Optimize your systems, enhance safety, and achieve reliability with MAX17608 and STM32F446RE

Empowering innovation, one Amp at a time

Current Limit 6 Click with Nucleo 64 with STM32F446RE MCU

Published Oct 08, 2024

Click board™

Current Limit 6 Click

Dev Board

Nucleo 64 with STM32F446RE MCU

Compiler

NECTO Studio

MCU

STM32F446RE

Our current limiting solution is engineered to revolutionize safety and efficiency, offering precise control over current to ensure optimal performance while safeguarding your systems against overloads

Hardware Overview

How does it work?

Current Limit 6 Click is based on the MAX17608, a current-limiting device with an adjustable overvoltage and overcurrent protection feature from Analog Devices. The MAX17608 offers flexible protection boundaries for systems against input voltage ranging from 4.5V to 60V and limits the output load current to a programmed level (up to 1A). The devices also feature two internal MOSFETs connected in series, with a low cumulative RON of 260mΩ typical. Input undervoltage protection can be programmed between 4.5V and 59V, while the overvoltage protection can be independently programmed between 5.5V and 60V (default Click board™ configuration is 4.5V for UVLO and 14V for OVLO). Additionally, the MAX17608 has an internal default undervoltage lockout set at 4V typical. The current-limit switch is virtually ubiquitous in system control and provides a safe means for regulating the current delivered to a load circuit. It increases the load current to a programmed limit but no higher. Typically, the current limit is a

function of the voltage across an external resistor, and this voltage serves as the reference for an internal current-limiting amplifier. Replacing the resistor with a digital potentiometer allows you to program the current limit as performed on this Click board™. For this purpose, the digital potentiometer MAX5401 from Analog Devices, which communicates with the MCU via a 3-wire SPI serial interface, is used to set the resistance on the MAX17608 SETI pin, adjusting the current limit for the switch between 0.1A to 1 A. This current limiter offers several operational modes, selectable through a populated jumper labeled as R11 connected to the CLMD pin of the MAX17608. In a default configuration, this pin is connected to the ground, representing the Continuous mode of operation. When R11 is replaced with a 150kΩ resistor, this Click board™ is in the Latch-off mode, and when the user leaves this pin unconnected, Autoretry mode of operation is activated. More information on the operational modes

can be found in the attached datasheet. Current Limit 6 Click can be turned on, or off through the EN pin routed to the PWM pin of the mikroBUS™ socket, hence offering a switch operation to turn ON/OFF power delivery to the connected load. It also provides communication signals routed to the INT and AN pins of the mikroBUS™ socket, alongside its LED indicators, labeled ER1 and ER2, to indicate different operational and fault signals, such as FLAG and UVOV signals. Besides, the MAX17608 also offers internal thermal shutdown protection against excessive power dissipation. This Click board™ can operate with either 3.3V or 5V logic voltage levels selected via the VCC SEL jumper. This way, both 3.3V and 5V capable MCUs can use the communication lines properly. Also, this Click board™ comes equipped with a library containing easy-to-use functions and an example code that can be used as a reference for further development.

Current Limit 6 Click hardware overview image

Features overview

Development board

Nucleo-64 with STM32F446RE MCU offers a cost-effective and adaptable platform for developers to explore new ideas and prototype their designs. This board harnesses the versatility of the STM32 microcontroller, enabling users to select the optimal balance of performance and power consumption for their projects. It accommodates the STM32 microcontroller in the LQFP64 package and includes essential components such as a user LED, which doubles as an ARDUINO® signal, alongside user and reset push-buttons, and a 32.768kHz crystal oscillator for precise timing operations. Designed with expansion and flexibility in mind, the Nucleo-64 board features an ARDUINO® Uno V3 expansion connector and ST morpho extension pin

headers, granting complete access to the STM32's I/Os for comprehensive project integration. Power supply options are adaptable, supporting ST-LINK USB VBUS or external power sources, ensuring adaptability in various development environments. The board also has an on-board ST-LINK debugger/programmer with USB re-enumeration capability, simplifying the programming and debugging process. Moreover, the board is designed to simplify advanced development with its external SMPS for efficient Vcore logic supply, support for USB Device full speed or USB SNK/UFP full speed, and built-in cryptographic features, enhancing both the power efficiency and security of projects. Additional connectivity is

provided through dedicated connectors for external SMPS experimentation, a USB connector for the ST-LINK, and a MIPI® debug connector, expanding the possibilities for hardware interfacing and experimentation. Developers will find extensive support through comprehensive free software libraries and examples, courtesy of the STM32Cube MCU Package. This, combined with compatibility with a wide array of Integrated Development Environments (IDEs), including IAR Embedded Workbench®, MDK-ARM, and STM32CubeIDE, ensures a smooth and efficient development experience, allowing users to fully leverage the capabilities of the Nucleo-64 board in their projects.

