SPRAD55 March   2023 TMS320F2800132 , TMS320F2800133 , TMS320F2800135 , TMS320F2800137 , TMS320F2800152-Q1 , TMS320F2800153-Q1 , TMS320F2800154-Q1 , TMS320F2800155 , TMS320F2800155-Q1 , TMS320F2800156-Q1 , TMS320F2800157 , TMS320F2800157-Q1 , TMS320F280021 , TMS320F280021-Q1 , TMS320F280023 , TMS320F280023-Q1 , TMS320F280023C , TMS320F280025 , TMS320F280025-Q1 , TMS320F280025C , TMS320F280025C-Q1 , TMS320F280033 , TMS320F280034 , TMS320F280034-Q1 , TMS320F280036-Q1 , TMS320F280036C-Q1 , TMS320F280037 , TMS320F280037-Q1 , TMS320F280037C , TMS320F280037C-Q1 , TMS320F280038-Q1 , TMS320F280038C-Q1 , TMS320F280039 , TMS320F280039-Q1 , TMS320F280039C , TMS320F280039C-Q1

 

  1.   Abstract
  2.   Trademarks
  3. 1Introduction
  4. 2Theory
  5. 3Hardware
  6. 4Software
  7. 5Results
  8. 6Summary
  9. 7References

Summary

This application note covered the effects of oversampling with an ADC using software methods, and how oversampling can increase the effective number of bits (ENOB). The theoretical ENOB increases by 0.5 every time the oversampling factor is doubled. The observed ENOB increase is slightly lower due to system noise limitations. This can be further improved by adding a buffer to the ADC input and using an external VREF source. Oversampling does decrease the rate at which individual samples are read, since the oversampling takes up additional time within the control loop. There is also an increase in time to collect results from the ADC, depending on the oversampling factor.