Maintain signal accuracy in noisy industrial environments with FOD4216 and STM32F302VC

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Opto 5 Click with CLICKER 4 for STM32F302VCT6

Published Jul 22, 2025

Click board™

Opto 5 Click

Dev. board

CLICKER 4 for STM32F302VCT6

Compiler

NECTO Studio

MCU

STM32F302VC

Protect your equipment from ground loops and voltage differences, extending the lifespan of your devices

Hardware Overview

How does it work?

Opto 5 Click is based on the FOD4216, a random phase snubberless Triac driver that provides uncomplicated high voltage safety isolation from ON Semiconductor. It utilizes a high-efficiency infrared emitting diode that offers an improved trigger sensitivity coupled to a hybrid random phase triac formed with two inverse parallel SCRs, which creates the triac function capable of driving discrete triacs. It provides electrical isolation between a low-voltage input and a high-voltage output while switching the high-voltage output. The Triac stands for triode for alternating current and is a device that can conduct current in either direction when triggered or turned on by

detecting a light beam on its trigger junction (Gate). The Triac changes from the off-state to the conducting state when a current or current pulse is applied to the control electrode (Gate). Turning on the device can be achieved while synchronizing with the input voltage, whereas turn-off occurs when the current passes through zero following the control signal removal. Opto 5 Click operates only with the PWM signal from the mikroBUS™ socket that drives the cathode of the FOD4216. In applications, when hot-line switching is required, the “hot” side of the line is switched, and the load is connected to the cold or neutral side. In the case of a Standard Triac usage, the user should add a

39Ω resistor and 0.01uF capacitor parallel to triac terminals A1 and A2 used for snubbing the triac. In the case of highly inductive loads where the power factor is lower than 0.5), the value of a resistor should be 360Ω. In the case of use Snubberless Triac usage, there is no need for these components. 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.

Features overview

Development board

Clicker 4 for STM32F3 is a compact development board designed as a complete solution, you can use it to quickly build your own gadgets with unique functionalities. Featuring a STM32F302VCT6, four mikroBUS™ sockets for Click boards™ connectivity, power managment, and more, it represents a perfect solution for the rapid development of many different types of applications. At its core, there is a STM32F302VCT6 MCU, a powerful microcontroller by STMicroelectronics, based on the high-

performance Arm® Cortex®-M4 32-bit processor core operating at up to 168 MHz frequency. It provides sufficient processing power for the most demanding tasks, allowing Clicker 4 to adapt to any specific application requirements. Besides two 1x20 pin headers, four improved mikroBUS™ sockets represent the most distinctive connectivity feature, allowing access to a huge base of Click boards™, growing on a daily basis. Each section of Clicker 4 is clearly marked, offering an intuitive and clean interface. This makes working with the development

board much simpler and thus, faster. The usability of Clicker 4 doesn’t end with its ability to accelerate the prototyping and application development stages: it is designed as a complete solution which can be implemented directly into any project, with no additional hardware modifications required. Four mounting holes [4.2mm/0.165”] at all four corners allow simple installation by using mounting screws. For most applications, a nice stylish casing is all that is needed to turn the Clicker 4 development board into a fully functional, custom design.

CLICKER 4 for STM32F302VCT6 double image

Microcontroller Overview

MCU Card / MCU

Architecture

ARM Cortex-M4

MCU Memory (KB)

256

Silicon Vendor

STMicroelectronics

Pin count

100

RAM (Bytes)

40960

Used MCU Pins

mikroBUS™ mapper

RST

SCK

MISO

MOSI

Power Supply

3.3V

Ground

GND

PWM Signal

PE9

PWM

INT

SCL

SDA

Power Supply

Ground

GND

Take a closer look

Click board™ Schematic

Step by step

Project assembly

PIC32MZ MXS Data Capture Board front image hardware assembly

Start by selecting your development board and Click board™. Begin with the CLICKER 4 for STM32F302VCT6 as your development board.

Thermo 21 Click front image hardware assembly

Thermo 21 Click complete accessories setup image hardware assembly

Board mapper by product6 hardware assembly

PIC32MZ MXS Data Capture Board NECTO MCU Selection Step hardware assembly

Necto No Display image step 8 hardware assembly

Software Support

Library Description

This library contains API for Opto 5 Click driver.

Key functions:

opto5_pin_set - Opto 5 pin setting function
opto5_pin_clear - Opto 5 pin clearing function
opto5_pin_toggle - Opto 5 pin toggling 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 Opto 5 Click Example.
 *
 * # Description
 * This example demonstrates the use of Opto 5 Click board.
 *
 * The demo application is composed of two sections :
 *
 * ## Application Init
 * Initialization of UART LOG and GPIO pin drivers.
 * The output of PWM is set to high so the optocoupler
 * is not triggered by default.
 *
 * ## Application Task
 * The output pin is toggled every 5 seconds. 
 *
 * @author Stefan Nikolic
 *
 */

#include "board.h"
#include "log.h"
#include "opto5.h"

static opto5_t opto5;               /**< Opto 5 Click driver object. */
static log_t logger;                /**< Logger object. */

void application_init ( void ) {
    log_cfg_t log_cfg;              /**< Logger config object. */
    opto5_cfg_t opto5_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.

    opto5_cfg_setup( &opto5_cfg );
    OPTO5_MAP_MIKROBUS( opto5_cfg, MIKROBUS_1 );
    if ( opto5_init( &opto5, &opto5_cfg ) == DIGITAL_OUT_UNSUPPORTED_PIN ) {
        log_error( &logger, " Application Init Error. " );
        log_info( &logger, " Please, run program again... " );

        for ( ; ; );
    }
    Delay_ms ( 100 );
    opto5_default_cfg ( &opto5 );
    log_info( &logger, " Application Task " );
    Delay_ms ( 100 );
}

void application_task ( void ) {
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    log_printf( &logger, " Pin toggling...\r\n" );
    opto5_pin_toggle( &opto5 );
}

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