Very Low Active Power Consumption

Very Low Active Power Consumption
The energy friendly EFM32 microcontrollers have been designed to significantly reduce active mode power consumption. At 32 MHz and 3 V the MCU only consumes 150 µA/MHz while running real life code.


Reduced Processing Time

Reduced Processing Time
Silicon Labs has built the EFM32 microcontroller family around the 32-bit ARM® Cortex®-M processor core. The Cortex-M architecture was developed for response and power sensitive applications and is much more processing efficient than 8- and 16-bit CPUs. Tasks are therefore executed with fewer clock cycles which dramatically reduces the active period.


Very Fast Wake-up Time

Very Fast Wake-up Time
EFM32 MCUs minimize the inefficient wake-up period between deep sleep modes and active mode. This period simply cannot be neglected since low power systems continually switch between active and sleep modes. EFM32 microcontrollers have reduced the wake-up time from deep sleep to 2 µs, ensuring as little energy as possible is used before the CPU starts processing its tasks.


Ultra-low Standby Current

Ultra-low Standby Current
The EFM32 combines ultra-low power technology with clever power management to reduce energy usage in standby modes while still performing basic operations. The deep sleep mode includes RAM and CPU retention, power-on reset and brown-out detection safety features, and a real time counter while only using 900 nA. In shutoff mode the consumption is only 20 nA.


Autonomous Peripheral Operation

Autonomous Peripheral Operation
In addition to lowest active and sleep mode energy consumption, the EFM32 peripherals can operate in low energy modes without using the CPU. Using autonomous peripherals, an application can reduce power consumption while still performing very advanced tasks.


PRS - Peripheral Reflex System

Peripheral Reflex System
The peripheral reflex system in the EFM32 microcontrollers makes it possible to directly connect one peripheral to another peripheral without involving the CPU. With this system a peripheral can produce signals which other peripherals can consume and instantly react to while the CPU remains asleep.

EFM32 with 3 V power supply.
Real application from memory.
Run Mode
Sleep Mode
Deep Sleep
Stop Mode
Shutoff Mode
Current Consumption Down to 63 µA/MHz Down to 32 µA/MHz Down to 0.9 µA Down to 0.6 µA Down to 20 nA
Wake-up Time - 0 2 µs 2 µs 160 µs
Wake-up Events Any Any 32 kHZ Peripherals Async IRQ,
12C Slave
Analog Comparators
Voltage Comparators
GPIO Rising/Failing Edge
CPU (Cortex-M3/M0) On - - - -
High Frequency Peripherals Available Available - - -
Low Frequency Peripherals Available Available - - -
Asynchronous Peripherals Available Available Available Available -
Full CPU and SRAM Retention On On On On -
Power-on Reset/Brown-out Detector On On On On On