Nucleo 64 with STM32F446RE MCU double side image

Microcontroller Overview

MCU Card / MCU

Architecture

ARM Cortex-M4

MCU Memory (KB)

512

Silicon Vendor

STMicroelectronics

Pin count

RAM (Bytes)

131072

You complete me!

Accessories

Click Shield for Nucleo-64 comes equipped with two proprietary mikroBUS™ sockets, allowing all the Click board™ devices to be interfaced with the STM32 Nucleo-64 board with no effort. This way, Mikroe allows its users to add any functionality from our ever-growing range of Click boards™, such as WiFi, GSM, GPS, Bluetooth, ZigBee, environmental sensors, LEDs, speech recognition, motor control, movement sensors, and many more. More than 1537 Click boards™, which can be stacked and integrated, are at your disposal. The STM32 Nucleo-64 boards are based on the microcontrollers in 64-pin packages, a 32-bit MCU with an ARM Cortex M4 processor operating at 84MHz, 512Kb Flash, and 96KB SRAM, divided into two regions where the top section represents the ST-Link/V2 debugger and programmer while the bottom section of the board is an actual development board. These boards are controlled and powered conveniently through a USB connection to program and efficiently debug the Nucleo-64 board out of the box, with an additional USB cable connected to the USB mini port on the board. Most of the STM32 microcontroller pins are brought to the IO pins on the left and right edge of the board, which are then connected to two existing mikroBUS™ sockets. This Click Shield also has several switches that perform functions such as selecting the logic levels of analog signals on mikroBUS™ sockets and selecting logic voltage levels of the mikroBUS™ sockets themselves. Besides, the user is offered the possibility of using any Click board™ with the help of existing bidirectional level-shifting voltage translators, regardless of whether the Click board™ operates at a 3.3V or 5V logic voltage level. Once you connect the STM32 Nucleo-64 board with our Click Shield for Nucleo-64, you can access hundreds of Click boards™, working with 3.3V or 5V logic voltage levels.

Used MCU Pins

mikroBUS™ mapper

UVLO/OVLO Indicator

PC0

RST

SPI Chip Select

PB12

SPI Clock

PB3

SCK

MISO

SPI Data IN

PB5

MOSI

Power Supply

3.3V

Ground

GND

Enable

PC8

PWM

Fault Interrupt

PC14

INT

SCL

SDA

Power Supply

Ground

GND

Take a closer look

Click board™ Schematic

Current Limit 6 Click Schematic schematic

Step by step

Project assembly

Click Shield for Nucleo-64 accessories 1 image hardware assembly

Start by selecting your development board and Click board™. Begin with the Nucleo 64 with STM32F446RE MCU as your development board.

Nucleo 64 with STM32F401RE MCU front image hardware assembly

LTE IoT 5 Click front image hardware assembly

LTE IoT 5 Click complete accessories setup image hardware assembly

Nucleo-64 with STM32XXX MCU Access MB 1 Mini B Conn - upright/background hardware assembly

Clicker 4 for STM32F4 HA MCU Step hardware assembly

Necto No Display image step 8 hardware assembly

Debug Image Necto Step hardware assembly

Track your results in real time

Application Output

This Click board can be interfaced and monitored in two ways:

Application Output - Use the "Application Output" window in Debug mode for real-time data monitoring. Set it up properly by following this tutorial.

UART Terminal - Monitor data via the UART Terminal using a USB to UART converter. For detailed instructions, check out this tutorial.

Software Support

Library Description

This library contains API for Current Limit 6 Click driver.

Key functions:

currentlimit6_set_current_limit - Current Limit 6 set current limit function
currentlimit6_power_mode - Current Limit 6 power mode function
currentlimit6_check_limit_exceeded - Current Limit 6 check limit exceeded function

Open Source

Code example

The complete application code and a ready-to-use project are available through the NECTO Studio Package Manager for direct installation in the NECTO Studio. The application code can also be found on the MIKROE GitHub account.

