Unleash efficiency and performance with step-down/step-up regulator based on MIC23099 and PIC18LF27K42

AA/AAA cell buck-boost

Published Nov 01, 2023

Click board™

MIC23099 Click

Dev. board

EasyPIC v7

Compiler

NECTO Studio

MCU

PIC18LF27K42

Efficiently manage the power supply for electronic devices that require a voltage different from that provided by a single AA or AAA battery

Hardware Overview

How does it work?

MIC23099 Click is based on the MIC23099, a single AA/AAA cell step-down/step-up regulator with battery monitoring from Microchip. This Click is designed to run on a 3.3V power supply. It communicates with the target microcontroller over the following pins on the mikroBUS™ line: CS, INT. MIC23099 Click has three screw terminals (Buck 1V, GND, and Boost 3V3) which are outputs

for connecting some external consumers. The low-battery level is indicated by an onboard STAT LED. The MIC23099 is not a battery charger but needs a battery to work properly. The battery is not included. The MIC23099 is a high-efficiency, low-noise, dual output, integrated power management solution for single-cell alkaline or NiMH battery applications. Both converters are

designed to operate with a minimum switching frequency of 80 kHz for the buck and 100 kHz for the boost to minimize switching artifacts in the audio band. The high-current boost has a maximum switching frequency of 1 MHz, minimizing the solution footprint. The MIC23099 incorporates both battery management functions and fault protection.

Features overview

Development board

EasyPIC v7 is the seventh generation of PIC development boards specially designed to develop embedded applications rapidly. It supports a wide range of 8-bit PIC microcontrollers from Microchip and has a broad set of unique functions, such as a powerful onboard mikroProg programmer and In-Circuit debugger over USB-B. The development board is well organized and designed so that the end-user has all the necessary elements in one place, such as switches, buttons, indicators, connectors, and others. With four different connectors for each port, EasyPIC v7 allows you to connect accessory boards, sensors, and custom electronics more efficiently than ever. Each part of

the EasyPIC v7 development board contains the components necessary for the most efficient operation of the same board. An integrated mikroProg, a fast USB 2.0 programmer with mikroICD hardware In-Circuit Debugger, offers many valuable programming/debugging options and seamless integration with the Mikroe software environment. Besides it also includes a clean and regulated power supply block for the development board. It can use various external power sources, including an external 12V power supply, 7-23V AC or 9-32V DC via DC connector/screw terminals, and a power source via the USB Type-B (USB-B) connector. Communication options such as

USB-UART and RS-232 are also included, alongside the well-established mikroBUS™ standard, three display options (7-segment, graphical, and character-based LCD), and several different DIP sockets. These sockets cover a wide range of 8-bit PIC MCUs, from PIC10F, PIC12F, PIC16F, PIC16Enh, PIC18F, PIC18FJ, and PIC18FK families. EasyPIC v7 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)

128

Silicon Vendor

Microchip

Pin count

RAM (Bytes)

8192

Used MCU Pins

mikroBUS™ mapper

RST

Enable

RA5

SCK

MISO

MOSI

Power Supply

3.3V

Ground

GND

PWM

Power Good Indicator

RB1

INT

SCL

SDA

Ground

GND

Take a closer look

Click board™ Schematic

Step by step

Project assembly

EasyPIC v7 front image hardware assembly

Start by selecting your development board and Click board™. Begin with the EasyPIC v7 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 v7 Access MB 1 - upright/background hardware assembly

NECTO Compiler Selection Step Image hardware assembly

Necto DIP image step 7 hardware assembly

EasyPIC PRO v7a Display Selection 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 MIC23099 Click driver.

Key functions:

mic23099_default_cfg - This function executes default configuration for MIC23099 Click
mic23099_check_power_good - This function checks the state of Power Good output pin

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 
 * \brief MIC23099 Click example
 * 
 * # Description
 * MIC23099 click represent single AA/AAA cell step-down/step-up regulator 
 * with battery monitoring.
 *
 * The demo application is composed of two sections :
 * 
 * ## Application Init 
 * Application Init performs Logger and Click initialization.
 * 
 * ## Application Task  
 * This example demonstrates the use of MIC23099 Click board by checking 
 * the state of power good pin and sends note via UART Terminal 
 * if the state is low.
 * 
 * \author Mihajlo Djordjevic
 *
 */
// ------------------------------------------------------------------- INCLUDES

#include "board.h"
#include "log.h"
#include "mic23099.h"

// ------------------------------------------------------------------ VARIABLES

static mic23099_t mic23099;
static log_t logger;

static uint8_t new_stat;
static uint8_t old_stat;

// ------------------------------------------------------- ADDITIONAL FUNCTIONS


// ------------------------------------------------------ APPLICATION FUNCTIONS

void application_init ( void )
{
    log_cfg_t log_cfg;
    mic23099_cfg_t cfg;

    /** 
     * 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_printf( &logger, "--------------------------\r\n" );
    log_printf( &logger, "     Application  Init\r\n" );
    Delay_ms ( 1000 );

    //  Click initialization.

    mic23099_cfg_setup( &cfg );
    MIC23099_MAP_MIKROBUS( cfg, MIKROBUS_1 );
    mic23099_init( &mic23099, &cfg );
    
    log_printf( &logger, "--------------------------\r\n" );
    log_printf( &logger, " ---- MIC23099 Click ---- \r\n" );
    log_printf( &logger, "--------------------------\r\n" );
    Delay_ms ( 1000 );
    
    mic23099_default_cfg( &mic23099 );
    Delay_ms ( 1000 );
    
    new_stat = MIC23099_DISABLE;
    old_stat = MIC23099_ENABLE;
    
    log_printf( &logger, " -- Initialization done --\r\n" );
    log_printf( &logger, "--------------------------\r\n" );
    Delay_ms ( 1000 );
}

void application_task ( void )
{  
    new_stat = mic23099_check_power_good( &mic23099 );

    if ( new_stat == MIC23099_ENABLE && old_stat == MIC23099_DISABLE )
    {
        old_stat = MIC23099_ENABLE;
    }

    if ( new_stat == MIC23099_DISABLE && old_stat == MIC23099_ENABLE )
    {
        log_printf( &logger, " Change  battery  and  reset. \r\n" );
        log_printf( &logger, "------------------------------\r\n" );
        old_stat = MIC23099_DISABLE;
    }
}

void main ( void )
{
    application_init( );

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

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