Create a high-efficiency power manager with LTC3586 and STM32F446RE
The future of battery management
Published Oct 08, 2024
Click board™
BATT-MAN Click
Dev. board
Nucleo 64 with STM32F446RE MCU
Compiler
NECTO Studio
MCU
STM32F446RE
Optimize battery performance and prolong its lifespan
A
A
Hardware Overview
How does it work?
BATT-MAN Click is based on the LTC3586, a high-efficiency power manager with boost, buck-boost, and dual buck converters from Analog Devices. It includes a high-efficiency current limited switching PowerPath™ manager with automatic load prioritization, which employs the Bat-Track™ adaptive output control technology, battery charger, and four synchronous switching regulators (two bucks, one buck-boost, and one boost). The LTC3586 has a working mode that sets the PowerPath™ manager never to exceed 1A of the input current. As soon as the device is plugged into the mikroBUS™ socket, it will detect the presence of the voltage from the 5V rail on the input pins (VBUS). PowerPath™ switching regulator will deliver power from VBUS to VOUT via the SW pin. The VOUT is used to drive external loads through the switching regulators, along with the integrated battery charger. If this combined current draw does not exceed the internally set current threshold, the voltage at the VOUT pin (VSYS on the included schematic) will be held at about 0.3V above the battery voltage level - thanks to the Bat-Track™ technology, keeping the losses across the battery charger to a minimum. If the combined current draw is large enough, the current available for the charger will be reduced to provide more current for the connected load. The PowerPath™ manager will always ensure that the connected load has priority over the battery charging. Only the excess power will be used for the charger section of the device. The provided internal ideal diode and the ideal diode controller allow the battery power to be used for the output. Whenever the VSYS drops under the VBAT level or
the load requires more current than is currently available from the input switching regulator, the additional power will be pulled from the battery via the ideal diode. This allows continuous power output for the connected external load as long as the connected battery is charged. The internal ideal diode is supplemented by the external MOSFET transistor, which is controlled by a dedicated GATE pin of the LTC3586 IC. There are several outputs available on BATT-MAN click. There is one LDO output voltage, regulated to 3.3V. This is a low current output, and it can provide about 30mA of current. This output is always on and intended only for very light loads. The second regulated 3.3V output is a high current output, which can provide up to 1A of current. Heavier loads can be connected to this output. Finally, a 5V regulated output can provide up to 800mA of current and is also meant for heavier loads. All these voltage connectors are accessed through the onboard screw terminals for an easy connection. The battery charging section has all the features required for optimized charging and prolonged battery life, including a constant current/voltage battery charger with automatic recharge, automatic termination by safety timer, low voltage trickle charging, and bad cell detection. The battery float voltage is set to 4.2V, perfectly suited for the LiPo batteries available at MikroElektronika online shop. The battery charging section also features the #CHRG pin, which indicates the battery's charging state. It can signalize several states of the battery: charging, not charging, and unresponsive/damaged battery. This is an open drain output, and it is pulled
HIGH to the 3.3V provided by the low current LDO regulator. When the battery is charging, this pin is pulled to a LOW state, and the red LED indicator on the BATT-MAN click is lit. When the battery is not charging, the LED is powered off. A 6.1Hz modulation signal is applied to the charge indicator LED if the connected battery is damaged. The #CHRG pin is routed to the mikroBUS™ AN pin. The #FAULT pin indicates an error in the output voltages. Suppose the feedback voltage of the integrated buck/boost converters fails to reach 8% of the internal reference voltage within 14ms. This pin will be pulled low to indicate the error, and the switching regulators will be shut off. The #FAULT pin is bidirectional, so pulling this pin LOW externally will also disable the switching regulators. This pin is routed to the mikroBUS™ INT pin and pulled HIGH to the 3.3V provided from the low current LDO regulator. The onboard EN Vout switch (SW1) can turn the device on, even without power from the mikroBUS™ 5V rail. In this case, the connected external LiPo battery is mandatory. EN pins of the switching regulators are routed to the mikroBUS™ RST pin, allowing the MCU to shut down the device. If the switch is in the closed position, it will pull the RST line of the mikroBUS™ to a HIGH level via the 3K3 resistor. If the MCU sets the RST pin to a LOW logic level, the RST pin will supersede the switch position, and the logic state of the RST pin will become LOW. Besides the onboard screw terminals used to connect the external load, the click board™ has a standard 2.54mm pitch battery connector to connect the LiPo battery.
Features overview
Development board
Nucleo-64 with STM32F446RE MCU offers a cost-effective and adaptable platform for developers to explore new ideas and prototype their designs. This board harnesses the versatility of the STM32 microcontroller, enabling users to select the optimal balance of performance and power consumption for their projects. It accommodates the STM32 microcontroller in the LQFP64 package and includes essential components such as a user LED, which doubles as an ARDUINO® signal, alongside user and reset push-buttons, and a 32.768kHz crystal oscillator for precise timing operations. Designed with expansion and flexibility in mind, the Nucleo-64 board features an ARDUINO® Uno V3 expansion connector and ST morpho extension pin
headers, granting complete access to the STM32's I/Os for comprehensive project integration. Power supply options are adaptable, supporting ST-LINK USB VBUS or external power sources, ensuring adaptability in various development environments. The board also has an on-board ST-LINK debugger/programmer with USB re-enumeration capability, simplifying the programming and debugging process. Moreover, the board is designed to simplify advanced development with its external SMPS for efficient Vcore logic supply, support for USB Device full speed or USB SNK/UFP full speed, and built-in cryptographic features, enhancing both the power efficiency and security of projects. Additional connectivity is
provided through dedicated connectors for external SMPS experimentation, a USB connector for the ST-LINK, and a MIPI® debug connector, expanding the possibilities for hardware interfacing and experimentation. Developers will find extensive support through comprehensive free software libraries and examples, courtesy of the STM32Cube MCU Package. This, combined with compatibility with a wide array of Integrated Development Environments (IDEs), including IAR Embedded Workbench®, MDK-ARM, and STM32CubeIDE, ensures a smooth and efficient development experience, allowing users to fully leverage the capabilities of the Nucleo-64 board in their projects.
