Beginner
10 min

Ensure stable and protected power delivery with HS2950P and PIC18F47K40

Load protection HotSwitch® for various load conditions

Current Limit 10 Click with Curiosity HPC

Published Dec 27, 2023

Click board™

Current Limit 10 Click

Dev Board

Curiosity HPC

Compiler

NECTO Studio

MCU

PIC18F47K40

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

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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

Curiosity HPC, standing for Curiosity High Pin Count (HPC) development board, supports 28- and 40-pin 8-bit PIC MCUs specially designed by Microchip for the needs of rapid development of embedded applications. This board has two unique PDIP sockets, surrounded by dual-row expansion headers, allowing connectivity to all pins on the populated PIC MCUs. It also contains a powerful onboard PICkit™ (PKOB), eliminating the need for an external programming/debugging tool, two mikroBUS™ sockets for Click board™ connectivity, a USB connector, a set of indicator LEDs, push button switches and a variable potentiometer. All

these features allow you to combine the strength of Microchip and Mikroe and create custom electronic solutions more efficiently than ever. Each part of the Curiosity HPC development board contains the components necessary for the most efficient operation of the same board. An integrated onboard PICkit™ (PKOB) allows low-voltage programming and in-circuit debugging for all supported devices. When used with the MPLAB® X Integrated Development Environment (IDE, version 3.0 or higher) or MPLAB® Xpress IDE, in-circuit debugging allows users to run, modify, and troubleshoot their custom software and hardware

quickly without the need for additional debugging tools. Besides, it includes a clean and regulated power supply block for the development board via the USB Micro-B connector, alongside all communication methods that mikroBUS™ itself supports. Curiosity HPC development board allows you to create a new application in just a few steps. Natively supported by Microchip software tools, it covers many aspects of prototyping thanks to many number of different Click boards™ (over a thousand boards), the number of which is growing daily.

Curiosity HPC double image

Microcontroller Overview

MCU Card / MCU

PIC18F47K40

Architecture

PIC

MCU Memory (KB)

128

Silicon Vendor

Microchip

Pin count

40

RAM (Bytes)

3728

Used MCU Pins

mikroBUS™ mapper

NC
NC
AN
Power Switch Enable
RD0
RST
ID COMM
RA3
CS
NC
NC
SCK
NC
NC
MISO
NC
NC
MOSI
Power Supply
3.3V
3.3V
Ground
GND
GND
NC
NC
PWM
Fault Output
RB5
INT
NC
NC
TX
NC
NC
RX
I2C Clock
RC3
SCL
I2C Data
RC4
SDA
Power Supply
5V
5V
Ground
GND
GND
1

Take a closer look

Schematic

Current Limit 10 Click Schematic schematic

Step by step

Project assembly

Curiosity HPC front no-mcu image hardware assembly

Start by selecting your development board and Click board™. Begin with the Curiosity HPC as your development board.

Curiosity HPC front no-mcu image hardware assembly
GNSS2 Click front image hardware assembly
MCU DIP 40 hardware assembly
Prog-cut hardware assembly
GNSS2 Click complete accessories setup image hardware assembly
Curiosity HPC 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 DIP 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 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

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 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

Additional Support

Resources