AT32F421
Series Reference Manual
2022.11.11
Page 306
Rev 2.02
18
Analog-to-digital converter (ADC)
18.1 ADC introduction
The ADC is a peripheral that converts an analog input signal into a 12-bit digital signal. Its sampling
rate is as high as 2 MSPS. It has up to 18 channels for sampling and conversion.
18.2 ADC main features
In terms of analog:
12-bit configurable resolution
Self-calibration time: 154 ADC clock cycles
ADC conversion time
ADC conversion time is 0.5 μs at 28 MHz (When the system clock is 120 MHz, ADC conversion
time is 0.7 μs at 20 MHz)
ADC power supply: Refer to the data sheet for more information
ADC input range: V
REF-
≤
V
IN
≤
V
REF+
In terms of digital control:
Regular channels and preempted channels with different priority
Regular channels and preempted channels both have their own trigger detection circuit
Each channel can independently define its own sampling time
Conversion sequence management mechanism supports multiple-channel conversion
Optional data alignment
Programmable voltage monitor threshold
Regular channels with DMA transfer support
Interrupt generation at one of the following events:
―
End of the conversion of preempted channels
―
End of the conversion of regular channels
―
Voltage outside the programmed threshold
18.3 ADC structure
shows the block diagram of ADC1.