Achieve versatility in motor control with STSPIN250 and ATmega328P
Unleash the power of brushed DC motor control!
Published Feb 14, 2024
Click board™
STSPIN250 Click
Dev Board
Arduino UNO Rev3
Compiler
NECTO Studio
MCU
ATmega328P
Experience enhanced motor performance with our brushed DC motor driver, optimizing efficiency, reducing wear, and extending the operational lifespan of your motors
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Hardware Overview
How does it work?
STSPIN250 Click is based on the STSPIN250, a low voltage DC brushed motor driver by STMicroelectronics. This device integrates two full-bridge MOSFET channels in a parallel configuration, sustaining up to 2.6A. This IC targets battery-powered applications, featuring optimizations toward lowered power consumption. It has a PWM current controller with a fixed OFF time, during which the current decay sequence is performed. This effectively limits the current through the connected load (motor). The OFF (decay) time is approximately 40 µs on this Click board™. The PWM current controller compares the voltage across the sense resistor (VSENS) and the VREF voltage, which is adjustable on STSPIN250 click. When VSENS exceeds the VREF voltage, the current limiting is triggered, and the OFF timer starts counting. The decay sequence is performed. Knowing the RSENS, it can be easily calculated how much voltage should be applied to the REF pin of the STSPIN250 to limit the current according to ILOAD. For example, if 0.388V is applied at the VREF pin, the current limit will be maxed out to 2.58A. The onboard
potentiometer allows you to adjust the VREF voltage according to needs simply. The connected motor can be controlled by using these pins: PWM, PH, RST, and EN/INT. The PH pin determines the direction of the current. If set to a HIGH logic level, the current will flow in one direction, and vice-versa: when a LOW logic level is applied, the current will reverse its direction. This pin is routed to the AN pin of the mikroBUS™ and labeled as PH. PWM pin can be used to regulate the speed of the rotation. When this pin has a LOW logic level, the current will start circulating through the low-side (LS) MOSFETs and the motor coil. When there is a HIGH logic level on this pin, the current will flow through the load, depending on the logic state of the PH pin. A higher duty cycle percentage will result in higher angular speed. While the current decay sequence is performed, the logic states on the input pins will be disregarded until the decay timer expires. The decay time is fixed to approximately 40 µs on this Click board™. The STBY/RESET (RST) pin of the STSPIN250 is used to set both bridge outputs in HIGH-Z mode, disconnecting the power supply
from the output stage. This pin allows lower average power consumption as no current can flow from the power supply to the motor. This pin is routed to the RST pin of the mikroBUS™. The EN/FAULT (EN) pin has a double purpose: when set to a high logic level, it acts as a chip enable, allowing the device to operate. In the case of a fault condition on the IC, it will be asserted to a LOW logic level, acting as an interrupt pin. A restart attempt will be made after a timeout period defined by the external capacitor and resistor values. This pin is routed to the CS and INT pin of the mikroBUS™, allowing the host MCU to use both functions. These pins are labeled EN and FLT on the Click board™, respectively. The motor power supply can be connected to the input terminal labeled as VIN and should be within the range of 1.8V to 10V. The motor can be connected at the second terminal, between two poles labeled as A+ and A-. The Click board™ requires an external power supply for the motor to work. However, it also requires 3.3V from the mikroBUS™ rail.
Features overview
Development board
Arduino UNO is a versatile microcontroller board built around the ATmega328P chip. It offers extensive connectivity options for various projects, featuring 14 digital input/output pins, six of which are PWM-capable, along with six analog inputs. Its core components include a 16MHz ceramic resonator, a USB connection, a power jack, an
ICSP header, and a reset button, providing everything necessary to power and program the board. The Uno is ready to go, whether connected to a computer via USB or powered by an AC-to-DC adapter or battery. As the first USB Arduino board, it serves as the benchmark for the Arduino platform, with "Uno" symbolizing its status as the
first in a series. This name choice, meaning "one" in Italian, commemorates the launch of Arduino Software (IDE) 1.0. Initially introduced alongside version 1.0 of the Arduino Software (IDE), the Uno has since become the foundational model for subsequent Arduino releases, embodying the platform's evolution.
Microcontroller Overview
MCU Card / MCU
Architecture
AVR
MCU Memory (KB)
32
Silicon Vendor
Microchip
Pin count
28
RAM (Bytes)
2048
You complete me!
