Achieve exceptional results with DRV887N and PIC18F46K20

Mastering the art of brushed motor control

Published Nov 01, 2023

Click board™

H-Bridge 7 Click

Dev Board

Curiosity HPC

Compiler

NECTO Studio

MCU

PIC18F46K20

Experience the seamless integration of brushed motor control and save your battery life by using this solution that supports a wide range of output load currents for various motors and loads

Hardware Overview

How does it work?

H-Bridge 7 Click is based on the DRV8876N, N-channel H-bridge motor driver from Texas Instruments that operates from a supply voltage of 4.5V to 37V, supporting a wide range of output load currents for various types of motors and loads. This device integrates an H-bridge output power stage that can be operated in control modes set by the PMODE pin setting. The device also integrates a charge pump regulator to support more efficient high-side N-channel MOSFETs and 100% duty cycle operation. The device operates from a single power supply input (VM) which can be directly connected to a battery or DC voltage supply. The nSLEEP pin (nSL pin on the mikroBUS™) provides an ultra-low power mode to minimize current draw during system inactivity.

Also, this device is fully protected against supply undervoltage, charge pump undervoltage, output overcurrent, and device overtemperature events. H-Bridge 7 Click supports different control schemes with the EN/IN1 and PH/IN2 pins. The control mode is selected through the PMODE pin with either logic low, logic high, or setting the pin Hi-Z (in this case, PMODE is on the logic low level, which means that the device is latched into PH/EN mode). PH/EN mode allows for the H-bridge to be controlled with a speed and direction type of interface. In this configuration, Click board™ drives a bidirectional current through an external load (such as a brushed DC motor), and the H-bridge polarity and duty cycle are controlled with a PWM and IO resource from the external controller

to the EN/IN1 and PH/IN2 pins. The device is then configured for the PH/EN control mode by tying the PMODE pin to GND. Some applications of DRV8876N include brushed DC motors, solenoids, and actuators, but they also can be utilized to drive many common passive loads such as LEDs, resistive elements, relays, and more. 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. However, the 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.

H-Bridge 7 Click hardware overview image

Features overview

Development board

Curiosity HPC, standing for Curiosity High Pin Count (HPC) development board, supports 28- and 40-pin 8-bit PIC MCUs specially designed by Microchip for the needs of rapid development of embedded applications. This board has two unique PDIP sockets, surrounded by dual-row expansion headers, allowing connectivity to all pins on the populated PIC MCUs. It also contains a powerful onboard PICkit™ (PKOB), eliminating the need for an external programming/debugging tool, two mikroBUS™ sockets for Click board™ connectivity, a USB connector, a set of indicator LEDs, push button switches and a variable potentiometer. All

these features allow you to combine the strength of Microchip and Mikroe and create custom electronic solutions more efficiently than ever. Each part of the Curiosity HPC development board contains the components necessary for the most efficient operation of the same board. An integrated onboard PICkit™ (PKOB) allows low-voltage programming and in-circuit debugging for all supported devices. When used with the MPLAB® X Integrated Development Environment (IDE, version 3.0 or higher) or MPLAB® Xpress IDE, in-circuit debugging allows users to run, modify, and troubleshoot their custom software and hardware

quickly without the need for additional debugging tools. Besides, it includes a clean and regulated power supply block for the development board via the USB Micro-B connector, alongside all communication methods that mikroBUS™ itself supports. Curiosity HPC development board allows you to create a new application in just a few steps. Natively supported by Microchip software tools, it covers many aspects of prototyping thanks to many number of different Click boards™ (over a thousand boards), the number of which is growing daily.

Microcontroller Overview

MCU Card / MCU

Architecture

PIC

MCU Memory (KB)

Silicon Vendor

Microchip

Pin count

RAM (Bytes)

3936

You complete me!

Accessories

DC Gear Motor - 430RPM (3-6V) represents an all-in-one combination of a motor and gearbox, where the addition of gear leads to a reduction of motor speed while increasing the torque output. This gear motor has a spur gearbox, making it a highly reliable solution for applications with lower torque and speed requirements. The most critical parameters for gear motors are speed, torque, and efficiency, which are, in this case, 520RPM with no load and 430RPM at maximum efficiency, alongside a current of 60mA and a torque of 50g.cm. Rated for a 3-6V operational voltage range and clockwise/counterclockwise rotation direction, this motor represents an excellent solution for many functions initially performed by brushed DC motors in robotics, medical equipment, electric door locks, and much more.

