eFuse Click

How does it work?

eFuse Click as its foundation uses the STPW12, a programmable electronic power breaker optimized to monitor the input power from STMicroelectronics. The device is designed and optimized to work on 12V power rails, even if the operating supply voltage can range from 10.5V to 18V. Connected in series to the power rail, it can disconnect the electronic circuitry on its output if the power consumption overcomes the programmed limit. The intervention threshold is programmed by the resistor connected by the RSET terminal. When this happens, the STPW12 automatically opens the integrated power switch and disconnects the load.

The overcoming of the power limit threshold is signaled on the monitor/fault pin on the onboard header pin labeled as VMON. The monitor/fault pin is proportional to the power, continuously present on the pin, and provides two valuable signals for the real-time control of the device and application status. After a particular delay time, programmable by the user, the STPW12 automatically tries again to close the internal switch and re-connect the load.

eFuse Click communicates with MCU using two GPIO pins routed on the PWM and RST pins of the mikroBUS™ socket labeled PWM and EN. The device can be enabled or disabled through a dedicated Enable (EN) pin with a direct PWM mode, which can be achieved through an external PWM signal. In this mode, the device’s internal power switch can be driven ON/OFF by an external PWM signal, provided to the PWM pin of the STPW12 (square wave, maximum 2kHz, duty cycle 20% – 100%). This approach allows the user to optimize the design power distribution system in terms of accurate power control, choice of isolation material, safety improvements, such as the reduced risk of flammability and easier qualification and certification flow.

This Click board™ can be operated only with a 3.3V logic voltage level. The board must perform appropriate logic voltage level conversion before use with MCUs with different logic levels. However, the Click board™ comes equipped with a library containing functions and an example code that can be used, as a reference, for further development.

Specifications

Pinout diagram

This table shows how the pinout on eFuse Click corresponds to the pinout on the mikroBUS™ socket (the latter shown in the two middle columns).

Notes	Pin					Pin	Notes
	NC	1	AN	PWM	16	PWM	PWM Signal
Enable	EN	2	RST	INT	15	NC
	NC	3	CS	RX	14	NC
	NC	4	SCK	TX	13	NC
	NC	5	MISO	SCL	12	NC
	NC	6	MOSI	SDA	11	NC
Power Supply	3.3V	7	3.3V	5V	10	NC
Ground	GND	8	GND	GND	9	GND	Ground

Onboard settings and indicators

eFuse Click electrical specifications

Software Support

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

Library Description

The library covers all the necessary functions to control eFuse Click board™. Library performs a standard SPI interface communication.

Key functions:

• void efuse_enable_device ( uint8_t en_dev ) – Enable the device function.
• Enable the device function. float efuse_get_voltage ( uint16_t adc_data ) – Get voltage function.
• float efuse_get_power ( uint16_t adc_data, float input_voltage ) – Get power function.

Examples description

The application is composed of three sections :

• System Initialization – Initializes SPI, set RST, CS and PWM pin as outputs, begins to write log.
• Application Initialization – Initialization driver enables – SPI and enable the device, also write log.
• Application Task – (code snippet) This is an example that demonstrates the use of the eFuse Click board. In this example, we monitoring and display ADC and voltage ( mV ). Results are being sent to the Usart Terminal where you can track their changes. All data logs write on USB uart changes approximately for every 3 sec.

void application_task ( )
{
    adc_data = efuse_read_data( );
    
    mikrobus_logWrite( "     ADC Monitor :     ", _LOG_LINE );
    mikrobus_logWrite( "- - - - - - - - - - - -", _LOG_LINE );
    mikrobus_logWrite( " ADC     = ", _LOG_TEXT );
    WordToStr( adc_data, log_demo );
    Ltrim( log_demo );
    mikrobus_logWrite( log_demo, _LOG_LINE );
    
    voltage = efuse_get_voltage( adc_data );
    
    mikrobus_logWrite( " Voltage = ", _LOG_TEXT );
    FloatToStr( voltage, log_demo );
    mikrobus_logWrite( log_demo, _LOG_TEXT );
    mikrobus_logWrite( " mV", _LOG_LINE );
    mikrobus_logWrite( "-- -- -- -- -- -- -- --", _LOG_LINE );
    
    power = efuse_get_power( adc_data, input_voltage );
    
    mikrobus_logWrite( "    Power Monitor :    ", _LOG_LINE );
    mikrobus_logWrite( "- - - - - - - - - - - -", _LOG_LINE );
    mikrobus_logWrite( " Power   = ", _LOG_TEXT );
    FloatToStr( power, log_demo );
    mikrobus_logWrite( log_demo, _LOG_TEXT );
    mikrobus_logWrite( " W", _LOG_LINE );
    mikrobus_logWrite( "-----------------------", _LOG_LINE );
    
    Delay_ms( 3000 );
}

The full application code, and ready to use projects can be found on our LibStock page.

Other mikroE Libraries used in the example:

• SPI
• UART
• Conversions

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. The terminal available in all MikroElektronika compilers, or any other terminal application of your choice, can be used to read the message.

mikroSDK

This Click board™ is supported with mikroSDK – MikroElektronika Software Development Kit. To ensure proper operation of mikroSDK compliant Click board™ demo applications, mikroSDK should be downloaded from the LibStock and installed for the compiler you are using.

For more information about mikroSDK, visit the official page.