Internal Voltage Reference (Vrefint ); Dac (Digital-To-Analog Converter); Operational Amplifier - STMicroelectronics STM32L151RE Manual

Functional overview
stored by ST in the system memory area, accessible in read-only mode. See
Temperature sensor calibration
3.10.2 Internal voltage reference (V
The internal voltage reference (V
ADC and Comparators. V
enables accurate monitoring of the V
available for ADC). The precise voltage of V
ST during production test and stored in the system memory area. It is accessible in read-
only mode. See
3.11

DAC (digital-to-analog converter)

The two 12-bit buffered DAC channels can be used to convert two digital signals into two
analog voltage signal outputs. The chosen design structure is composed of integrated
resistor strings and an amplifier in non-inverting configuration.
This dual digital Interface supports the following features:
•
Two DAC converters: one for each output channel
•
8-bit or 12-bit monotonic output
•
Left or right data alignment in 12-bit mode
•
Synchronized update capability
•
Noise-wave generation
•
Triangular-wave generation
•
Dual DAC channels, independent or simultaneous conversions
•
DMA capability for each channel (including the underrun interrupt)
•
External triggers for conversion
•
Input reference voltage V
Eight DAC trigger inputs are used in the STM32L151xE and STM32L152xE devices. The
DAC channels are triggered through the timer update outputs that are also connected to
different DMA channels.
3.12

Operational amplifier

The STM32L151xE and STM32L152xE devices embed two operational amplifiers with
external or internal follower routing capability (or even amplifier and filter capability with
external components). When one operational amplifier is selected, one external ADC
channel is used to enable output measurement.
The operational amplifiers feature:
• Low input bias current
•
Low offset voltage
• Low-power mode
•
Rail-to-rail input
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values.
REFINT
REFINT
is internally connected to the ADC_IN17 input channel. It
REFINT
DD
Table 15: Embedded internal reference voltage calibration
REF+
DocID025433 Rev 8
STM32L151xE STM32L152xE
)
) provides a stable (bandgap) voltage output for the
value (when no external voltage, VREF+, is
is individually measured for each part by
REFINT
Table 60:
values.