Unlock balanced power with TPS65131 and STM32G474RE
From minus to plus
Published Nov 08, 2024
Click board™
Boost-INV 2 Click
Dev Board
Nucleo 64 with STM32G474RE MCU
Compiler
NECTO Studio
MCU
STM32G474RE
Embrace the symmetry of power with our dual-polarity voltage conversion solution
A
A
Hardware Overview
How does it work?
Boost-INV 2 Click is based on the TPS65131, a positive and negative output DC/DC converter from Texas Instruments. Two D/A converters are connected to the positive and negative voltage feedback loop of the TPS65131. The positive and the negative loops are fed into the internal error amplifiers, which compare the feedback voltage with the internal references. They change the duty cycle of the output switching sections to compensate for the differences (errors), affecting the output voltage that way. Incorporating a D/A converter into the feedback loop allows programmed "errors" to be introduced into the loop, allowing control over the output voltage. The TPS65131 IC uses the fixed frequency PWM signal to switch output stages. The internal current limit is about 1950mA for both the inverting and boost converter. The output voltage is clean while running in the continuous conduction mode, with no significant ripple and noise. The complete disconnect of both inverting and boosting converter stages allows no source current to flow through the converter while it is unpowered. This prevents battery draining, allowing the device to use the battery power and providing a split-rail power supply for various applications. Two D/A converters (DAC) labeled as MCP4291, 12-Bit DACs with the SPI Interface by Microchip, are used in feedback loops. One of the DACs is connected
to the MCP6H02 op-amp, configured as the inverting unity gain amplifier. It inverts the polarity of the DAC signal. The feedback voltage of the inverting converter can vary from 0V (Vref) to -15V. Therefore, the DAC signal, which commonly ranges from 0 to +VREF, needs to be inverted. For the boost converter, there is no need to invert the DAC, so its voltage goes up to +VREF. There are two separate CS pins (Chip Select) for these DACs, so both can be programmed independently. Those Chip Select pins are routed to the RST and CS pins of the mikroBUS™ and are labeled as CSN for the negative voltage-controlling DAC and CSP for the positive voltage-controlling DAC. Two more auxiliary ICs are used on the Boost-INV 2 click. One IC is the ADM8829, a switched-capacitor voltage inverter that provides a negative supply voltage for the inverting op-amp. The other IC is the MCP1501, a high-precision buffered voltage reference required for the DACs (4.096 V). The TPS65131 converter IC can be operated in the Power Saving mode. This is very useful for low currents because the device will power itself down as long as the voltage across the output stays above the internally set threshold. When the voltage drops under this threshold, the converter powers up produces several switching pulses that recover the nominal voltage value across the load, and power down again. Depending on the connected
load, it will take more or less time to drain the charge from the inductor. Unlike the normal mode, which operates in the continuous-conduction mode (CCM), the power-saving mode allows the converter to switch between CCM and DCM (discontinuous-conduction) modes. The Click board™ has its PWM pin routed to the PSP and PSN pins of the TPS65131 IC, and the HIGH logic level on this pin will put the IC into the Power Saving mode. The PWM pin of the mikroBUS™ is labeled as the PSM on this Click board™. When the ENP and ENN pins of the TPS65131 IC are at the LOW logic level, the device is completely powered down, disconnecting the loads described above and preventing current leakage through the passive elements of the circuit. These pins are routed to the AN pin of the mikroBUS™ and labeled as EN, allowing the host MCU to control the operation of the Click board™ By default, the input voltage is taken from the mikroBUS™ +5V power rail. An onboard VIN SEL jumper allows selection between the +5V from the mikroBUS™ or an external power supply connected to the screw terminal input, labeled as VEXT. The remaining two screw terminals are negative and positive voltage outputs labeled V- and V+. All three screw terminals share a common GND.
Features overview
Development board
Nucleo-64 with STM32G474R 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)
128k
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
Click board™ Schematic
Step by step
Project assembly
Start by selecting your development board and Click board™. Begin with the Nucleo 64 with STM32G474RE MCU as your development board.
