ADC Oversampliong Demo application for XMEGA A3BU Xplained Documentation

Introduction

This Projects demonstrates:

• How to implement oversampling application with XMEGA ADC :
  The oversampling is used to increase the resolution of ADC hardware by implementing signal processing in firmware. In this example,configuration has been selected to increase resolution from 12 bit signed to 16 bit signed
• More information can be obtained from application note "Atmel AVR1629: XMEGA ADC Oversampling"

Main Files

• oversampling.c : Oversampling demo application main file
• adc_oversampling.c : ADC applications and signal processing functions related to oversampling
• conf_oversampling.h : Configuration Macros for oversampling

References

• Refer Application Note: AVR121: Enhancing ADC resolution by oversampling
• Refer Application Note: AVR120: ADC Characteristics and Calibration
• Refer Application Note: AVR1300: Using the XMEGA ADC
• Refer Application Note: AVR1505: XMEGA-A1 Xplained training - XMEGA ADC

Device Info

All AVR XMEGA device. This example have been tested with following setup:

• XMEGA-A3BU Xplained

Description of the example

• All configurations related to oversampling level, ADC input pin, reference voltages, reference source and gain error factor are available from conf_oversampling.h file.
• To calculate a single result, this demo application will use number of sample as per configuration and perform signal processing to get higher resolution ADC result.
• After oversampling process, the converted analog input voltage and also ADC counts are displayed on LCD available in XMEGA-A3BU Xplained kit.
• Also, for comparison purpose, analog input voltage is calculated with only one sample(i.e. without oversampling) and this analog input voltage and corresponding ADC counts are displayed on LCD.

Compilation info

This software was written for the GNU GCC and IAR for AVR. Other compilers may or may not work.

Contact Information

For further information, visit Microchip.