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CMS80F731x Reference Manual
23.
Analog-to-digital Converter (ADC)
23.1 Overview
An analog-to-digital converter (ADC) converts an analog input signal into a 12-bit binary number representing the signal, as
shown in the ADC block diagram below.
The port analog input signal and the internal analog signal are connected to the input of the analog-to-digital converter after
being multiplexed. The analog-to-digital converter uses successive approximation to produce a 12-bit binary result and saves
the result in the ADC result register (ADRESL and ADRSH), and the ADC can generate an interrupt after the conversion is
complete. The ADC conversion results are compared to the values of the ADC comparison data registers (ADCMPL and ADCPH),
which are stored in the ADCPO flag bits.
The ADC reference voltage is always internally generated and can be provided with avdd or by an internal ADC-LDO.
AN4
AN5
AN6
AN7
000100
000101
000110
000111
111111
ADC
ADGO
AVSS
AVDD
0=Left Aligned
1=Right Aligned
ADRESH
ADRESL
CHS<5:0>
VSS
ADEN
ADFM
DCMP
ADCMPH
ADCMPL
ADCMPO
ADC-LDO
1.2V/2V/2.4V/3V
ADC_VREF
AN3
000011
AN2
000010
AN1
000001
AN0
000000
ADC-MUX
ADC-IN
MUX
BGR
VSS
VDD
AN63