Track your results in real time
Application Output
This Click board can be interfaced and monitored in two ways:
Application Output- Use the "Application Output" window in Debug mode for real-time data monitoring. Set it up properly by following this tutorial.
UART Terminal- Monitor data via the UART Terminal using a USB to UART converter. For detailed instructions, check out this tutorial.
Software Support
Library Description
This library contains API for Boost-INV 2 Click driver.
Key functions:
boostinv2_set_positive_voltage- Functions for set positive output voltageboostinv2_set_negative_voltage- Functions for set negative output voltageboostinv2_generic_transfer- Generic transfer function
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 boostinv2 Click example
*
* # Description
* First increse positiv voltage by 2V every 3 seconda, then
* decrese negative value for -2v every 3 seconds.
*
* The demo application is composed of two sections :
*
* ## Application Init
* Initializes Driver init and enable chip
*
* ## Application Task
* Changes the positive and negative output voltage.
* Positive output voltage goes from 5V to 15V.
* Negative output voltage goes from -5V to -15V
*
* \author MikroE Team
*
*/
// ------------------------------------------------------------------- INCLUDES
#include "board.h"
#include "log.h"
#include "boostinv2.h"
// ------------------------------------------------------------------ VARIABLES
static boostinv2_t boostinv2;
static log_t logger;
// ------------------------------------------------------ APPLICATION FUNCTIONS
void application_init ( void )
{
log_cfg_t log_cfg;
boostinv2_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.
boostinv2_cfg_setup( &cfg );
BOOSTONV2_MAP_MIKROBUS( cfg, MIKROBUS_1 );
boostinv2_init( &boostinv2, &cfg );
boostinv2_enable( &boostinv2 );
}
void application_task ( void )
{
// Positive output voltage
log_printf( &logger, "VOUT = 6V\r\n");
boostinv2_set_positive_voltage( &boostinv2, BOOSTINV2_POS_VOUT_6V );
Delay_ms( 3000 );
log_printf( &logger, "VOUT = 8V\r\n");
boostinv2_set_positive_voltage( &boostinv2, BOOSTINV2_POS_VOUT_8V );
Delay_ms( 3000 );
log_printf( &logger, "VOUT = 12V\r\n");
boostinv2_set_positive_voltage( &boostinv2, BOOSTINV2_POS_VOUT_12V );
Delay_ms( 3000 );
log_printf( &logger, "VOUT = 14V\r\n");
boostinv2_set_positive_voltage( &boostinv2, BOOSTINV2_POS_VOUT_14V );
Delay_ms( 3000 );
log_printf( &logger, "VOUT = 12V\r\n");
boostinv2_set_positive_voltage( &boostinv2, BOOSTINV2_POS_VOUT_12V );
Delay_ms( 3000 );
log_printf( &logger, "VOUT = 8V\r\n");
boostinv2_set_positive_voltage( &boostinv2, BOOSTINV2_POS_VOUT_8V );
Delay_ms( 3000 );
// Negative output voltage
log_printf( &logger, "VOUT = -5V\r\n");
boostinv2_set_negative_voltage( &boostinv2, BOOSTINV2_NEG_VOUT_5V );
Delay_ms( 3000 );
log_printf( &logger, "VOUT = -7V\r\n");
boostinv2_set_negative_voltage( &boostinv2, BOOSTINV2_NEG_VOUT_7V );
Delay_ms( 3000 );
log_printf( &logger, "VOUT = -13V\r\n");
boostinv2_set_negative_voltage( &boostinv2, BOOSTINV2_NEG_VOUT_13V );
Delay_ms( 3000 );
log_printf( &logger, "VOUT = -7V\r\n");
boostinv2_set_negative_voltage( &boostinv2, BOOSTINV2_NEG_VOUT_7V );
Delay_ms( 3000 );
}
void main ( void )
{
application_init( );
for ( ; ; )
{
application_task( );
}
}
// ------------------------------------------------------------------------ END
Additional Support
Resources
Category:Boost