/*!
 * @file main.c
 * @brief CurrentLimit6 Click example
 *
 * # Description
 * This library contains API for the Current Limit 6 Click driver.
 * This driver provides the functions to set the current limiting conditions 
 * in order to provide the threshold of the fault conditions.
 *
 * The demo application is composed of two sections :
 *
 * ## Application Init
 * Initialization of SPI module and log UART.
 * After driver initialization, default settings turn on the device.
 *
 * ## Application Task
 * This example demonstrates the use of the Current Limit 6 Click board™.
 * Reading user's input from Usart Terminal and using it as an index 
 * for an array of pre-calculated values that define the current limit level.
 * Results are being sent to the Usart Terminal, where you can track their changes.
 *
 * ## Additional Function
 * - static void display_selection ( void )
 *
 * @author Nenad Filipovic
 *
 */

#include "board.h"
#include "log.h"
#include "currentlimit6.h"

static currentlimit6_t currentlimit6;
static log_t logger;
const float limit_value[ 9 ] = { 0.100, 0.200, 0.300, 0.400, 0.500, 0.600, 0.700, 0.800, 0.999 };

static void display_selection ( void ) 
{
    log_printf( &logger, " To select current limit  \r\n" );
    log_printf( &logger, " Send one of the numbers: \r\n" );
    log_printf( &logger, "- - - - - - - - - - - - - \r\n" );
    log_printf( &logger, " '1' - Limited to 100 mA  \r\n" );
    log_printf( &logger, " '2' - Limited to 200 mA  \r\n" );
    log_printf( &logger, " '3' - Limited to 300 mA  \r\n" );
    log_printf( &logger, " '4' - Limited to 400 mA  \r\n" );
    log_printf( &logger, " '5' - Limited to 500 mA  \r\n" );
    log_printf( &logger, " '6' - Limited to 600 mA  \r\n" );
    log_printf( &logger, " '7' - Limited to 700 mA  \r\n" );
    log_printf( &logger, " '8' - Limited to 800 mA  \r\n" );
    log_printf( &logger, " '9' - Limited to 999 mA  \r\n" );
    log_printf( &logger, "--------------------------\r\n" );
}

void application_init ( void )
{
    log_cfg_t log_cfg;  /**< Logger config object. */
    currentlimit6_cfg_t currentlimit6_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.
    currentlimit6_cfg_setup( &currentlimit6_cfg );
    CURRENTLIMIT6_MAP_MIKROBUS( currentlimit6_cfg, MIKROBUS_1 );
    if ( SPI_MASTER_ERROR == currentlimit6_init( &currentlimit6, &currentlimit6_cfg ) )
    {
        log_error( &logger, " Communication init." );
        for ( ; ; );
    }
    
    if ( CURRENTLIMIT6_ERROR == currentlimit6_default_cfg ( &currentlimit6 ) )
    {
        log_error( &logger, " Default configuration." );
        for ( ; ; );
    }
    
    log_info( &logger, " Application Task " );
    log_printf( &logger, "-------------------------\r\n" );
    log_printf( &logger, "  Current Limit 6 Click  \r\n" );
    log_printf( &logger, "-------------------------\r\n" );
    log_printf( &logger, "- - - - - - - - - - - - -\r\n" );
    Delay_ms( 100 );
    
    display_selection( );
    Delay_ms( 100 );
}

void application_task ( void )
{ 
    static char index;
    
    if ( log_read( &logger, &index, 1 ) != CURRENTLIMIT6_ERROR ) 
    {
        if ( ( index >= '1' ) && ( index <= '9' ) ) 
        {
            currentlimit6_set_current_limit ( &currentlimit6, limit_value[ index - 49 ] );
            log_printf( &logger, "  >>> Selected mode %d     \r\n", index - 48 );
            log_printf( &logger, "- - - - - - - - - - - - -\r\n" );
            log_printf( &logger, " Current limit is %.3f A \r\n", limit_value[ index - 49 ] );
            log_printf( &logger, "--------------------------\r\n" );
            Delay_ms( 100 );
        } 
        else 
        { 
            log_printf( &logger, "    Data not in range!    \r\n" );
            log_printf( &logger, "--------------------------\r\n" );
            display_selection( );
            Delay_ms( 100 );
        }
    }
}

void main ( void )
{
    application_init( );

    for ( ; ; )
    {
        application_task( );
    }
}

// ------------------------------------------------------------------------ END