Create innovative BLDC motor control with LB11685AV and PIC18F4682

Unleash smooth and powerful motion

Published Nov 01, 2023

Click board™

Brushless 16 Click

Dev. board

EasyPIC v8

Compiler

NECTO Studio

MCU

PIC18F4682

Our cutting-edge solution efficiently drives cooling fan motors, ensuring optimal airflow and temperature regulation for a refreshing and quiet environment

Hardware Overview

How does it work?

Brushless 16 Click is based on the LB11685AV, a three-phase full-wave current-linear-drive motor driver from ON Semiconductor. The LB11685AV adopts a sensorless control system without using a Hall-effect device. It features a current soft switching circuit for silent operation. It is also characterized by easy control, current limit, and various protection features. This Click board™ makes the perfect solution for delivering quiet, cool operation to home appliances and office automation equipment. Start-Up Mode is set when the LB11685AV starts its operation. After the "START" position, the LB11685AV outputs energization timing patterns for a Start-Up in each output (U/V/W) to determine the position of a motor. Based on the timing pattern, the motor starts rotation, and LB11685AV detects back-EMF, defining a motor position. As a result, the

LB11685AV outputs energization timing, which synchronizes with the motor position to the motor. That's how a motor starts rotation. When the LB11685AV switches from Start-Up Mode to Regular rotation Mode, the driving current is switched to full driving mode, which increases the rotation speed until it is stabilized. Brushless 12 Click communicates with MCU using several GPIO pins. The device can be turned on or off through a dedicated Enable (EN) pin routed on the CS pin of the mikroBUS™ socket, while the FG pin routed on the PWM pin serves as a rotation speed indicator and outputs a rectangular waveform in reverse to V motor signal made by back EMF. Besides, it is possible to detect motor lock events on the interrupt RD pin routed to the INT signal of the mikroBUS™ socket, where the indication of such a condition is performed using the red LED

indicator labeled as MOTOR LOCK. Brushless 16 Click supports an external power supply connected to the input terminal labeled as VM, next to the U, V, W, and COM terminals on which the BLDC motor needs to be connected. The absolute maximum rating of the power supply voltage is 19V which must not be exceeded, even for a moment. Do not exceed any of these ratings! This Click board™ can operate with both 3.3V and 5V logic voltage levels selected via the VCC SEL jumper. It allows both 3.3V and 5V capable MCUs to use the communication lines properly. Additionally, there is a possibility for LB11685AV power supply selection via jumper labeled as VFAN SEL to supply the LB11685AV from an external input terminal in the range from 4.5 to 19V or with a 5V from mikroBUS™ power rail.

Brushless 16 Click hardware overview image

Features overview

Development board

EasyPIC v8 is a development board specially designed for the needs of rapid development of embedded applications. It supports many high pin count 8-bit PIC microcontrollers from Microchip, regardless of their number of pins, and a broad set of unique functions, such as the first-ever embedded debugger/programmer. The development board is well organized and designed so that the end-user has all the necessary elements, such as switches, buttons, indicators, connectors, and others, in one place. Thanks to innovative manufacturing technology, EasyPIC v8 provides a fluid and immersive working experience, allowing access anywhere and under any

circumstances at any time. Each part of the EasyPIC v8 development board contains the components necessary for the most efficient operation of the same board. In addition to the advanced integrated CODEGRIP programmer/debugger module, which offers many valuable programming/debugging options and seamless integration with the Mikroe software environment, the board also includes a clean and regulated power supply module for the development board. It can use a wide range of external power sources, including a battery, an external 12V power supply, and a power source via the USB Type-C (USB-C) connector.

Communication options such as USB-UART, USB DEVICE, and CAN are also included, including the well-established mikroBUS™ standard, two display options (graphical and character-based LCD), and several different DIP sockets. These sockets cover a wide range of 8-bit PIC MCUs, from the smallest PIC MCU devices with only eight up to forty pins. EasyPIC v8 is an integral part of the Mikroe ecosystem for rapid development. Natively supported by Mikroe software tools, it covers many aspects of prototyping and development thanks to a considerable number of different Click boards™ (over a thousand boards), the number of which is growing every day.

