33.4.2.1 Operation Modes

The ADC supports several modes, each of which allows both single-ended and differential conversions.

The following operation modes are available:
  • Single mode - One conversion per trigger
  • Series Accumulation mode - One conversion per trigger, with an accumulation of n samples
  • Burst Accumulation mode - A burst of n samples accumulated as quickly as possible after a single trigger. The SAMPRDY interrupt/event occurs after every conversion, and the RESRDY interrupt/event occurs after n conversions.

Series and Burst Accumulation modes can be configured with or without scaling of the accumulated result. The Sample Number bit field in the Control D register (CTRLD.SAMPNUM) controls how many samples are accumulated. The accumulator is always reset to ‘0’ when a new Series or Burst accumulation is started.

The Series and Burst Accumulation modes can be used for oversampling to achieve up to five bits higher resolution, given suitable input signal, operating environment, and sampling frequency. Increasing the resolution by N bits can be achieved by accumulating 4N samples and dividing the accumulated result by 2N. The CTRLD.SAMPNUM bit field can be configured for up to 45 = 1024 samples, resulting in up to 18-bit resolution (assuming 13-bit resolution is enabled).