ST intros STM32L ultra-low-power Cortex‑M3 devices

STMicroelectronics has introduced the STM32L advanced ultra-low-power Cortex-M3 based MCU platform.

Built on cutting-edge proprietary process – robustness, it is part of a wide 32-bit product portfolio. The MCU platform is based on the just-enough energy concept and has an all inclusive package applications.

STM32L 32- to 128-Kbyte products are entering full production in the second half of March 2011. It is part of the industry’s largest ARM Cortex-M 32-bit microcontroller family with six STM32 families. STMicroelectronics is developing the STM32L portfolio up to 384 Kbytes of embedded memory. The STM32L is also Continua ready for its USB peripheral driver.

STM32L’s robustness has been derived from an automotive qualified process. It is all inclusive for ultra-low-power applications, and comes with hardware integrated features and software library packages. STM32L also has a ‘just-enough energy concept’, which includes undervolting, user controlled and an innovative architecture, all of this for less than 1 µA.

ST’s ultra-low-power EnergyLite platform features ST’s 130nm ultra-low-leakage process technology. It makes use of shared technology, architecture and peripherals. The company’s ultra-low-power portfolio for 2011 will be in production second half of March 2011. Many others will also be in production in the second half of April 2011. In fact, there will be over 100 part numbers from 4- to 384-Kbyte flash, and from 20 to 144 pins.

STM32L is based on ultra-low-power architecture, which is all inclusive for ultra low power applications. It also features ultra-low voltage, with power supply down to 1.8 V with BOR and also down to 1.65 V without BOR.The analog functional can be down to 1.8 V and the reprogramming capability can be down to 1.65 V.

STM32L is also flexible and secure, featuring +/- 0.5 percent internal clock accuracy when trimmed by RTC oscillator. It has up to five clock sources and has the MSI to achieve very low power consumption at seven low frequencies.

It also feattures dynamic voltage scaling in Run mode. The voltage scaling optimizes the product efficiency. User selects a mode (voltage scaling) according to external VDD supply, DMIPS performance required and maximum power consumption. It features the energy saving mode as well, down to 171 µA/DMIPS from Flash in Run mode.

Extension of STM32L portfolio is envisaged as following:
* Ultra-low power available from 32-Kbyte to up to 384-Kbyte of embedded Flash.
* New devices in development up to 384 Kbytes (256-Kbyte and 384-Kbyte sales types).
* Ultra-low power consumption maintained even with higher memory density.

New features benefiting applications include 32-bit timer, additional communication peripherals, external memory interface, more embedded data EEPROM, 384-Kbyte Flash with two banks for safe in-application software upgrading enabling read while write, additional analog inputs (up to 40 channels), up to 39 touch-sensing analog channels, and three operational amplifiers with ultra-low leakage inputs. All of this on 128-bit hardware encryption AES-128.

It also features an MPU to protect specific code or data and a multi-speed internal oscillator (MSI ) for low-frequency running at up to 4 MHz with low consumption. Voltage scaling is done to dynamically optimize consumption. There are six low-power modes down to 300 nA in Standby mode.

Some leading STM32L applications are in industrial, consumer, and health and fitness. The STM32 is said to be a good fit for portable medical devices. The STM32L series makes use of Continua for PHDC-USB healthcare device class. Hardware tools offer include an evaluation board for full product feature evaluation.

The STM32L Discovery low-cost evaluation kit is the cheapest and quickest way to discover the STM32L. It is meant for fast evaluation or prototyping at less than 10 €. The kit will be available in April 2011. There is also a large choice of development IDE solutions.

Software libraries that speeden up the time to market include the STM32 standard peripheral libraries, including C source code for easy implementation of all STM32 peripherals in any application. The STM32L touch-sensing library is meant for free source code touch-sensing library for easy implementation. The Class B: IEC 60335-1 approved self-diagnostic routines is for ST’s self-test-library software modules that have been approved by the VDE.

STMTouch firmware library includes the NRE/royalty-free source code solution to provide surface capacitive touch-sensing capabilities for STM8L and STM32L MCUs. There is easy integration of keys, sliders and wheels to replace conventional electromechanical switches in human interfaces

The library offers a complete solution with acquisition, post processing and API layers, debounce filtering, calibration functions and environment change system (ECS). The library also features multi-function capability to combine capacitive sensing functions with traditional MCU features (including communication, LED control, beeper, LCD control).