Datasheet

Functional overview STM32F303xB STM32F303xC
20/133 DocID023353 Rev 7
3.12.3 V
BAT
battery voltage monitoring
This embedded hardware feature allows the application to measure the V
BAT
battery voltage
using the internal ADC channel ADC1_IN17. As the V
BAT
voltage may be higher than V
DDA
,
and thus outside the ADC input range, the V
BAT
pin is internally connected to a bridge
divider by 2. As a consequence, the converted digital value is half the V
BAT
voltage.
3.12.4 OPAMP reference voltage (VREFOPAMP)
Every OPAMP reference voltage can be measured using a corresponding ADC internal
channel: VREFOPAMP1 connected to ADC1 channel 15, VREFOPAMP2 connected to
ADC2 channel 17, VREFOPAMP3 connected to ADC3 channel 17, VREFOPAMP4
connected to ADC4 channel 17.
3.13 Digital-to-analog converter (DAC)
Two 12-bit buffered DAC channels can be used to convert digital signals into analog voltage
signal outputs. The chosen design structure is composed of integrated resistor strings and
an amplifier in inverting configuration.
This digital interface supports the following features:
 Two DAC output channels
 8-bit or 10-bit monotonic output
 Left or right data alignment in 12-bit mode
 Synchronized update capability
 Noise-wave generation
 Triangular-wave generation
 Dual DAC channel independent or simultaneous conversions
 DMA capability (for each channel)
 External triggers for conversion
 Input voltage reference VREF+
3.14 Operational amplifier (OPAMP)
The STM32F303xB/STM32F303xC embeds four operational amplifiers with external or
internal follower routing and PGA capability (or even amplifier and filter capability with
external components). When an operational amplifier is selected, an external ADC channel
is used to enable output measurement.
The operational amplifier features:
 8.2 MHz bandwidth
 0.5 mA output capability
 Rail-to-rail input/output
 In PGA mode, the gain can be programmed to be 2, 4, 8 or 16.