Independent A/D And D/A Converter Supply And Reference Voltage; Figure 4. Power Supply Overview - ST STM32F101 series Reference Manual

RM0008
(from 2.4 V up to V
1. V and V
DDA
5.1.1

Independent A/D and D/A converter supply and reference voltage

To improve conversion accuracy, the ADC and the DAC have an independent power supply
which can be separately filtered and shielded from noise on the PCB.
•
The ADC and DAC voltage supply input is available on a separate V
•
An isolated supply ground connection is provided on pin V
When available (according to package), V
On 100-pin and 144-pin packages
To ensure a better accuracy on low-voltage inputs and outputs, the user can connect a
separate external reference voltage on V
the full scale value, for an analog input (ADC) or output (DAC) signal. The voltage on V
can range from 2.4 V to V
On 64-pin packages and packages with less pins
The V
REF+
voltage supply (V

Figure 4. Power supply overview

(V )
V
SSA
REF-
) V
DDA REF+
V
(V )
DDA
DD
V
(V )
SSA
SS
V
SS
V
DD
V
BAT
must be connected to V
SSA
.
DDA
and V pins are not available, they are internally connected to the ADC
REF-
) and ground (V
DDA
DocID13902 Rev 15
V domain
DDA
A/D converter
D/A converter
Temp. sensor
Reset block
PLL
V domain
DD
I/O Ring
Standby circuitry
(Wakeup logic,
IWDG)
Voltage Regulator
Low voltage detector
Backup domain
LSE crystal 32K osc
BKP registers
RCC BDCR register
RTC
and V , respectively.
DD SS
must be tied to V
REF-
. V is the highest voltage, represented by
REF+ REF+
).
SSA
Power control (PWR)
1.8 V domain
Core
Memories
digital
peripherals
pin.
DDA
.
SSA
.
SSA
68/1128
REF+
80