL_DEBUG
     * @note If USB_UART_RX and USB_UART_TX 
     * are defined as HAL_PIN_NC, you will 
     * need to define them manually for log to work. 
     * See @b LOG_MAP_USB_UART macro definition for detailed explanation.
     */
    LOG_MAP_USB_UART( log_cfg );
    log_init( &logger, &log_cfg );
    log_info( &logger, " Application Init " );

    // Click initialization.
    current14_cfg_setup( &current14_cfg );
    CURRENT14_MAP_MIKROBUS( current14_cfg, MIKROBUS_1 );
    if ( I2C_MASTER_ERROR == current14_init( &current14, &current14_cfg ) ) 
    {
        log_error( &logger, " Communication init." );
        for ( ; ; );
    }

    if ( CURRENT14_ERROR == current14_default_cfg ( &current14 ) )
    {
        log_error( &logger, " Default configuration." );
        for ( ; ; );
    }

    log_printf( &logger, " Calibrating zero current offset in 5 seconds...\r\n" );
    log_printf( &logger, " Make sure no current flows through the sensor during the calibration process.\r\n" );
    for ( uint8_t cnt = 5; cnt > 0; cnt-- )
    {
        log_printf( &logger, " %u\r\n", ( uint16_t ) cnt );
        Delay_ms ( 1000 );
    }
    if ( CURRENT14_ERROR == current14_calib_offset ( &current14 ) )
    {
        log_error( &logger, " Calibrate offset." );
        for ( ; ; );
    }
    log_printf( &logger, " Offset calibration DONE.\r\n\n" );

    log_printf( &logger, " Calibrating data resolution in 5 seconds...\r\n" );
    log_printf( &logger, " Keep the load current set at 3A during the calibration process.\r\n" );
    for ( uint8_t cnt = 5; cnt > 0; cnt-- )
    {
        log_printf( &logger, " %u\r\n", ( uint16_t ) cnt );
        Delay_ms ( 1000 );
    }
    if ( CURRENT14_ERROR == current14_calib_resolution ( &current14, 3.0f ) )
    {
        log_error( &logger, " Calibrate resolution." );
        for ( ; ; );
    }
    log_printf( &logger, " Data resolution calibration DONE.\r\n" );

    log_info( &logger, " Application Task " );
}

Application Task

Reads the input current measurements and displays the results on the USB UART approximately once per second.

void application_task ( void )
{
    float current = 0;
    if ( CURRENT14_OK == current14_get_current ( &current14, &current ) )
    {
        log_printf ( &logger, " Current: %.3f A\r\n\n", current );
    }
}

The full application code, and ready to use projects can be installed directly from NECTO Studio Package Manager(recommended way), downloaded from our LibStock™ or found on Mikroe github account.

Other Mikroe Libraries used in the example:

• MikroSDK.Board
• MikroSDK.Log
• Click.Current14

Additional notes and informations

Depending on the development board you are using, you may need USB UART Click, USB UART 2 Click or RS232 Click to connect to your PC, for development systems with no UART to USB interface available on the board. UART terminal is available in all MikroElektronika compilers.