at91sam9g20-cu ATMEL Corporation, at91sam9g20-cu Datasheet - Page 742

• Manufacturer Part Number: at91sam9g20-cu
• Description: At91 Arm Thumb Microcontrollers
• Manufacturer: ATMEL Corporation

40.3
Table 40-1.
40.4
40.4.1
40.4.2
40.4.3
40.4.4
40.4.5
40.4.6
742
Pin Name
VDDANA
ADVREF
AD0 - AD3
ADTRG
Signal Description
Product Dependencies
AT91SAM9G20 Preliminary
Power Management
Interrupt Sources
Analog Inputs
I/O Lines
Timer Triggers
Conversion Performances
ADC Pin Description
The ADC is automatically clocked after the first conversion in Normal Mode. In Sleep Mode, the
ADC clock is automatically stopped after each conversion. As the logic is small and the ADC cell
can be put into Sleep Mode, the Power Management Controller has no effect on the ADC
behavior.
The ADC interrupt line is connected on one of the internal sources of the Advanced Interrupt
Controller. Using the ADC interrupt requires the AIC to be programmed first.
The analog input pins can be multiplexed with PIO lines. In this case, the assignment of the ADC
input is automatically done as soon as the corresponding channel is enabled by writing the reg-
ister ADC_CHER. By default, after reset, the PIO line is configured as input with its pull-up
enabled and the ADC input is connected to the GND.
The pin ADTRG may be shared with other peripheral functions through the PIO Controller. In
this case, the PIO Controller should be set accordingly to assign the pin ADTRG to the ADC
function.
Timer Counters may or may not be used as hardware triggers depending on user requirements.
Thus, some or all of the timer counters may be non-connected.
For performance and electrical characteristics of the ADC, see the DC Characteristics section.
Description
Analog power supply
Reference voltage
Analog input channels
External trigger
6384B–ATARM–15-Dec-08