DocID17035 Rev 3

13/25

AN3147

Run and low power modes

24

4.2.1

STM8L101xx low power modes

The STM8L101xx devices feature the following main low power modes:



Wait mode: CPU stopped and peripherals kept running



Active-halt mode: CPU stopped, AWU (auto-wakeup) and IWDG (independent

watchdog) kept running if enabled.



Halt mode: CPU and peripheral clocks stopped

4.2.2

STM8L05xxx, STM8L15xxx, STM8L162xx, STM8AL31xx and

STM8AL3Lxx low power modes

STM8L05xxx, STM8L15xxx, STM8L162xx, STM8AL31xx and STM8AL3Lxx devices feature

the following main low power modes:



Wait mode: CPU clock stopped, peripherals kept running



Low power run mode: executing code is done from RAM with a low speed oscillator

(LSI or LSE); selected peripherals remain active



Low power wait mode: CPU clock stopped; selected peripherals remain active



Active-halt mode: CPU clock stopped, AWU/RTC (auto wakeup/real-time clock) and

IWDG (independent watchdog) kept running if enabled



Halt mode: everything is stopped.

Table 3. Low power mode summary

Low power

modes

Entry

Functions

Low power modes names

and consumptions

CPU Peripherals

High

speed

osc.

RTC

calendar

LSI

LSE

Flash RAM

STM8L &

STM8AL

typical

values

@ 3V/25°C

STM8L &

STM8AL

typical

values

@ 3V/85°C

Low power

run

Software

sequence

ON

Can be

enabled

OFF

ON

ON

OFF

ON

5.4 µA

6.8 µA

Low power

wait

Software

sequence

+ WFE

OFF

Can be

enabled

OFF

ON

ON

OFF

ON

3.3 µA

4.4 µA

Active-halt

w/ full RTC

HALT

OFF

ON

ON

OFF

ON

1.4 µA

Active-halt

w/ RTC

on LSI

OFF

ON

OFF

ON

0.8 µA(1)

1.2 µA

Halt

OFF

OFF OFF

ON

0.4 µA(1)

1 µ A

1. Internal reference voltage and BOR off.