Beginner
10 min

Achieve electrical isolation in various high-voltage applications with VO2630 and ATmega328P

No shocks, all safety!

OPTO Click with Arduino UNO Rev3

Published Feb 14, 2024

Click board™

OPTO Click

Dev Board

Arduino UNO Rev3

Compiler

NECTO Studio

MCU

ATmega328P

Provide electrical isolation from high voltage between input and output circuits in various applications, particularly where high-speed data transfer and a wide temperature range are important considerations

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Hardware Overview

How does it work?

Opto Click is based on a double pack of the DIP socket VO2630, dual-channel, high-speed optocoupler modules from Vishay Semiconductors, providing electrical isolation between the input and output source. The VO2630 enables a high speed of 10Mbit/s data transfer between its input and output with galvanic isolation utilizing a highly efficient input LED coupled with an integrated optical photodiode detector. The detector has an open drain NMOS-transistor output, providing less

leakage than an open collector Schottky clamped transistor output. The VO2630 works like a switch connecting two isolated circuits, so when the current stops flowing through the LED, the photosensitive device stops conducting and turns off. It guarantees AC and DC performance withstanding 5300Vrms of isolation voltage over a wide temperature range from -40°C to +100°C. The outputs of the optocouplers are connected to four pins of the mikroBUS™ labeled IN1-IN4 and routed

to the INT, CS, RST, and AN pins of the mikroBUS™ socket. This Click board™ can operate with either 3.3V or 5V logic voltage levels selected via the I/O Level 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 Click hardware overview image

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.

Arduino UNO Rev3 double side image

Microcontroller Overview

MCU Card / MCU

default

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.

Click Shield for Arduino UNO accessories 1 image

Used MCU Pins

mikroBUS™ mapper

Optocoupler Output 4
PC0
AN
Optocoupler Output 3
PD2
RST
Optocoupler Output 2
PB2
CS
NC
NC
SCK
NC
NC
MISO
NC
NC
MOSI
Power Supply
3.3V
3.3V
Ground
GND
GND
NC
NC
PWM
Optocoupler Output 1
PC3
INT
NC
NC
TX
NC
NC
RX
NC
NC
SCL
NC
NC
SDA
Power Supply
5V
5V
Ground
GND
GND
1

Take a closer look

Schematic

OPTO Click Schematic schematic

Step by step

Project assembly

Click Shield for Arduino UNO front image hardware assembly

Start by selecting your development board and Click board™. Begin with the Arduino UNO Rev3 as your development board.

Click Shield for Arduino UNO front image hardware assembly
Arduino UNO Rev3 front image hardware assembly
Charger 27 Click front image hardware assembly
Prog-cut hardware assembly
Charger 27 Click complete accessories setup image hardware assembly
Arduino UNO Rev3 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
Arduino UNO MCU Step 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 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.

DEBUG_Application_Output

Software Support

Library Description

This library contains API for OPTO Click driver. 

Key functions:

  • opto_check_out1 - This function checks the state of OUT1 pin

  • opto_check_out2 - This function checks the state of OUT2 pin

  • opto_check_out3 - This function checks the state of OUT3 pin

  • opto_check_out4 - This function checks the state of OUT4 pin

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 OPTO Click example
 * 
 * # Description
 * This application checks the state of selected inputs and prints it.
 *
 * The demo application is composed of two sections :
 * 
 * ## Application Init 
 * Initialization driver enables GPIO and also starts write log.
 * 
 * ## Application Task  
 * This example demonstrates the use of OPTO Click board by performing
 * the check procedure for selected outputs and displays the results on USART terminal.
 * 
 * 
 * \author MikroE Team
 *
 */
// ------------------------------------------------------------------- INCLUDES

#include "board.h"
#include "log.h"
#include "opto.h"

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

static opto_t opto;
static log_t logger;
uint8_t sel_output;
uint8_t check_output;
uint8_t cnt;
uint8_t tmp;
// ------------------------------------------------------- ADDITIONAL FUNCTIONS

void opto_set_logger( uint8_t sel_out1, uint8_t sel_out2, uint8_t sel_out3, uint8_t sel_out4 )
{
    if ( sel_out1 > 1 )
    {
        sel_out1 = 1;
    }
    if ( sel_out2 > 1 )
    {
        sel_out2 = 1;
    }
    if ( sel_out3 > 1 )
    {
        sel_out3 = 1;
    }
    if ( sel_out4 > 1 )
    {
        sel_out4 = 1;
    }

    sel_output = 0;
    sel_output |= sel_out1;
    sel_output |= sel_out2 << 1;
    sel_output |= sel_out3 << 2;
    sel_output |= sel_out4 << 3;
}

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

void application_init ( void )
{
    log_cfg_t log_cfg;
    opto_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.

    opto_cfg_setup( &cfg );
    OPTO_MAP_MIKROBUS( cfg, MIKROBUS_1 );
    opto_init( &opto, &cfg );
    opto_set_logger(1,1,1,1);
}

void application_task ( void )
{
    tmp = 1;

    for( cnt = 0; cnt < 4; cnt++ )
    {
        switch( sel_output & tmp )
        {
            case 0x01 :
            {
                check_output = opto_check_out1( &opto );

                if( check_output == 0 )
                {
                    log_printf( &logger, "OUT1 is low\r\n" );
                }
                else
                {
                    log_printf( &logger, "OUT1 is high\r\n" );
                }
            break;
            }
            case 0x02 :
            {
                check_output = opto_check_out2( &opto );

                if ( check_output == 0 )
                {
                    log_printf( &logger, "OUT2 is low\r\n" );
                }
                else
                {
                    log_printf( &logger, "OUT2 is high\r\n" );
                }
            break;
            }
            case 0x04 :
            {
                check_output = opto_check_out3( &opto );

                if ( check_output == 0 )
                {
                    log_printf( &logger, "OUT3 is low\r\n" );
                }
                else
                {
                    log_printf( &logger, "OUT3 is high\r\n" );
                }
            break;
            }
            case 0x08 :
            {
                check_output = opto_check_out4( &opto );

                if ( check_output == 0 )
                {
                    log_printf( &logger, "OUT4 is low\r\n" );
                }
                else
                {
                    log_printf( &logger, "OUT4 is high\r\n" );
                }
            break;
            }
            default :
            {
            break;
            }
        }

        tmp <<= 1;
    }
    Delay_ms( 2000 );
}

void main ( void )
{
    application_init( );

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


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

Additional Support

Resources

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