ATXMEGA16A4_14 Datasheet, PDF (43/108 Pages) ATMEL Corporation – Non-volatile Program and Data Memories

XMEGA A4
26. DAC - 12-bit Digital to Analog Converter
26.1 Features
26.2 Overview
• One DAC with 12-bit resolution
• Up to 1 Msps conversion rate
• Flexible conversion range
• Multiple trigger sources
• 1 continuous output or 2 Sample and Hold (S/H) outputs
• Built-in offset and gain calibration
• High drive capabilities
• Low Power Mode
The XMEGA A4 devices feature one 12-bit, 1 Msps DAC with built-in offset and gain calibration,
see Figure 26-1 on page 43.
A DAC converts a digital value into an analog signal. The DAC may use an internal 1.0 voltage
as the upper limit for conversion, but it is also possible to use the supply voltage or any applied
voltage in-between. The external reference input is shared with the ADC reference input.
Figure 26-1. DAC overview
Configuration
Reference selection
Channel A
Register
Channel B
Register
DAC
Channel A
Channel B
Event
Trigger
The DAC has one continuous output with high drive capabilities for both resistive and capacitive
loads. It is also possible to split the continuous time channel into two Sample and Hold (S/H)
channels, each with separate data conversion registers.
A DAC conversion may be started from the application software by writing the data conversion
registers. The DAC can also be configured to do conversions triggered by the Event System to
have regular timing, independent of the application software. DMA may be used for transferring
data from memory locations to DAC data registers.
The DAC has a built-in calibration system to reduce offset and gain error when loading with a
calibration value from software.
PORTB has one DAC. Notation of this peripheral is DACB.
8069R–AVR–06/2013
43
Not recommended for new designs -
Use XMEGA A4U series