Microcontroller Overview
MCU Card / MCU
Architecture
ARM Cortex-M4
MCU Memory (KB)
512
Silicon Vendor
STMicroelectronics
Pin count
64
RAM (Bytes)
131072
You complete me!
Accessories
Click Shield for Nucleo-64 comes equipped with two proprietary mikroBUS™ sockets, allowing all the Click board™ devices to be interfaced with the STM32 Nucleo-64 board with no effort. This way, Mikroe allows its users to add any functionality from our ever-growing range of Click boards™, such as WiFi, GSM, GPS, Bluetooth, ZigBee, environmental sensors, LEDs, speech recognition, motor control, movement sensors, and many more. More than 1537 Click boards™, which can be stacked and integrated, are at your disposal. The STM32 Nucleo-64 boards are based on the microcontrollers in 64-pin packages, a 32-bit MCU with an ARM Cortex M4 processor operating at 84MHz, 512Kb Flash, and 96KB SRAM, divided into two regions where the top section represents the ST-Link/V2 debugger and programmer while the bottom section of the board is an actual development board. These boards are controlled and powered conveniently through a USB connection to program and efficiently debug the Nucleo-64 board out of the box, with an additional USB cable connected to the USB mini port on the board. Most of the STM32 microcontroller pins are brought to the IO pins on the left and right edge of the board, which are then connected to two existing mikroBUS™ sockets. This Click Shield also has several switches that perform functions such as selecting the logic levels of analog signals on mikroBUS™ sockets and selecting logic voltage levels of the mikroBUS™ sockets themselves. Besides, the user is offered the possibility of using any Click board™ with the help of existing bidirectional level-shifting voltage translators, regardless of whether the Click board™ operates at a 3.3V or 5V logic voltage level. Once you connect the STM32 Nucleo-64 board with our Click Shield for Nucleo-64, you can access hundreds of Click boards™, working with 3.3V or 5V logic voltage levels.
Li-Polymer Battery is the ideal solution for devices that demand a dependable and long-lasting power supply while emphasizing mobility. Its compatibility with mikromedia boards ensures easy integration without additional modifications. With a voltage output of 3.7V, the battery meets the standard requirements of many electronic devices. Additionally, boasting a capacity of 2000mAh, it can store a substantial amount of energy, providing sustained power for extended periods. This feature minimizes the need for frequent recharging or replacement. Overall, the Li-Polymer Battery is a reliable and autonomous power source, ideally suited for devices requiring a stable and enduring energy solution. You can find a more extensive choice of Li-Polymer batteries in our offer.
Used MCU Pins
mikroBUS™ mapper
Take a closer look
Click board™ Schematic
Step by step
Project assembly
Start by selecting your development board and Click board™. Begin with the Nucleo 64 with STM32F446RE MCU as your development board.
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 BATT-MAN Click driver.
Key functions:
battman_set_enable- This function controls the operation of the boardbattman_get_charging_indicator- This function shows the charging status
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 BATT-MAN Click example
*
* # Description
* BATT-MAN click is a very versatile battery operated power manager. When powered via mikroBUS,
* it will charge the connected Li-Ion/Li-Po 3.7V battery, while providing the output voltage
* on all its outputs at the same time.
*
* The demo application is composed of two sections :
*
* ## Application Init
* Initializes the click driver and logger utility and enables the click board.
*
* ## Application Task
* Checks the charging indicator status, and in relation to its state
* it displays an appropriate message on USB UART.
*
* \author MikroE Team
*
*/
// ------------------------------------------------------------------- INCLUDES
#include "board.h"
#include "log.h"
#include "battman.h"
// ------------------------------------------------------------------ VARIABLES
static battman_t battman;
static log_t logger;
static uint8_t chg_flag;
// ------------------------------------------------------ APPLICATION FUNCTIONS
void application_init ( void )
{
log_cfg_t log_cfg;
battman_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_info( &logger, "---- Application Init ----" );
// Click initialization.
battman_cfg_setup( &cfg );
BATTMAN_MAP_MIKROBUS( cfg, MIKROBUS_1 );
battman_init( &battman, &cfg );
battman_set_enable( &battman, 1 );
log_printf( &logger, "BATT-MAN click enabled.\r\n" );
chg_flag = 0;
}
void application_task ( void )
{
if ( !battman_get_charging_indicator ( &battman ) )
{
if ( chg_flag == 1 )
{
log_printf( &logger, "Charging enabled.\r\n" );
}
chg_flag = 0;
}
else
{
if ( chg_flag == 0 )
{
log_printf( &logger, "Charging disabled.\r\n" );
}
chg_flag = 1;
}
}
void main ( void )
{
application_init( );
for ( ; ; )
{
application_task( );
}
}
// ------------------------------------------------------------------------ END
