LDO Click

LDO Click is a compact add-on board designed to regulate the output voltage of a power supply to a lower level with a very low dropout voltage. This board features the TPS7A83A, a low-noise, low-dropout linear regulator (LDO) from Texas Instruments capable of sourcing 2A with only 200mV of maximum dropout. The TPS7A8300A has a pin-programmable output voltage from 0.8V-3.95V with a 50mV resolution, or it can be adjustable from 0.8V-5.2V using an external resistor divider.

Click Product page

Click library

• Author : Stefan Filipovic
• Date : Feb 2023.
• Type : I2C type

Software Support

We provide a library for the LDO Click as well as a demo application (example), developed using MikroElektronika compilers. The demo can run on all the main MikroElektronika development boards.

Package can be downloaded/installed directly from NECTO Studio Package Manager(recommended way), downloaded from our LibStock™ or found on Mikroe github account.

Library Description

This library contains API for LDO Click driver.

Standard key functions :

• ldo_cfg_setup Config Object Initialization function.

  void ldo_cfg_setup ( ldo_cfg_t *cfg );

• ldo_init Initialization function.

  err_t ldo_init ( ldo_t *ctx, ldo_cfg_t *cfg );

• ldo_default_cfg Click Default Configuration function.

  err_t ldo_default_cfg ( ldo_t *ctx );

Example key functions :

• ldo_enable_device This function enables the device by setting the EN pin to HIGH logic state.

  void ldo_enable_device ( ldo_t *ctx );

• ldo_disable_device This function disables the device by setting the EN pin to LOW logic state.

  void ldo_disable_device ( ldo_t *ctx );

• ldo_set_vout This function sets the voltage output.

  err_t ldo_set_vout ( ldo_t *ctx, uint16_t vout );

Example Description

This example demonstrates the use of LDO Click by changing the output voltage.

The demo application is composed of two sections :

Application Init

Initializes the driver and performs the device default configuration.

void application_init ( void )
{
    log_cfg_t log_cfg;  /**< Logger config object. */
    ldo_cfg_t ldo_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.
    ldo_cfg_setup( &ldo_cfg );
    LDO_MAP_MIKROBUS( ldo_cfg, MIKROBUS_1 );
    if ( I2C_MASTER_ERROR == ldo_init( &ldo, &ldo_cfg ) ) 
    {
        log_error( &logger, " Communication init." );
        for ( ; ; );
    }

    if ( LDO_ERROR == ldo_default_cfg ( &ldo ) )
    {
        log_error( &logger, " Default configuration." );
        for ( ; ; );
    }

    log_info( &logger, " Application Task " );
}

Application Task

Changes the output voltage every 3 seconds and displays on the USB UART the currently set voltage output value.

void application_task ( void )
{
    static uint16_t vout = LDO_VOUT_MIN;
    if ( LDO_OK == ldo_set_vout ( &ldo, vout ) )
    {
        log_printf ( &logger, " VOUT: %u mV\r\n\n", vout );
    }
    vout += LDO_VOUT_STEP;
    if ( vout > LDO_VOUT_MAX )
    {
        vout = LDO_VOUT_MIN;
    }
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
}

Note

In order to have up to 3950mV at VOUT you will need to move the VIN SEL on-board jumper to the VEXT position and provide at least 3950mV voltage input at the VEXT terminal. Otherwise, the maximum level of VOUT will be limited to 3.3V system voltage.

The full application code, and ready to use projects can be installed directly from NECTO Studio Package Manager(recommended way), downloaded from our LibStock™ or found on Mikroe github account.

Other Mikroe Libraries used in the example:

• MikroSDK.Board
• MikroSDK.Log
• Click.LDO

Additional notes and informations

Depending on the development board you are using, you may need USB UART Click, USB UART 2 Click or RS232 Click to connect to your PC, for development systems with no UART to USB interface available on the board. UART terminal is available in all MikroElektronika compilers.