Microcontroller Overview

MCU Card / MCU

Architecture

PIC

MCU Memory (KB)

Silicon Vendor

Microchip

Pin count

RAM (Bytes)

3328

You complete me!

Accessories

2207V-2500kV BLDC Motor is an outrunner brushless DC motor with a kV rating of 2500 and an M5 shaft diameter. It is an excellent solution for fulfilling many functions initially performed by brushed DC motors or in RC drones, racing cars, and much more.

Used MCU Pins

mikroBUS™ mapper

RST

Enable

RE0

SCK

MISO

MOSI

Power Supply

3.3V

Ground

GND

Rotation Speed Indication

RC0

PWM

Motor Lock Detection

RB0

INT

SCL

SDA

Power Supply

Ground

GND

Take a closer look

Click board™ Schematic

Step by step

Project assembly

EasyPIC v8 front image hardware assembly

Start by selecting your development board and Click board™. Begin with the EasyPIC v8 as your development board.

NECTO Output Selection Step Image hardware assembly

In the advanced settings, pay special attention to the Redirect standard output field. By default, it is set to Application output as the method of displaying final results. To show results via a UART terminal, select the “UART” option in that field and click the “SAVE” button. You will be returned to the Compiler field, and now you can move on to the next step by pressing the “NEXT” button.

GNSS2 Click front image hardware assembly

GNSS2 Click complete accessories setup image hardware assembly

EasyPIC v8 Access DIPMB 1 - upright/background hardware assembly

NECTO Compiler Selection Step Image hardware assembly

Necto DIP image step 7 hardware assembly

Software Support

Library Description

This library contains API for Brushless 16 Click driver.

Key functions:

brushless16_set_en - This function set en pin state
brushless16_get_rd - This function get rd pin state
brushless16_get_fg - This function get fg pin state

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 Brushless 16 Click Example.
 *
 * # Description
 * This example showcases ability to enable and disable motor output,
 * and check the status pins.
 *
 * The demo application is composed of two sections :
 *
 * ## Application Init
 * Initializon of UART module for log and pins for motor control.
 *
 * ## Application Task
 * Checks state of information pins every ms, and stop and start motor
 * output every second.
 *
 * @author Luka Filipovic
 *
 */

#include "board.h"
#include "log.h"
#include "brushless16.h"

static brushless16_t brushless16;   /**< Brushless 16 Click driver object. */
static log_t logger;    /**< Logger object. */

void application_init ( void ) 
{
    log_cfg_t log_cfg;  /**< Logger config object. */
    brushless16_cfg_t brushless16_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.
    brushless16_cfg_setup( &brushless16_cfg );
    BRUSHLESS16_MAP_MIKROBUS( brushless16_cfg, MIKROBUS_1 );
    if ( brushless16_init( &brushless16, &brushless16_cfg ) == DIGITAL_OUT_UNSUPPORTED_PIN ) 
    {
        log_error( &logger, " Application Init Error. " );
        log_info( &logger, " Please, run program again... " );

        for ( ; ; );
    }
    Delay_ms ( 500 );
    log_info( &logger, " Application Task " );
}

void application_task ( void ) 
{
    static uint16_t timer = 5000;
    static uint8_t state = 1;
    
    if ( brushless16_get_rd( &brushless16 ) )
    {
        log_info( &logger, " Motor Lock" );
        Delay_ms ( 500 );
    }
    
    if ( brushless16_get_fg( &brushless16 ) )
    {
        log_info( &logger, " FG" );
        Delay_ms ( 500 );
    }
    
    if ( !( timer-- ) )
    {
        timer = 5000;
        
        if ( state )
        {
            log_info( &logger, " Motor stop" );
        }
        else
        {
            log_info( &logger, " Motor rotating" );
        }
        
        brushless16_set_en( &brushless16, state );
        state = !state;
    }
    
    Delay_ms ( 1 );
}

int main ( void ) 
{
    /* Do not remove this line or clock might not be set correctly. */
    #ifdef PREINIT_SUPPORTED
    preinit();
    #endif
    
    application_init( );
    
    for ( ; ; ) 
    {
        application_task( );
    }

    return 0;
}

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