STMicroelectronics has reduced the power required to operate a sophisticated 32-bit microcontroller to a new low level with the introduction of its STM32L4 series of MCUs.
The first two microcontrollers in the series, the STM32L476 and STM32L486, feature an 80MHz ARM® Cortex®-M4 core with DSP and floating-point unit. This low-power core is combined in the STM32L4 devices with the ST ART Accelerator™, which provides for zero-wait execution of instructions from Flash.
This combination of low-power technologies enables the devices to achieve up to 100DMIPS while drawing just 100μA/MHz. Up to 1Mbyte of dual-bank Flash and 128kbytes of SRAM support sophisticated applications and read-while-write capability.
The ultra-low power consumption of these new MCUs has been verified in independent testing against the standard EEMBC™ ULPBench® benchmark: in tests comparing the efficiency of various ultra-low-power microcontrollers, the STM32L476 and STM32L486 scored 123, the best in the industry.
Other low-power technologies implemented by ST in the STM32L4 microcontrollers include:
• dynamic voltage scaling to balance power consumption with processing demand
• the FlexPowerControl architecture
• seven power-management modes with sub-mode options. These include Stop, Stand-by, and Shut-down modes, in which current is as low as 30nA
• Batch acquisition mode for efficient data exchange with communication peripherals while in low-power mode
The STM32L476 and STM32L486 also feature three 12-bit ADCs operating at up to 5Msamples/s. Hardware oversampling enables the devices to achieve an upscaled 16-bit resolution.
The STM32L4 Discovery Kit combines an STM32L476 MCU with an LCD screen, LEDs, audio DAC, microphone, gyroscope and compass, joystick and connectivity features. It includes an embedded ammeter which measures the MCU’s power consumption in low-power modes.
Orderable Part Number: STM32L476G-DISCO