ATXMEGA256A3U Datasheet, PDF (46/116 Pages) ATMEL Corporation – 8/16-bit Atmel XMEGA A3U Microcontroller

XMEGA A3U
The ADC has a compare function for accurate monitoring of user defined thresholds with mini-
mum software intervention required.
Figure 27-1. ADC overview
ADC0
•
•
•
ADC15
AD•C4
•
•
ADC7
Int. signals
AD•C0
•
•
ADC3
Int. signals
Internal
signals
½x - 64x
V_INP
ADC
Internal
signals
V_INN
Internal 1.00V
Internal VCC/1.6V
Internal VCC/2
AREFA
AREFB
Reference
Voltage
Compare
Register
CH0 Result
CH1 Result
CH2 Result
CH3 Result
<
>
Threshold
(Int Req)
Four inputs can be sampled within 1.5µs without any intervention by the application.
The ADC may be configured for 8- or 12-bit result, reducing the minimum conversion time (prop-
agation delay) from 3.5µs for 12-bit to 2.5µs for 8-bit result.
ADC conversion results are provided left- or right adjusted with optional ‘1’ or ‘0’ padding. This
eases calculation when the result is represented as a signed integer (signed 16-bit number).
PORTA and PORTB each has one ADC. Notation of these peripherals are ADCA and ADCB,
respectively.
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8386A–AVR–07/11