Dual Combined Regular/Injected Simultaneous Mode; Description; Example Of Application; Dual Combined: Injected Simultaneous + Interleaved Mode - ST STM32 Application Note

Dual modes
2.5

Dual combined regular/injected simultaneous mode

2.5.1

Description

The dual combined regular/injected simultaneous ADC mode is a regular simultaneous
mode that allows injection. The injected channels are also converted simultaneously.
In this mode, you should convert sequences with the same length or ensure that the interval
between triggers is longer than the longest of the 2 sequences. Otherwise, the ADC with the
shortest sequence may restart while the ADC with the longest sequence is completing the
previous conversions.
Note: An example of firmware is provided with this application note:
Dual_Combined_Reg_Inj_Sumultaneous. The example uses two methods: DMA and
interrupts. To select either method, simply comment or uncomment #define
USE_DMA_Transfer in the main.c file.

Figure 12. Dual combined regular/injected simultaneous mode

2.5.2

Example of application

The dual combined (regular/injected) simultaneous mode can be used to read 3-phase
currents at definite times. This mode is interesting when you read the currents of two of the
phases and you determine the current of the third phase by extrapolation since there is a
relationship between the currents of the 3 phases.
2.6

Dual combined: injected simultaneous + interleaved mode

2.6.1

Description

This mode is the combination of the dual interleaved mode (fast or slow) and the dual
injected simultaneous mode. When the regular channel is triggered, the dual interleaved
conversion starts: ADC2 makes the first conversion, then ADC1 converts the channel and
so on. When the injected channel is triggered, it interrupts the interleaved channel
conversion and the two ADCs (ADC1 and ADC2) start converting the group of injected
channels. When the two ADCs finish the injected conversion, they resume the conversion of
the channel configured in interleaved mode.
14/18 Doc ID 16840 Rev 1
AN3116