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XMEGA B3 [DATASHEET]
8074D–AVR–08/2013
29.
ADC – 12-bit Analog to Digital Converter
29.1
Features
One Analog to Digital Converters (ADC)
12-bit resolution
Up to 300 thousand samples per second
Down to 2.3s conversion time with 8-bit resolution
Down to 3.35s conversion time with 12-bit resolution
Differential and single-ended input
Up to 16 single-ended inputs
16x4 differential inputs without gain
16x4 differential input with gain
Built-in differential gain stage
1/2x, 1x, 2x, 4x, 8x, 16x, 32x, and 64x gain options
Single, continuous and scan conversion options
Three internal inputs
Internal temperature sensor
V
CC voltage divided by 10
1.1V bandgap voltage
Internal and external reference options
Compare function for accurate monitoring of user defined thresholds
Optional event triggered conversion for accurate timing
Optional DMA transfer of conversion results
Optional interrupt/event on compare result
29.2
Overview
The ADC converts analog signals to digital values. The ADC has 12-bit resolution and is capable of converting up to 300
thousand samples per second (KSPS). The input selection is flexible, and both single-ended and differential
measurements can be done. For differential measurements, an optional gain stage is available to increase the dynamic
range. In addition, several internal signal inputs are available. The ADC can provide both signed and unsigned results.
The ADC measurements can either be started by application software or an incoming event from another peripheral in
the device. The ADC measurements can be started with predictable timing, and without software intervention. It is
possible to use DMA to move ADC results directly to memory or peripherals when conversions are done.
Both internal and external reference voltages can be used. An integrated temperature sensor is available for use with the
ADC. The output from the V
CC/10 and the bandgap voltage can also be measured by the ADC.
The ADC has a compare function for accurate monitoring of user defined thresholds with minimum software intervention
required.