Rainbow Electronics AT91CAP9S250A - Manual (Page 941)

941
6264A–CAP–21-May-07
AT91CAP9S500A/AT91CAP9S250A
46. Analog-to-Digital Converter (ADC)
46.1 Description
The ADC is based on a Successive Approximation Register (SAR) 10-bit Analog-to-Digital Con-
verter (ADC). It also integrates an 8-to-1 analog multiplexer, making possible the analog-to-
digital conversions of 8
analog lines. The conversions extend from 0V to ADVREF.
The ADC supports an 8-bit or 10-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 out-
put(s) are configurable.
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.
Finally, the user can configure ADC timings, such as Startup Time and Sample & Hold Time.
46.2 Block Diagram
Figure 46-1. Analog-to-Digital Converter Block Diagram
ADC Interrupt
ADC
ADTRG
VDDANA
ADVREF
GND
Trigger
Selection
Control
Logic
Successive
Approximation
Register
Analog-to-Digital
Converter
Timer
Counter
Channels
User
Interface
AIC
Peripheral Bridge
APB
PDC
ASB
Dedicated
Analog
Inputs
Analog Inputs
Multiplexed
with I/O lines
AD-
AD-
AD-
PIO
AD-
AD-
AD-