RMS to DC 2 Click is a compact add-on board that converts the RMS of the input signal into a DC voltage. This board features the AD8436, a low-cost, low-power, true RMS-to-DC converter from Analog Devices. The AD8436 is a translinear precision, low-power, true RMS-to-DC converter that delivers true RMS or average rectified value of AC waveform. It features high accuracy, a wide dynamic input range (100μV rms to 3V rms), a wide bandwidth of up to 1MHz, and more. This Click board™ makes the perfect solution for the development of various true RMS digital multimeter applications, panel meters and gauges, AC + DC measurement applications, a true RMS measurement of an audio signal, and other similar applications that require accurate RMS value readings.
- Author : Stefan Filipovic
- Date : Apr 2023.
- Type : ADC/I2C type
We provide a library for the RMS to DC 2 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.
This library contains API for RMS to DC 2 Click driver.
rmstodc2_cfg_setup
Config Object Initialization function.
void rmstodc2_cfg_setup ( rmstodc2_cfg_t *cfg );
rmstodc2_init
Initialization function.
err_t rmstodc2_init ( rmstodc2_t *ctx, rmstodc2_cfg_t *cfg );
rmstodc2_set_vref
This function sets the voltage reference for RMS to DC 2 Click driver.
err_t rmstodc2_set_vref ( rmstodc2_t *ctx, float vref );
rmstodc2_read_voltage
This function reads raw ADC value and converts it to proportional voltage level.
err_t rmstodc2_read_voltage ( rmstodc2_t *ctx, float *voltage );
This example demonstrates the use of the RMS to DC 2 Click board by measuring the RMS voltage of the input signal.
The demo application is composed of two sections :
Initializes the driver and logger.
void application_init ( void )
{
log_cfg_t log_cfg; /**< Logger config object. */
rmstodc2_cfg_t rmstodc2_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.
rmstodc2_cfg_setup( &rmstodc2_cfg );
RMSTODC2_MAP_MIKROBUS( rmstodc2_cfg, MIKROBUS_1 );
err_t init_flag = rmstodc2_init( &rmstodc2, &rmstodc2_cfg );
if ( ( ADC_ERROR == init_flag ) || ( I2C_MASTER_ERROR == init_flag ) )
{
log_error( &logger, " Communication init." );
for ( ; ; );
}
log_info( &logger, " Application Task " );
}
Reads the RMS voltage of the input signal and displays the results on the USB UART approximately once per second.
void application_task ( void )
{
float voltage = 0;
if ( RMSTODC2_OK == rmstodc2_read_voltage ( &rmstodc2, &voltage ) )
{
log_printf( &logger, " RMS voltage : %.3f[V]\r\n\n", voltage * RMSTODC2_RMS_VOLTAGE_COEF );
Delay_ms ( 1000 );
}
}
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.RMStoDC2
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.