CD00001237 Datasheet, PDF (33/105 Pages) STMicroelectronics – 8-bit MCUs with A/D converter

ST6215C ST6225C
7 POWER SAVING MODES
7.1 INTRODUCTION
To give a large measure of flexibility to the applica-
tion in terms of power consumption, two main pow-
er saving modes are implemented in the ST6 (see
Figure 19).
In addition, the Low Frequency Auxiliary Oscillator
(LFAO) can be used instead of the main oscillator
to reduce power consumption in RUN and WAIT
modes.
After a RESET the normal operating mode is se-
lected by default (RUN mode). This mode drives
the device (CPU and embedded peripherals) by
means of a master clock which is based on the
main oscillator frequency.
From Run mode, the different power saving
modes may be selected by calling the specific ST6
software instruction or for the LFAO by setting the
relevant register bit. For more information on the
LFAO, please refer to the Clock chapter.
Figure 19. Power Saving Mode Transitions
High
RUN
LFAO
WAIT
STOP
Low
POWER CONSUMPTION
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