Produce an output voltage that is less than its input with TPSM63610 and STM32F091RC
Adjusting power for perfect performance
Published Feb 26, 2024
Click board™
Step Down 10 Click
Dev Board
Nucleo-64 with STM32F091RC MCU
Compiler
NECTO Studio
MCU
STM32F091RC
Make sure your device gets the right "language" of power, even if the power source speaks a different voltage "language"
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Hardware Overview
How does it work?
Step Down 10 Click is based on the TPSM63610, a high-density synchronous buck DC/DC power module with enhanced HotRodTM from Texas Instruments. The TPSM63610 features up to 95% efficiency, ultra-low conducted and radiated EMI signatures, several protection mechanisms, and more. The feedback input of the TPSM63610 that sets the desired voltage output regulation consists of a voltage divider, of which one part is the MCP4661T, a dual digital POT with non-volatile memory from Microchip. The MCP4661T is a 100K potentiometer in 8-bit resolution, has 256 wiper steps, and can store values in the internal EEPROM. The TPSM63610 also has an adjustable frequency of 2.2MHz up to 400kHz, which can be selected over the onboard digital potentiometer or set as a fixed value over the unpopulated R12
resistor. The values are in the table of the attached Step Down 10 Click schematic. There are two screw terminals for connecting input and output voltages. The Step Down 10 Click features an additional 3-pin header. This header allows you to improve efficiency by connecting the VLDO as an input bias voltage to the VOUT as an output voltage. You can also improve noise immunity by connecting the VLDO to GND with a 0.1 μF to 1 μF capacitor. If the output voltage is above the 12V, connect VLDO to GND. Step Down 10 Click uses a standard 2-Wire I2C interface of the MCP4661T to allow the host MCU to set the output voltage, supporting clock frequencies up to 3.4MHz. The I2C address can be selected over the ADDR SEL jumper (0 set by default). The power-good PG pin will be asserted if the output voltage is not within
the specified window threshold. Over the MD pin, you can set the mode of operation for this module. You can choose between auto mode, forced pulse width modulation, and synchronization with an external clock, in this case, set over the digital potentiometer (or resistor). 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.
Features overview
Development board
Nucleo-64 with STM32F091RC 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-M0
MCU Memory (KB)
256
Silicon Vendor
STMicroelectronics
Pin count
64
RAM (Bytes)
32768
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.
Used MCU Pins
mikroBUS™ mapper
Take a closer look
Schematic
Step by step
Project assembly
Start by selecting your development board and Click board™. Begin with the Nucleo-64 with STM32F091RC MCU as your development board.
Track your results in real time
Application Output via Debug Mode
1. Once the code example is loaded, pressing the "DEBUG" button initiates the build process, programs it on the created setup, and enters Debug mode.
2. After the programming is completed, a header with buttons for various actions within the IDE becomes visible. Clicking the green "PLAY" button starts reading the results achieved with the Click board™. The achieved results are displayed in the Application Output tab.
Software Support
Library Description
This library contains API for Step Down 10 Click driver.
Key functions:
stepdown10_get_pg_state- Step Down 10 get PG pin state function.stepdown10_set_wiper_pos- Step Down 10 set wiper position.stepdown10_set_output- Step Down 10 set output voltage.
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 10 Click example
*
* # Description
* This library contains API for the Step Down 10 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 2 V.
*
* ## Application Task
* This example demonstrates the use of the Step Down 10 Click board™ by changing
* output voltage every 2 seconds starting from 2 V up to 20 V.
*
* @author Stefan Ilic
*
*/
#include "board.h"
#include "log.h"
#include "stepdown10.h"
static stepdown10_t stepdown10;
static log_t logger;
void application_init ( void )
{
log_cfg_t log_cfg; /**< Logger config object. */
stepdown10_cfg_t stepdown10_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.
stepdown10_cfg_setup( &stepdown10_cfg );
STEPDOWN10_MAP_MIKROBUS( stepdown10_cfg, MIKROBUS_1 );
if ( I2C_MASTER_ERROR == stepdown10_init( &stepdown10, &stepdown10_cfg ) )
{
log_error( &logger, " Communication init." );
for ( ; ; );
}
if ( STEPDOWN10_ERROR == stepdown10_default_cfg ( &stepdown10 ) )
{
log_error( &logger, " Default configuration." );
for ( ; ; );
}
log_info( &logger, " Application Task " );
}
void application_task ( void )
{
for ( uint8_t n_cnt = STEPDOWN10_MIN_OUTPUT; n_cnt <= STEPDOWN10_MAX_OUTPUT; n_cnt++ )
{
stepdown10_set_output( &stepdown10, ( float ) n_cnt );
log_printf( &logger, " Output voltage %d V\r\n", ( uint16_t ) n_cnt );
Delay_ms( 2000 );
}
}
int main ( void )
{
application_init( );
for ( ; ; )
{
application_task( );
}
return 0;
}
// ------------------------------------------------------------------------ END
