Table 344. Sar Adc Alternate References - STMicroelectronics SPC572L series Reference Manual

Analog-to-digital converter (ADC) configuration
External
Pins
Trigger source selection for each SAR ADC is given in the SIUL2 chapter of this document.
34.2.2.6 SAR ADC alternate reference
The SAR ADCs support connection to more than one conversion reference. The alternate
references are muxed with analog input pins on SPC572Lx. The analog input pins used as
alternate references to the respective SAR ADCs are given in
To meet safety requirements, the reference for specific SAR analog inputs cannot be
changed. For SPC572Lx, these are SARB channels 4–7 and 35, and all other SAR0 and
SAR4 analog inputs. For these SAR ADC instances that do not enable an alternate
reference, ICDRn[REFSEL] is a read-only bit. There is no option to connect these pins as
analog references for the device for safety considerations.
Alternate reference selection is enabled only for the following channels, for which
ICDRn[REFSEL] is a read-write bit:
SARB channels (0–8, 16–17, 24, 36–39, 52–53, 56–61): see
register
34.2.2.7 SAR absolute voltage reference
SPC572Lx provides an internal, absolute voltage reference that can be read by SARB. The
ADC conversion channel number for the absolute reference, ADC Bandgap Reference, is
given in Table
704/2058
Figure 309. SAR ADC input trigger diagram
.
.
7
.
channel
outputs
GTM

Table 344. SAR ADC alternate references

SAR ADC
SARB
definitions.
346.
DocID027809 Rev 4
System Integration
injected conversion
normal conversion
injected conversion
normal conversion
injected conversion
normal conversion
AN[16]
start
signal
Digital
I/F
Digital
I/F
Digital
I/F
Table 344.
Alternate reference pin
Table 350: SAR ADCB
RM0400
SARB
SAR0
SAR4