Beginner
10 min
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Convert higher input voltages into lower, more usable voltage levels with TPSM82913 and PIC18LF45K50

Ensure that your projects get the right amount of power

Step Down 11 Click with EasyPIC v8

Published Dec 28, 2023

Click board™

Step Down 11 Click

Development board

EasyPIC v8

Compiler

NECTO Studio

MCU

PIC18LF45K50

Transform higher input voltages into adjustable lower outputs, ensuring compatibility with diverse scenarios that demand precise voltage regulation, low-ripple, and low-noise operation

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Hardware Overview

How does it work?

Step Down 11 Click is based on the TPSM82913, a low-noise and low-ripple buck power module from Texas Instruments. The devices operate at a fixed switching frequency of 2.2MHz or 1MHz, which depends on the smart configuration input of the buck module. The AD5142A, a dual-channel 256-position nonvolatile digital potentiometer, controls the smart configuration input. By controlling the smart configuration input, you enable or disable spread spectrum modulation. DC/DC converters generate an output voltage ripple at the switching

frequency. The AD5142A also controls the feedback input of the buck module with its other wiper. In addition, the Step Down 11 Click features a soft start, high output accuracy, power-good output, and more. Step Down 11 Click uses a standard 2-wire interface of the AD5142A to allow the host MCU to set the output voltage, supporting 3MHz bandwidth. You can reset the digital potentiometer over the RST pin in case of need. The I2C address can be selected over the ADDR SEL jumpers (0 set by default). The power-good PG pin will be asserted if

the output voltage is not within the specified window threshold. The EN pin is a precision enable input to the regulator. 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.

Step Down 11 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

PIC18LF45K50

Architecture

PIC

MCU Memory (KB)

32

Silicon Vendor

Microchip

Pin count

40

RAM (Bytes)

2048

Used MCU Pins

mikroBUS™ mapper

NC
NC
AN
Reset
RE1
RST
ID COMM
RE0
CS
NC
NC
SCK
NC
NC
MISO
NC
NC
MOSI
Power Supply
3.3V
3.3V
Ground
GND
GND
Enable
RC0
PWM
Power Good Output
RB0
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

Step Down 11 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 Step Down 11 Click driver.

Key functions:

  • stepdown11_get_resistance - Step Down 11 get the resistance function.

  • stepdown11_set_voltage - Step Down 11 set voltage output function.

  • stepdown11_set_mode - Step Down 11 set S-CONF device configuration mode 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 Step Down 11 Click example
 *
 * # Description
 * This library contains API for the Step Down 11 Click driver.
 * This driver provides the functions to set the output voltage treshold.
 *
 * The demo application is composed of two sections :
 *
 * ## Application Init
 * Initialization of I2C module and log UART.
 * After driver initialization, default settings sets output voltage to 1 V.
 *
 * ## Application Task
 * This example demonstrates the use of the Step Down 11 Click board™ by changing 
 * output voltage every 5 seconds starting from 1 V up to 5 V.
 *
 * @author Stefan Ilic
 *
 */

#include "board.h"
#include "log.h"
#include "stepdown11.h"

static stepdown11_t stepdown11;
static log_t logger;

void application_init ( void ) 
{
    log_cfg_t log_cfg;  /**< Logger config object. */
    stepdown11_cfg_t stepdown11_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.
    stepdown11_cfg_setup( &stepdown11_cfg );
    STEPDOWN11_MAP_MIKROBUS( stepdown11_cfg, MIKROBUS_1 );
    if ( I2C_MASTER_ERROR == stepdown11_init( &stepdown11, &stepdown11_cfg ) ) 
    {
        log_error( &logger, " Communication init." );
        for ( ; ; );
    }
    
    if ( STEPDOWN11_ERROR == stepdown11_default_cfg ( &stepdown11 ) )
    {
        log_error( &logger, " Default configuration." );
        for ( ; ; );
    }
    
    log_info( &logger, " Application Task " );
}

void application_task ( void ) 
{
    for ( uint8_t vout = 1; vout <= 5; vout++ )
    {
        log_printf( &logger, " Set output voltage %dV \r\n", ( uint16_t ) vout );
        stepdown11_set_voltage ( &stepdown11, vout );
        Delay_ms( 5000 );
    }
}

void main ( void ) 
{
    application_init( );

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

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

Additional Support

Resources