30 min

Master VCT monitoring with LTC2990 and PIC18LF46K42

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VCT Monitor Click with EasyPIC v8

Published Aug 12, 2023

Click board™

VCT Monitor Click

Development board

EasyPIC v8


NECTO Studio



Track real-time temperature, voltage, and current easily for issue detection and operational optimization



Hardware Overview

How does it work?

VCT Monitor Click is based on the LTC2990, a high-performance temperature, voltage, and current monitor with the I2C serial interface from Analog Devices. The LTC2990 can be configured to measure many combinations of internal temperature, remote temperature, remote voltage or current, and internal VCC with single or repeated measurements. It fits in systems needing sub-millivolt voltage resolution, 1% current measurement, and 1°C temperature accuracy or any combination. The input signals are selected with an input MUX, controlled by the control logic

block. The control logic uses the mode bits in the control register to manage the sequence and types of data acquisition. The control logic also controls the variable current sources during remote temperature acquisition. The ADC performs the necessary conversion(s) and supplies the data to the control logic for further processing for temperature measurements or routing to the appropriate data register for voltage and current measurements. Remote measurements are performed on terminals labeled as TEMP and LOAD using multiple ADC conversions and source

currents to compensate for sensor series resistance. The LTC2990 is calibrated to yield the correct temperature for a remote diode with an ideality factor of 1.004. 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.

VCT Monitor Click hardware overview image

Features overview

Development board

EasyPIC v8 is a development board specially designed for the needs of rapid development of embedded applications. It supports many high pin count 8-bit PIC microcontrollers from Microchip, regardless of their number of pins, and a broad set of unique functions, such as the first-ever embedded debugger/programmer. The development board is well organized and designed so that the end-user has all the necessary elements, such as switches, buttons, indicators, connectors, and others, in one place. Thanks to innovative manufacturing technology, EasyPIC v8 provides a fluid and immersive working experience, allowing access anywhere and under any

circumstances at any time. Each part of the EasyPIC v8 development board contains the components necessary for the most efficient operation of the same board. In addition to the advanced integrated CODEGRIP programmer/debugger module, which offers many valuable programming/debugging options and seamless integration with the Mikroe software environment, the board also includes a clean and regulated power supply module for the development board. It can use a wide range of external power sources, including a battery, an external 12V power supply, and a power source via the USB Type-C (USB-C) connector.

Communication options such as USB-UART, USB DEVICE, and CAN are also included, including the well-established mikroBUS™ standard, two display options (graphical and character-based LCD), and several different DIP sockets. These sockets cover a wide range of 8-bit PIC MCUs, from the smallest PIC MCU devices with only eight up to forty pins. EasyPIC v8 is an integral part of the Mikroe ecosystem for rapid development. Natively supported by Mikroe software tools, it covers many aspects of prototyping and development thanks to a considerable number of different Click boards™ (over a thousand boards), the number of which is growing every day.

EasyPIC v8 horizontal image

Microcontroller Overview

MCU Card / MCU




MCU Memory (KB)


Silicon Vendor


Pin count


RAM (Bytes)


Used MCU Pins

mikroBUS™ mapper

Power Supply
I2C Clock
I2C Data
Power Supply

Take a closer look


VCT Monitor Click Schematic schematic

Step by step

Project assembly

EasyPIC v8 front image hardware assembly

Start by selecting your development board and Click board™. Begin with the EasyPIC v8 as your development board.

EasyPIC v8 front image hardware assembly
GNSS2 Click front image hardware assembly
MCU DIP 40 hardware assembly
GNSS2 Click complete accessories setup image hardware assembly
EasyPIC v8 Access DIPMB 1 - upright/background hardware assembly
Necto image step 2 hardware assembly
Necto image step 3 hardware assembly
Necto image step 4 hardware assembly
NECTO Compiler Selection Step Image hardware assembly
NECTO Output Selection Step Image hardware assembly
Necto image step 6 hardware assembly
Necto DIP image step 7 hardware assembly
Necto image step 8 hardware assembly
Necto image step 9 hardware assembly
Necto image step 10 hardware assembly
Necto PreFlash Image hardware assembly

Track your results in real time

Application Output

After pressing the "FLASH" button on the left-side panel, it is necessary to open the UART terminal to display the achieved results. By clicking on the Tools icon in the right-hand panel, multiple different functions are displayed, among which is the UART Terminal. Click on the offered "UART Terminal" icon.

UART Application Output Step 1

Once the UART terminal is opened, the window takes on a new form. At the top of the tab are two buttons, one for adjusting the parameters of the UART terminal and the other for connecting the UART terminal. The tab's lower part is reserved for displaying the achieved results. Before connecting, the terminal has a Disconnected status, indicating that the terminal is not yet active. Before connecting, it is necessary to check the set parameters of the UART terminal. Click on the "OPTIONS" button.

UART Application Output Step 2

In the newly opened UART Terminal Options field, we check if the terminal settings are correct, such as the set port and the Baud rate of UART communication. If the data is not displayed properly, it is possible that the Baud rate value is not set correctly and needs to be adjusted to 115200. If all the parameters are set correctly, click on "CONFIGURE".

UART Application Output Step 3

The next step is to click on the "CONNECT" button, after which the terminal status changes from Disconnected to Connected in green, and the data is displayed in the Received data field.

UART Application Output Step 4

Software Support

Library Description

This library contains API for VCT Monitor Click driver.

Key functions:

  • vctmonitor_get_status - Gets status value

  • vctmonitor_read_temperature - Get temperature function

  • vctmonitor_read_current - Current 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 VCTMonitor Click example
 * # Description
 * This is an example which demonstrates the use of VCT Monitor Click board.
 * The demo application is composed of two sections :
 * ## Application Init
 * Initialization driver enables the USB uart terminal and I2C.  
 * ## Application Task
 * Reads temperature, current value, and differential voltage every 4 seconds.
 * @note
 * The click has been tested using the following:
 *       - Power supply - 4V
 *       - Current (Load) - 0A to 3A
 *       - External MMBT3904 temperature sensor
 * @author Stefan Ilic

#include "board.h"
#include "log.h"
#include "vctmonitor.h"

static vctmonitor_t vctmonitor;
static log_t logger;

void application_init ( void ) {
    log_cfg_t log_cfg;  /**< Logger config object. */
    vctmonitor_cfg_t vctmonitor_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.
    vctmonitor_cfg_setup( &vctmonitor_cfg );
    VCTMONITOR_MAP_MIKROBUS( vctmonitor_cfg, MIKROBUS_1 );
    err_t init_flag = vctmonitor_init( &vctmonitor, &vctmonitor_cfg );
    if ( I2C_MASTER_ERROR == init_flag ) {
        log_error( &logger, " Application Init Error. " );
        log_info( &logger, " Please, run program again... " );

        for ( ; ; );

    log_info( &logger, " Application Task " );

void application_task ( void ) {
    float temperature;
    float voltage;
    float current;

    voltage = vctmonitor_read_voltage_differential( &vctmonitor );
    log_printf( &logger, " Voltage    : %.2f mV \r\n", voltage );

    current = vctmonitor_read_current( &vctmonitor );
    log_printf( &logger, " Current    : %.2f mA \r\n", current );

    temperature = vctmonitor_read_temperature( &vctmonitor );
    log_printf( &logger, " Temperature: %.2f C \r\n", temperature );

    log_printf( &logger, "- - - - - - - - - - - -\r\n" );
    Delay_ms( 4000 );     

void main ( void ) {
    application_init( );

    for ( ; ; ) {
        application_task( );

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

Additional Support