Accessories
Click Shield for Arduino UNO has two proprietary mikroBUS™ sockets, allowing all the Click board™ devices to be interfaced with the Arduino UNO board without effort. The Arduino Uno, a microcontroller board based on the ATmega328P, provides an affordable and flexible way for users to try out new concepts and build prototypes with the ATmega328P microcontroller from various combinations of performance, power consumption, and features. The Arduino Uno has 14 digital input/output pins (of which six can be used as PWM outputs), six analog inputs, a 16 MHz ceramic resonator (CSTCE16M0V53-R0), a USB connection, a power jack, an ICSP header, and reset button. Most of the ATmega328P 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 Arduino UNO board with our Click Shield for Arduino UNO, you can access hundreds of Click boards™, working with 3.3V or 5V logic voltage levels.
Used MCU Pins
mikroBUS™ mapper
Take a closer look
Schematic
Step by step
Project assembly
Start by selecting your development board and Click board™. Begin with the Arduino UNO Rev3 as your development board.
Track your results in real time
Application Output via Debug Mode
1. Once the code example is loaded, pressing the "DEBUG" button initiates the build process, programs it on the created setup, and enters Debug mode.
2. After the programming is completed, a header with buttons for various actions within the IDE becomes visible. Clicking the green "PLAY" button starts reading the results achieved with the Click board™. The achieved results are displayed in the Application Output tab.
Software Support
Library Description
This library contains API for STSPIN250 Click driver.
Key functions:
stspin250_set_ph- This function regulates Direction control pin state. It controls direction of the currentstspin250_enable- This function regulates enable pin statestspin250_reset- This function regulates reset 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 Stspin250 Click example
*
* # Description
* This application enables usage of brushed DC motor driver with
* the current limiting and current sensing.
*
* The demo application is composed of two sections :
*
* ## Application Init
* Initialization driver init, PWM init and enable device
*
* ## Application Task
* This is a example which demonstrates the use of Stspin250 Click board.
* Stspin250 Click communicates with register via PWM interface.
* It shows moving in the left direction from slow to fast speed
* and from fast to slow speed.
* Results are being sent to the Usart Terminal where you can track their changes.
*
* @author Nikola Peric
*
*/
// ------------------------------------------------------------------- INCLUDES
#include "board.h"
#include "log.h"
#include "stspin250.h"
// ------------------------------------------------------------------ VARIABLES
static stspin250_t stspin250;
static log_t logger;
uint8_t motor_direction = 1;
// ------------------------------------------------------ APPLICATION FUNCTIONS
void application_init ( void )
{
log_cfg_t log_cfg;
stspin250_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.
stspin250_cfg_setup( &cfg );
STSPIN250_MAP_MIKROBUS( cfg, MIKROBUS_1 );
stspin250_init( &stspin250, &cfg );
stspin250_enable( &stspin250, STSPIN250_DEVICE_ENABLE );
stspin250_set_duty_cycle ( &stspin250, 0.0 );
stspin250_pwm_start( &stspin250 );
log_info( &logger, "---- Application Task ----" );
Delay_ms( 500 );
}
void application_task ( void )
{
static int8_t duty_cnt = 1;
static int8_t duty_inc = 1;
float duty = duty_cnt / 10.0;
if ( motor_direction == 1 )
{
stspin250_set_ph( &stspin250, 1 );
log_printf( &logger, "> CLOCKWISE <\r\n" );
}
else
{
stspin250_set_ph( &stspin250, 0 );
log_printf( &logger, "> COUNTER CLOCKWISE <\r\n" );
}
stspin250_set_duty_cycle ( &stspin250, duty );
log_printf( &logger, "Duty: %d%%\r\n", ( uint16_t )( duty_cnt * 10 ) );
Delay_ms( 500 );
if ( 10 == duty_cnt )
{
duty_inc = -1;
}
else if ( 0 == duty_cnt )
{
duty_inc = 1;
if ( motor_direction == 1 )
{
motor_direction = 0;
}
else if ( motor_direction == 0 )
{
motor_direction = 1;
}
}
duty_cnt += duty_inc;
}
void main ( void )
{
application_init( );
for ( ; ; )
{
application_task( );
}
}
// ------------------------------------------------------------------------ END
