42.1 Overview

The Analog-to-Digital Convertor can convert up to four independent signals at a time using four separate SAR (Successive Approximation Register) ADC Modules. Each ADC module supports up to 12 bit resolution. For sample timing and conversion rates, see the ADC Electrical Specifications. Single-ended and differential measurements are supported. Signed and unsigned sampling formats are supported.

The SAR ADC0 module can support up to 16 separate external analog input channels. The SAR ADC modules 1, 2, and 3 support up to seven channels, six external and one internal channel. Internal inputs to the SAR ADC 1, 2, and 3 modules provide internal measurements for VDDCORE, Band gap temperature, and Band gap 1.2 Volt reference.

ADC measurements can be started by either application software or an incoming event from another peripheral in the device. ADC measurements can be started with predictable timing, and without software intervention.

Both internal AVDD and external VREFH reference voltages can be used (i.e., AVDD or VREFH respectively).

The ADC has a digital result compare function for accurate monitoring of user-defined thresholds, with minimum software intervention required. Hardware oversampling is also supported in the ADC’s hardware.