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Opto 5 Click with UNI Clicker

Published Sep 21, 2023

Click board™

Opto 5 Click

Development board

UNI Clicker


NECTO Studio



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.

Opto 5 Click top side image
Opto 5 Click bottom side image

Features overview

Development board

UNI Clicker is a compact development board designed as a complete solution that brings the flexibility of add-on Click boards™ to your favorite microcontroller, making it a perfect starter kit for implementing your ideas. It supports a wide range of microcontrollers, such as different ARM, PIC32, dsPIC, PIC, and AVR from various vendors like Microchip, ST, NXP, and TI (regardless of their number of pins), four mikroBUS™ sockets for Click board™ connectivity, a USB connector, LED indicators, buttons, a debugger/programmer connector, and two 26-pin headers for interfacing with external electronics. Thanks to innovative manufacturing technology, it allows you to build

gadgets with unique functionalities and features quickly. Each part of the UNI Clicker development kit contains the components necessary for the most efficient operation of the same board. In addition to the possibility of choosing the UNI Clicker programming method, using a third-party programmer or CODEGRIP/mikroProg connected to onboard JTAG/SWD header, the UNI Clicker board also includes a clean and regulated power supply module for the development kit. It provides two ways of board-powering; through the USB Type-C (USB-C) connector, where onboard voltage regulators provide the appropriate voltage levels to each component on the board, or using a Li-Po/Li

Ion battery via an onboard battery connector. All communication methods that mikroBUS™ itself supports are on this board (plus USB HOST/DEVICE), including the well-established mikroBUS™ socket, a standardized socket for the MCU card (SiBRAIN standard), and several user-configurable buttons and LED indicators. UNI Clicker is an integral part of the Mikroe ecosystem, allowing you to create a new application in minutes. Natively supported by Mikroe software tools, it covers many aspects of prototyping thanks to a considerable number of different Click boards™ (over a thousand boards), the number of which is growing every day.

UNI clicker double image

Microcontroller Overview

MCU Card / MCU



8th Generation


ARM Cortex-M4

MCU Memory (KB)


Silicon Vendor


Pin count


RAM (Bytes)


Used MCU Pins

mikroBUS™ mapper

Power Supply
PWM Signal
Power Supply

Take a closer look


Opto 5 Click Schematic schematic

Step by step

Project assembly

UNI Clicker front image hardware assembly

Start by selecting your development board and Click board™. Begin with the UNI Clicker as your development board.

UNI Clicker front image hardware assembly
GNSS2 Click front image hardware assembly
SiBRAIN for STM32F745VG front image hardware assembly
Prog-cut hardware assembly
GNSS2 Click complete accessories setup image hardware assembly
UNI Clicker Access MB 1 - upright/background hardware assembly
Necto image step 2 hardware assembly
Necto image step 3 hardware assembly
Necto image step 4 hardware assembly
Necto image step 5 hardware assembly
Necto image step 6 hardware assembly
Necto image step 7 hardware assembly
Necto No Display image step 8 hardware assembly
Necto image step 9 hardware assembly
Necto image step 10 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.

Application Output Step 1

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™.

Application Output Step 3

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.

Application Output Step 4

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

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

 * @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( 5000 );
    log_printf( &logger, " Pin toggling...\r\n" );
    opto5_pin_toggle( &opto5 );

void main ( void ) {
    application_init( );

    for ( ; ; ) {
        application_task( );

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

Additional Support