Redefine how you sense and measure inductance with LDC1041 and ATmega32
Infinite possibilities, one converter: Inductance-to-Digital marvel!
Published Nov 01, 2023
Click board™
LDC 2 Click
Dev. board
EasyAVR v7
Compiler
NECTO Studio
MCU
ATmega32
Elevate your measurement capabilities with our inductance-to-digital converter, an essential tool for engineers and researchers seeking high-precision sensing in fields like robotics, instrumentation, and materials science
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Hardware Overview
How does it work?
LDC 2 Click is based on the LDC1041, an inductance-to-digital converter simultaneously measuring an LC resonator's impedance and resonant frequency from Texas Instruments. This Click board™ is easy to use, requiring only the sensor frequency within 5kHz and 5MHz to begin sensing, and demonstrates the use of inductive sensing technology to sense and measure a conductive target object's presence, position, or composition. In addition, the LDC1041 also measures the oscillation frequency of the LC circuit, which is used to determine the inductance of the LC circuit. The device then outputs a digital value that is inversely proportional to frequency. The LDC measures the inductance change that a conductive target causes when it moves into the inductor's AC magnetic field to provide information about the target's position over a
sensor coil. The inductance shift is caused by eddy currents (circulating currents) generated in the target due to the sensor's magnetic field. These eddy currents generate a secondary magnetic field that opposes the sensor field, causing a shift in the observed inductance, used for precise positioning of the target as it moves laterally over the sensor coil. Also, the LDC1041 has two power modes: Active and Standby Mode. Active Mode enables proximity data and frequency data conversion, while Standby mode represents the default mode on the devices' Power-Up sequence. In Standby Mode, the conversion process is disabled. This Click board™ comes with an example of a PCB sensor coil designed to give the user maximum flexibility. The LDC1041 communicates with MCU using the standard SPI serial interface with a maximum frequency of
4MHz. In addition to this serial interface, one GPIO pin connected to the mikroBUS™ socket is also used. The configurable interrupt pin routed to the INT pin of the mikroBUS™ socket may be configured in three different ways by programming the interrupt Terminal mode register with SPI. An interrupt pin can act as a proximity switch, wake-up feature, or data-ready pin, indicating a valid condition for new data availability. This Click board™ can be operated only with a 5V logic voltage level. The board must perform appropriate logic voltage level conversion before using MCUs with different logic levels. Also, it comes equipped with a library containing functions and an example code that can be used as a reference for further development.
Features overview
Development board
EasyAVR v7 is the seventh generation of AVR development boards specially designed for the needs of rapid development of embedded applications. It supports a wide range of 16-bit AVR microcontrollers from Microchip and has a broad set of unique functions, such as a powerful onboard mikroProg programmer and In-Circuit debugger over USB. The development board is well organized and designed so that the end-user has all the necessary elements in one place, such as switches, buttons, indicators, connectors, and others. With four different connectors for each port, EasyAVR v7 allows you to connect accessory boards, sensors, and custom electronics more
efficiently than ever. Each part of the EasyAVR v7 development board contains the components necessary for the most efficient operation of the same board. An integrated mikroProg, a fast USB 2.0 programmer with mikroICD hardware In-Circuit Debugger, offers many valuable programming/debugging options and seamless integration with the Mikroe software environment. Besides it also includes a clean and regulated power supply block for the development board. It can use a wide range of external power sources, including an external 12V power supply, 7-12V AC or 9-15V DC via DC connector/screw terminals, and a power source via the USB Type-B (USB-B)
connector. Communication options such as USB-UART and RS-232 are also included, alongside the well-established mikroBUS™ standard, three display options (7-segment, graphical, and character-based LCD), and several different DIP sockets which cover a wide range of 16-bit AVR MCUs. EasyAVR v7 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
Architecture
AVR
MCU Memory (KB)
32
Silicon Vendor
Microchip
Pin count
40
RAM (Bytes)
2048
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 EasyAVR v7 as your development board.
Track your results in real time
Application Output
1. Application Output - In Debug mode, the 'Application Output' window enables real-time data monitoring, offering direct insight into execution results. Ensure proper data display by configuring the environment correctly using the provided tutorial.
2. UART Terminal - Use the UART Terminal to monitor data transmission via a USB to UART converter, allowing direct communication between the Click board™ and your development system. Configure the baud rate and other serial settings according to your project's requirements to ensure proper functionality. For step-by-step setup instructions, refer to the provided tutorial.
3. Plot Output - The Plot feature offers a powerful way to visualize real-time sensor data, enabling trend analysis, debugging, and comparison of multiple data points. To set it up correctly, follow the provided tutorial, which includes a step-by-step example of using the Plot feature to display Click board™ readings. To use the Plot feature in your code, use the function: plot(*insert_graph_name*, variable_name);. This is a general format, and it is up to the user to replace 'insert_graph_name' with the actual graph name and 'variable_name' with the parameter to be displayed.
Software Support
Library Description
This library contains API for LDC 2 Click driver.
Key functions:
ldc2_measure_resonance_impedance- This function measures the resonance impedance and proximity dataldc2_measure_inductance- This function measures the inductance and sensor frequencyldc2_get_sensor_frequency- This function reads and calculates the sensor frequency.
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 main.c
* @brief LDC2 Click example
*
* # Description
* This example demonstrates the use of LDC 2 click board.
*
* The demo application is composed of two sections :
*
* ## Application Init
* Initializes the driver and configures the click board.
*
* ## Application Task
* Measures the resonance impedance and proximity as well as the inductance and sensor frequency
* approximately every 200ms and displays all values on the USB UART.
*
* @author Stefan Filipovic
*
*/
#include "board.h"
#include "log.h"
#include "ldc2.h"
static ldc2_t ldc2;
static log_t logger;
void application_init ( void )
{
log_cfg_t log_cfg; /**< Logger config object. */
ldc2_cfg_t ldc2_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 );
Delay_ms( 100 );
log_info( &logger, " Application Init " );
// Click initialization.
ldc2_cfg_setup( &ldc2_cfg );
LDC2_MAP_MIKROBUS( ldc2_cfg, MIKROBUS_1 );
if ( SPI_MASTER_ERROR == ldc2_init( &ldc2, &ldc2_cfg ) )
{
log_error( &logger, " Application Init Error. " );
log_info( &logger, " Please, run program again... " );
for ( ; ; );
}
if ( LDC2_ERROR == ldc2_default_cfg ( &ldc2 ) )
{
log_error( &logger, " Default Config Error. " );
log_info( &logger, " Please, run program again... " );
for ( ; ; );
}
log_info( &logger, " Application Task " );
}
void application_task ( void )
{
uint8_t prox_data = 0;
float rp_data = 0;
float freq = 0;
float inductance = 0;
if ( LDC2_OK == ldc2_measure_resonance_impedance( &ldc2, &prox_data, &rp_data ) )
{
log_printf( &logger, " Proximity: %u\r\n Resonance Impedance: %.3f kOhm\r\n\n", ( uint16_t ) prox_data, rp_data );
}
if ( LDC2_OK == ldc2_measure_inductance( &ldc2, &freq, &inductance ) )
{
log_printf( &logger, " Sensor Frequency: %.3f MHz\r\n Inductance: %.6f uH\r\n\n", freq, inductance );
}
Delay_ms( 200 );
}
void main ( void )
{
application_init( );
for ( ; ; )
{
application_task( );
}
}
// ------------------------------------------------------------------------ END
