Beginner
10 min

Provide a stable, reduced voltage from a higher input voltage source using TPS62903 and PIC32MZ2048EFM100

AEC-Q100 qualified synchronous step-down (buck) DC/DC converter

Buck 15 Click with Curiosity PIC32 MZ EF

Published Mar 07, 2024

Click board™

Buck 15 Click

Dev. board

Curiosity PIC32 MZ EF

Compiler

NECTO Studio

MCU

PIC32MZ2048EFM100

Lower and stabilize the voltage for various systems requiring reliable power management, such as ADAS, body electronics, lighting, and infotainment, ensuring they operate smoothly and safely

A

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Hardware Overview

How does it work?

Buck 15 Click is based on the TPS62903, a synchronous step-down DC/DC converter from Texas Instruments, recognized for its high efficiency, compact size, and adaptability. This converter stands out for its rapid transient response and supports a high output voltage accuracy of ±1.5% across the entire operating temperature range. It employs the DCS-control topology to enhance load transient performance, and its broad input voltage range accommodates various power sources, including 12V supply rails, single-cell or multi-cell Li-Ion batteries, and 5V or 3.3V power rails. Notably, the TPS62903 is designed to automatically enter power save mode under light load conditions, ensuring high efficiency and a low quiescent current of 4µA to optimize performance even at minimal loads. Communication with the Buck 15 Click is conducted through a standard 2-wire interface linked to the AD5242, allowing the

host MCU to adjust the output voltage. The device's I2C address is configurable via the ADDR SEL jumper, with a default setting of 0. This Click board™ also features a power-good (PG) pin that indicates when the output voltage falls outside the predetermined window threshold and an EN pin, which serves as a precision regulator-enable input. Besides these pins, the TPS62903 also has a MODE/Smart-CONF pin, allowing for comprehensive customization of operational parameters such as the internal and external divider, switching frequency, output voltage discharge, and the mode of operation between automatic power save and forced PWM. An 11k R11 resistor setting achieves a 1MHz switching frequency, enabled output discharge, and Auto PFM/PWM Mode. The output voltage is adjustable from 0.4V to 5V, supporting currents up to 3A, enabled by an onboard digital potentiometer, the

AD5242. Buck 15 Click also offers versatile power sourcing options, allowing users to choose between internal and external supplies to suit their application needs best. This flexibility is achieved through the VIN SEL jumper, which enables users to select the VCC position for sourcing power internally via the mikroBUS™ power rails or the VEXT position to connect an external power supply. The external power supply can range from 3V to 17V, providing a broad voltage range for various project requirements. 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.

Buck 15 Click hardware overview image

Features overview

Development board

Curiosity PIC32 MZ EF development board is a fully integrated 32-bit development platform featuring the high-performance PIC32MZ EF Series (PIC32MZ2048EFM) that has a 2MB Flash, 512KB RAM, integrated FPU, Crypto accelerator, and excellent connectivity options. It includes an integrated programmer and debugger, requiring no additional hardware. Users can expand

functionality through MIKROE mikroBUS™ Click™ adapter boards, add Ethernet connectivity with the Microchip PHY daughter board, add WiFi connectivity capability using the Microchip expansions boards, and add audio input and output capability with Microchip audio daughter boards. These boards are fully integrated into PIC32’s powerful software framework, MPLAB Harmony,

which provides a flexible and modular interface to application development a rich set of inter-operable software stacks (TCP-IP, USB), and easy-to-use features. The Curiosity PIC32 MZ EF development board offers expansion capabilities making it an excellent choice for a rapid prototyping board in Connectivity, IOT, and general-purpose applications.

Curiosity PIC32MZ EF double side image

Microcontroller Overview

MCU Card / MCU

default

Architecture

PIC32

MCU Memory (KB)

2048

Silicon Vendor

Microchip

Pin count

100

RAM (Bytes)

524288

Used MCU Pins

mikroBUS™ mapper

NC
NC
AN
NC
NC
RST
ID COMM
RPD4
CS
NC
NC
SCK
NC
NC
MISO
NC
NC
MOSI
Power Supply
3.3V
3.3V
Ground
GND
GND
Module Power-Up
RPE8
PWM
Power-Good Indicator
RF13
INT
NC
NC
TX
NC
NC
RX
I2C Clock
RPA14
SCL
I2C Data
RPA15
SDA
Power Supply
5V
5V
Ground
GND
GND
1

Take a closer look

Click board™ Schematic

Buck 15 Click Schematic schematic

Step by step

Project assembly

Curiosity PIC32MZ EF front image hardware assembly

Start by selecting your development board and Click board™. Begin with the Curiosity PIC32 MZ EF as your development board.

Curiosity PIC32MZ EF front image hardware assembly
GNSS2 Click front image hardware assembly
Prog-cut hardware assembly
GNSS2 Click complete accessories setup image hardware assembly
Curiosity PIC32 MZ EF MB 1 Access - 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
Curiosity PIC32 MZ EF 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

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 Buck 15 Click driver.

Key functions:

  • buck15_set_vout - This function sets the voltage output by using an I2C serial interface

  • buck15_set_vset - This function sets the wiper position for the output voltage settings by using an I2C serial interface

  • buck15_enable_device - This function enables the device by setting the EN pin to high logic state

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 Buck 15 Click example
 *
 * # Description
 * This example demonstrates the use of the Buck 15 Click board by changing the output voltage.
 *
 * The demo application is composed of two sections :
 *
 * ## Application Init
 * Initializes the driver and performs the device default configuration.
 *
 * ## Application Task
 * The demo application changes the output voltage and displays the currently set voltage output value.
 * Results are being sent to the UART Terminal, where you can track their changes.
 *
 * @author Nenad Filipovic
 *
 */

#include "board.h"
#include "log.h"
#include "buck15.h"

static buck15_t buck15;
static log_t logger;

// Output voltage data table
static float vout_table[ 22 ] = { BUCK15_VOUT_TABLE };

void application_init ( void ) 
{
    log_cfg_t log_cfg;  /**< Logger config object. */
    buck15_cfg_t buck15_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.
    buck15_cfg_setup( &buck15_cfg );
    BUCK15_MAP_MIKROBUS( buck15_cfg, MIKROBUS_1 );
    if ( I2C_MASTER_ERROR == buck15_init( &buck15, &buck15_cfg ) ) 
    {
        log_error( &logger, " Communication init." );
        for ( ; ; );
    }
    
    if ( BUCK15_ERROR == buck15_default_cfg ( &buck15 ) )
    {
        log_error( &logger, " Default configuration." );
        for ( ; ; );
    }
    
    log_info( &logger, " Application Task " );
    log_printf( &logger, "____________\r\n" );
    Delay_ms( 100 );
}

void application_task ( void ) 
{
    for ( buck15_vout_t vout = BUCK15_VOUT_0V6; vout <= BUCK15_VOUT_5V; vout++ )
    {
        if ( BUCK15_OK == buck15_set_vout( &buck15, vout ) )
        {
            log_printf( &logger, " Vout : %.1f [V]\r\n", vout_table[ vout ] );
            log_printf( &logger, "____________\r\n" );
            Delay_ms( 5000 );
        }
    }
}

int main ( void ) 
{
    application_init( );
    
    for ( ; ; ) 
    {
        application_task( );
    }

    return 0;
}

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

Additional Support

Resources

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