Transform voltage like never before with MPM3530 and STM32L151ZD
Sync your power needs
Published Aug 01, 2023
Click board™
Buck 13 Click
Dev Board
Fusion for STM32 v8
Compiler
NECTO Studio
MCU
STM32L151ZD
Ensure your electronics receive the necessary power, minimizing waste and enhancing performance
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Hardware Overview
How does it work?
Buck 13 Click is based on the MPM3530, a 55V 3A ultra-low profile DC-to-DC power module by Monolithic Power Systems (MPS). This IC is a valley current mode controlled power module, meaning that it responds faster than the traditional peak current mode control, thus, a better response to transients. This IC requires minimal external components, making the whole device robust and easy to work with. The feedback voltage on the FB pin determines the output voltage. Therefore, Buck 13 click has a fixed voltage divider calculated to ensure stable, the most frequently used, 3.3V output. The MPM3530 operates at a high switching frequency of 520 kHz, which allows a good compromise between the efficiency and the device's size, with no external coil needed and a minimal number of other external components. This Click board™ also uses the MCP3001, a 10-bit A/D converter (ADC) which uses the SPI interface from Microchip. It allows monitoring of the
output voltage over the SPI interface. This ADC is powered by the +5V mikroBUS™ power rail. The same voltage is also used to supply the MCP1541 voltage reference. That way, the stable 4.096V reference voltage is obtained to ensure precise output voltage measurement. The Click board™ itself requires an external power supply to be connected at the input terminal, labeled as VIN. The VOUT terminal provides the connected load with the regulated 3.3V voltage. The over-current protection is based on cycle-by-cycle limiting of the inductor current. If the output voltage starts to drop during the current limiting interval, causing the FB voltage to drop under 50% of the internal reference, the device enters the hiccup mode, shutting down the output. After a fixed period, the device will try to re-enable the output. If the short-circuit condition still exists, it will shut down the output again, repeating the whole process until the short-circuit condition disappears. The hiccup
mode greatly reduces the short-circuit current, protecting the device when the output is shorted to ground. Thanks to its ability to work with the high-duty cycle of the internal switching PWM signal, the MPM3530 requires the input voltage to be only about 0.7V above the output voltage to maintain the regulation. However, if the input voltage drops under 3.5V, the device cannot operate properly. Therefore, the under-voltage protection shuts down the device as a protection measure. The under-voltage protection is disabled once the input voltage exceeds 3.9V. This small hysteresis of 0.4V prevents erratic behavior in border cases. As mentioned before, the voltage of the power supply at the input terminal should stay within the range between 4V and 55V. However, the voltage at the input should be approximately 5.7V to 6V, at least, to provide good regulation at the output.
Features overview
Development board
Fusion for STM32 v8 is a development board specially designed for the needs of rapid development of embedded applications. It supports a wide range of microcontrollers, such as different 32-bit ARM® Cortex®-M based MCUs from STMicroelectronics, regardless of their number of pins, and a broad set of unique functions, such as the first-ever embedded debugger/programmer over WiFi. 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, Fusion for STM32 v8 provides a fluid and immersive working experience, allowing
access anywhere and under any circumstances at any time. Each part of the Fusion for STM32 v8 development board contains the components necessary for the most efficient operation of the same board. An advanced integrated CODEGRIP programmer/debugger module offers many valuable programming/debugging options, including support for JTAG, SWD, and SWO Trace (Single Wire Output)), and seamless integration with the Mikroe software environment. Besides, it 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 HOST/DEVICE, CAN (on the MCU card, if supported), and Ethernet is also included. In addition, it also has the well-established mikroBUS™ standard, a standardized socket for the MCU card (SiBRAIN standard), and two display options for the TFT board line of products and character-based LCD. Fusion for STM32 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.
Microcontroller Overview
MCU Card / MCU
Type
8th Generation
Architecture
ARM Cortex-M3
MCU Memory (KB)
384
Silicon Vendor
STMicroelectronics
Pin count
144
RAM (Bytes)
49152
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 Fusion for STM32 v8 as your development board.
Track your results in real time
Application Output via UART Mode
1. Once the code example is loaded, pressing the "FLASH" button initiates the build process, and programs it on the created setup.
2. After the programming is completed, click on the Tools icon in the upper-right panel, and select the UART Terminal.
3. After opening the UART Terminal tab, first check the baud rate setting in the Options menu (default is 115200). If this parameter is correct, activate the terminal by clicking the "CONNECT" button.
4. Now terminal status changes from Disconnected to Connected in green, and the data is displayed in the Received data field.
Software Support
Library Description
This library contains API for Buck 13 Click driver.
Key functions:
buck13_enable- Enables the Buck 13 outputbuck13_get_adc- Gets the ADC values from the modulebuck13_get_voltage- Gets the 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
* \brief Buck13 Click example
*
* # Description
* This example switches the output of the Buck13 and logs the output voltage
* on the Vout terminal.
*
* The demo application is composed of two sections :
*
* ## Application Init
* Initializes SPI serial interface and turns OFF the Buck 13 output as default state.
*
* ## Application Task
* Displays the output voltage every 2 seconds.
*
* *note:*
* Input voltage range must be from 6.5 to 50V.
* Output voltage is about 3.3V.
* Current limit is 3A.
*
* \author Petar Suknjaja
*
*/
// ------------------------------------------------------------------- INCLUDES
#include "board.h"
#include "log.h"
#include "buck13.h"
// ------------------------------------------------------------------ VARIABLES
static buck13_t buck13;
static log_t logger;
static uint16_t out_voltage;
// ------------------------------------------------------ APPLICATION FUNCTIONS
void application_init ( void )
{
log_cfg_t log_cfg;
buck13_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.
buck13_cfg_setup( &cfg );
BUCK13_MAP_MIKROBUS( cfg, MIKROBUS_1 );
buck13_default_cfg ( &buck13 );
buck13_init( &buck13, &cfg );
log_info( &logger, "Buck 13 is enabled now" );
}
void application_task ( void )
{
// Task implementation.
buck13_enable( &buck13, BUCK13_ENABLE );
out_voltage = buck13_get_voltage( &buck13 );
log_printf( &logger, "Vout = %d mV\r\n", out_voltage );
Delay_ms( 2000 );
}
void main ( void )
{
application_init( );
for ( ; ; )
{
application_task( );
}
}
// ------------------------------------------------------------------------ END
