DocID023897 Rev 1

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Comparison between ADC F1 family and F3 family

Differential mode

To configure the ADC channels to differential mode, first disable the ADC (ADCAL=0,

JADSTART=0, JADSTP=0, ADSTART=0, ADSTP=0, ADDIS=0 and ADEN=0). Select

differential input mode by programming DIFSEL[15:1] in the ADC_DIFSEL register.

Note:

If ADC analog input Channel-i is configured in differential, DIFSEL[i] should be set to ’1’.

The analog voltage to be converted for channel “i” is the difference between the external

voltage ADC_INi (positive input) and ADC_INi+1 (negative input).

1.1.3

Auto-Delay controller

The Auto delayed-conversions are useful to simplify the software as well as to optimize

performance of applications clocked at low frequency where there would be a risk to

encounter an ADC overrun. When the autodelay feature is enabled (AUTDLY=1), a new

conversion can start only if all the previous data of the same group has been treated:

•

For the regular conversion group, once the ADC_DR register is read or the EOC flag is

cleared.

•

For the injected conversion group, once the JEOCS is cleared.

1.2

Difference between STM32ADC F1 and F3 family

The STM32F1 family and STM32F3 family embed the same type of the ADC, the

successive approximation register (SAR) ADC.

But there are some difference in term of features, the following table present a comparison

between the two ADCs.

Table 2. ADC F1 and ADC F3 families comparison

Feature

ADC F1 family

ADC F3 family

Max sampling rate

1 Msps

5 Msps

Resolution

12 bits

6/8/10/12 bits

Input range

ADC Clock

AHB clock

AHB clock / PLL clock

Input mode

Single-ended

Single-ended and differential

Number of channels

16 single-ended inputs

15 single ended/ differential inputs

+ 3 internal single-ended channels

Analog watchdog

1 AWDG

3 AWGD

Trigger sources for regular

conversion

– Software

– Embedded timers

– External events

– Software

– Embedded timers

– External events

Trigger sources for injected

conversion

– Software

– Embedded timers

– External events

– Software

– Embedded timers

– External events

Number of instances

1 or 2

4

Dual mode

Yes

Yes