Atmel SAM4S Series, Preliminary Data Sheet

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1033
11100B–ATARM–31-Jul-12
SAM4S Series [Preliminary]
40. Analog-to-Digital Converter (ADC)
40.1 Description
The Analog-to-Digital Converter (ADC) is based on a 12-bit Analog-to-Digital Converter (ADC)
managed by an ADC Controller. Refer to the Block Diagram:
Figure 40-1 . It also integrates a 16-
to-1 analog multiplexer, making possible the analog-to-digital conversions of 16 analog lines.
The conversions extend from 0V to ADVREF. The ADC supports an 10-bit or 12-bit resolution
mode, and conversion results are reported in a common register for all channels, as well as in a
channel-dedicated register.
Software trigger, external trigger on rising edge of the ADTRG pin or internal triggers from Timer
Counter output(s) are configurable.
The comparison circuitry allows automatic detection of values below a threshold, higher than a
threshold, in a given range or outside the range, thresholds and ranges being fully configurable.
The ADC Controller internal fault output is directly connected to PWM Fault input. This input can
be asserted by means of comparison circuitry in order to immediately put the PWM outputs in a
safe state (pure combinational path).
The ADC also integrates a Sleep Mode and a conversion sequencer and connects with a PDC
channel. These features reduce both power consumption and processor intervention.
This ADC has a selectable single-ended or fully differential input and benefits from a 2-bit pro-
grammable gain. A whole set of reference voltages is generated internally from a single external
reference voltage node that may be equal to the analog supply voltage. An external decoupling
capacitance is required for noise filtering.
A digital error correction circuit based on the multi-bit redundant signed digit (RSD) algorithm is
employed in order to reduce INL and DNL errors.
Finally, the user can configure ADC timings, such as Startup Time and Tracking Time.
40.2 Embedded Characteristics
• Up to 16 Channels, 12-bit ADC
• 10/12-bit resolution
• Up to 1 MSample/s
• Programmable conversion sequence conversion on each channel
• Integrated temperature sensor
• Automatic calibration mode
• Single ended/differential conversion
• Hardware or Software Trigger
– External Trigger Pin
– TimerPWM Event Line
– Counter Outputs (Corresponding TIOA Trigger)
• Drive of PWM Fault Input
• Programmable gain: 1, 2, 4