Power consumption comparison

AN4635

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DocID027290 Rev 1

6.11

Voltage regulator settings

Setting lower core voltage level is an easy and straightforward way to save energy.

In Figure 12 it is demonstrated that even with HSI clock the run mode can be significantly

more current-hungry just by changing the voltage.

Note that the setting has little or no influence on idle mode.

Figure 12. Comparison between voltage regulator settings

Baud rate

57600

SW used

Interrupt operation (Com IT)

Table 13. Configurations - HSI vs. MSI (continued)

Black

Red

Table 14. Configurations - Voltage regulator settings

Curve in Figure 12

Red

Black

Green

Idle mode between

transmissions

Sleep

JTAG interface

OFF

Current average

over phases 2, 3 and 4

70.31 µA

71.19 µA

71.84 µA

Clock

4 MHz HSI

Voltage regulator

Range 3

Range 2

Range 1

AHB/APB ratio

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