30 min

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

AA/AAA cell buck-boost

MIC23099 Click with EasyPIC v7

Published Nov 01, 2023

Click board™

MIC23099 Click

Development board

EasyPIC v7


NECTO Studio



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.

MIC23099 Click top side image
MIC23099 Click bottom side image

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.

EasyPIC v7 horizontal image

Microcontroller Overview

MCU Card / MCU




MCU Memory (KB)


Silicon Vendor


Pin count


RAM (Bytes)


Used MCU Pins

mikroBUS™ mapper

Power Supply
Power Good Indicator

Take a closer look


MIC23099 Click Schematic 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.

EasyPIC v7 front image hardware assembly
LTE IoT 5 Click front image hardware assembly
MCU DIP 28 hardware assembly
LTE IoT 5 Click complete accessories setup image hardware assembly
EasyPIC v7 Access MB 2 - 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
EasyPIC PRO v7a Display Selection Necto Step 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 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

This example can be found in NECTO Studio. Feel free to download the code, or you can copy the code below.

 * \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

Additional Support