6.5.9.1 ADC
An ADC is a peripheral that converts a continuous analog voltage to a discrete digital number. The ADC module features 12-bit conversion resolution and supports 20 input channels plus an internal temperature sensor. Four buffered sample sequencers allow rapid sampling of up to 20 analog input sources without controller intervention. Each sample sequencer provides flexible programming with fully configurable input source, trigger events, interrupt generation, and sequencer priority. Each ADC module has a digital comparator function that lets the conversion value be sent to a comparison unit that provides eight digital comparators.
Both ADC modules support the following features:
- 20 shared analog input channels
- 12-bit precision ADC
- Single-ended and differential-input configurations
- On-chip internal temperature sensor
- Maximum sample rate of two million samples/second
- Optional, programmable phase delay
- Sample and hold window programmability
- Four programmable sample conversion sequencers from one to eight entries long, with corresponding conversion result FIFOs
- Flexible trigger control
- Controller (software)
- Timers
- Analog comparators
- PWM
- GPIO
- Hardware averaging of up to 64 samples
- Eight digital comparators
- Converter uses two external reference signals (VREFA+ and VREFA–) or VDDA and GNDA as the voltage reference
- Power and ground for the analog circuitry is separate from the digital power and ground
- Efficient transfers using µDMA
- Dedicated channel for each sample sequencer
- ADC module uses burst requests for DMA
- Global Alternate Clock (ALTCLK) resource or System Clock (SYSCLK) can be used to generate ADC clock.