Ensure stable and protected power delivery with HS2950P and PIC18F45K42

Load protection HotSwitch® for various load conditions

Published Dec 27, 2023

Click board™

Current Limit 10 Click

Dev. board

EasyPIC v8

Compiler

NECTO Studio

MCU

PIC18F45K42

Keep your electronic device safe by controlling the amount of electrical current it uses and protecting it from voltage-related issues

Hardware Overview

How does it work?

Current Limit 10 Click is based on the HS2950P, a load protection HotSwitch from Semtech. It utilizes flexible and programmable protection features and can handle multiple fault conditions. During fault conditions, automatic output discharge will be activated, thus protecting the load, and the HS2950P will automatically restart from a fault condition. The under-voltage lockout threshold is set to the default position (2.6V). The overvoltage protection can be externally set over the OVP SEL jumper, choosing between values 5.44V, 12.36V,

and 24.13V. The OVP is set by default to 5.44V. The current limit threshold can be set over the MAX5419, a nonvolatile digital potentiometer from Analog Devices. You can also choose the onboard external resistor for a fixed 0.5A value. The selection can be made over the ILIM SEL jumper. The soft start time is set to 0.32 ms, and the turn-on delay is set to 4 ms. Current Limit 10 Click uses a standard 2-wire I2C interface of the MAX5419 to allow the host MCU to set the limit threshold. The HS2950P will alert the host MCU when the fault

condition occurs over the FLT pin, along with the FLT LED indicator. Finally, you can turn off the current limiter over the enable EN pin. 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.

Current Limit 10 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.

Microcontroller Overview

MCU Card / MCU

Architecture

PIC

MCU Memory (KB)

Silicon Vendor

Microchip

Pin count

RAM (Bytes)

2048

Used MCU Pins

mikroBUS™ mapper

Power Switch Enable

RE1

RST

ID COMM

RE0

SCK

MISO

MOSI

Power Supply

3.3V

Ground

GND

PWM

Fault Output

RB0

INT

I2C Clock

RC3

SCL

I2C Data

RC4

SDA

Power Supply

Ground

GND

Take a closer look

Click board™ Schematic

Current Limit 10 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.

NECTO Output Selection Step Image hardware assembly

In the advanced settings, pay special attention to the Redirect standard output field. By default, it is set to Application output as the method of displaying final results. To show results via a UART terminal, select the “UART” option in that field and click the “SAVE” button. You will be returned to the Compiler field, and now you can move on to the next step by pressing the “NEXT” button.

GNSS2 Click front image hardware assembly

GNSS2 Click complete accessories setup image hardware assembly

EasyPIC v8 Access DIPMB 1 - upright/background hardware assembly

NECTO Compiler Selection Step Image hardware assembly

Necto DIP image step 7 hardware assembly

Track your results in real time

Application Output

1. Application Output - In Debug mode, the 'Application Output' window enables real-time data monitoring, offering direct insight into execution results. Ensure proper data display by configuring the environment correctly using the provided tutorial.

2. UART Terminal - Use the UART Terminal to monitor data transmission via a USB to UART converter, allowing direct communication between the Click board™ and your development system. Configure the baud rate and other serial settings according to your project's requirements to ensure proper functionality. For step-by-step setup instructions, refer to the provided tutorial.

3. Plot Output - The Plot feature offers a powerful way to visualize real-time sensor data, enabling trend analysis, debugging, and comparison of multiple data points. To set it up correctly, follow the provided tutorial, which includes a step-by-step example of using the Plot feature to display Click board™ readings. To use the Plot feature in your code, use the function: plot(*insert_graph_name*, variable_name);. This is a general format, and it is up to the user to replace 'insert_graph_name' with the actual graph name and 'variable_name' with the parameter to be displayed.

Software Support

Library Description

This library contains API for Current Limit 10 Click driver.

Key functions:

currentlimit10_set_limit - This function sets the desired current limit threshold using the I2C serial interface.
currentlimit10_get_fault - This function gets the state of the fault flag to indicate overcurrent, overtemperature, or reverse-voltage conditions.
currentlimit10_enable - This function turns on the power switch and enables the internal MOSFET.

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 Current Limit 10 Click example
 *
 * # Description
 * This library contains API for the Current Limit 10 Click driver for the current limiting 
 * to a certain value and displays the sources a current proportional to the load current [A].
 *
 * The demo application is composed of two sections :
 *
 * ## Application Init
 * Initialization of I2C module and log UART.
 * After driver initialization, the app executes a default configuration.
 *
 * ## Application Task
 * This example demonstrates the use of the Current Limit 10 Click board. 
 * The demo application sets the current limit threshold of 750 mA and 
 * checks the fault flag for overcurrent conditions.
 *
 * @author Nenad Filipovic
 *
 */

#include "board.h"
#include "log.h"
#include "currentlimit10.h"

static currentlimit10_t currentlimit10;
static log_t logger;

void application_init ( void ) 
{
    log_cfg_t log_cfg;  /**< Logger config object. */
    currentlimit10_cfg_t currentlimit10_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.
    currentlimit10_cfg_setup( &currentlimit10_cfg );
    CURRENTLIMIT10_MAP_MIKROBUS( currentlimit10_cfg, MIKROBUS_1 );
    if ( I2C_MASTER_ERROR == currentlimit10_init( &currentlimit10, &currentlimit10_cfg ) ) 
    {
        log_error( &logger, " Communication init." );
        for ( ; ; );
    }
    
    if ( CURRENTLIMIT10_ERROR == currentlimit10_default_cfg ( &currentlimit10 ) )
    {
        log_error( &logger, " Default configuration." );
        for ( ; ; );
    }
    
    log_info( &logger, " Application Task " );
    Delay_ms( 100 );
}

void application_task ( void ) 
{
    if ( CURRENTLIMIT10_OK == currentlimit10_set_limit( &currentlimit10, 0.75 ) )
    {
        Delay_ms( 100 );
        if ( CURRENTLIMIT10_FAULT_FLAG == currentlimit10_get_fault( &currentlimit10 ) )
        {
            log_printf( &logger, "Fault flag: Overcurrent\r\n" );
            Delay_ms( 100 );
        }
        else
        {
            log_printf( &logger, " Current limit is 0.75 A\r\n" );
            Delay_ms( 100 );
        }
    }
    Delay_ms( 1000 );
}

void main ( void ) 
{
    application_init( );

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

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