Used MCU Pins

mikroBUS™ mapper

H-Bridge Control 1

RD0

RST

Sleep Mode

RA3

SCK

MISO

MOSI

Power Supply

3.3V

Ground

GND

H-Bridge Control 2

RC2

PWM

Fault Indicator

RB5

INT

SCL

SDA

Power Supply

Ground

GND

Take a closer look

Schematic

Step by step

Project assembly

Curiosity HPC front no-mcu image hardware assembly

Start by selecting your development board and Click board™. Begin with the Curiosity HPC as your development board.

GNSS2 Click front image hardware assembly

GNSS2 Click complete accessories setup image hardware assembly

Curiosity HPC Access MB 1 - upright/background hardware assembly

Necto DIP image step 7 hardware assembly

Necto No Display image step 8 hardware assembly

Debug Image Necto Step hardware assembly

Track your results in real time

Application Output

After loading the code example, pressing the "DEBUG" button builds and programs it on the selected setup.

After programming is completed, a header with buttons for various actions available in the IDE appears. By clicking the green "PLAY "button, we start reading the results achieved with Click board™.

Upon completion of programming, the Application Output tab is automatically opened, where the achieved result can be read. In case of an inability to perform the Debug function, check if a proper connection between the MCU used by the setup and the CODEGRIP programmer has been established. A detailed explanation of the CODEGRIP-board connection can be found in the CODEGRIP User Manual. Please find it in the RESOURCES section.

Software Support

Library Description

This library contains API for H-Bridge 7 Click driver.

Key functions:

void hbridge7_motor_state ( uint8_t state ) Set motor state
void hbridge7_motor_control ( uint8_t ctrl ) Set motor control
uint8_t hbridge7_get_fault_state ( void ) Get Fault pin state

Open Source

Code example

This example can be found in NECTO Studio. Feel free to download the code, or you can copy the code below.

/*!
 * \file 
 * \brief H-BRIDGE 7 Click example
 * 
 * # Description
 * This example demonstrates the use of H-Bridge 7 click board. 
 *
 * The demo application is composed of two sections :
 * 
 * ## Application Init 
 * Initializes the driver and makes an initial log.
 * 
 * ## Application Task  
 * Drives the motor in the forward direction for 5 seconds, then pulls brake for 2 seconds, 
 * and after that drives it in the reverse direction for 5 seconds, and finally, 
 * disconnects the motor for 2 seconds. Each step will be logged on the USB UART where
 * you can track the program flow.
 * 
 * \author MikroE Team
 *
 */
// ------------------------------------------------------------------- INCLUDES

#include "board.h"
#include "log.h"
#include "hbridge7.h"

// ------------------------------------------------------------------ VARIABLES

static hbridge7_t hbridge7;
static log_t logger;

// ------------------------------------------------------ APPLICATION FUNCTIONS

void application_init ( void )
{
    log_cfg_t log_cfg;
    hbridge7_cfg_t cfg;

    /** 
     * 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.

    hbridge7_cfg_setup( &cfg );
    HBRIDGE7_MAP_MIKROBUS( cfg, MIKROBUS_1 );
    hbridge7_init( &hbridge7, &cfg );
}

void application_task ( void )
{
    log_printf( &logger, "The motor turns forward! \r\n" );
    hbridge7_motor_control( &hbridge7, HBRIDGE7_MOTOR_FORWARD );
    Delay_ms( 5000 );
    
    log_printf( &logger, "Pull brake! \r\n" );
    hbridge7_motor_control( &hbridge7, HBRIDGE7_MOTOR_BRAKE );
    Delay_ms( 2000 );

    log_printf( &logger, "The motor turns in reverse! \r\n" );
    hbridge7_motor_control( &hbridge7, HBRIDGE7_MOTOR_REVERSE );
    Delay_ms( 5000 );

    log_printf( &logger, "The motor is disconnected (High-Z)!  \r\n" );
    hbridge7_motor_control( &hbridge7, HBRIDGE7_MOTOR_SLEEP );
    Delay_ms( 2000 );
}

void main ( void )
{
    application_init( );

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

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