ARM Cortex M4, a power efficient 32-bit processor core with DSP capabilities, which occupy less than a square-mm space on silicon die in some of the advanced nodes, gives chip designers the advantage of space and power efficiency while designing chips for mobile and embedded systems.
ST Microelectronics has leveraged both of its chip fabrication capabilities as well as chip design capabilities to come up with a family of microcontroller chips based on ARM Cortex M4 for high performance applications. ST Microelectronics has enhanced the performance ARM Cortex M4 based MCU to operate at 180MHz and deliver 225DMIPS (Dhrystone MIPS) and 608 CoreMark (EEMBC Caremark benchmark) scores using industry-standard performance metrics by using its adaptive real-time accelerator (ART Accelerator) allowing zero-wait execution from Flash. This is the highest performance ARM Cortex M4 based MCU presently available in the market.
STM32F429/439 series offer SDRAM memory interface and has on-chip LCD Controller to support TFT displays of resolution 800*600. The final physical chip size measuring 3x3mm is also small enough to support many handheld portable systems.
What is more interesting than the technology is the range of applications this device can be used for. STM32F439 can be used as coprocessor in advanced smart phones to handle motion data from the accelerometer, gyroscope, and compass MEMS sensors. Devices and systems which rely on smart phone's motion sensor inputs can access motion data directly from the coprocessor instead of main processor.
The most interesting application suggested by Frank Martins, MCU Marketing and Applications Manager, South Asia Region, ST microelectronics, is the smart watch powered by STM32F439 chip. STM32F439 is also very much suitable for consumer medical electronic devices.
As usual, ST microelectronics is providing design engineer with range of tools, IP libraries, development kits in India as well as other parts of world, so that the developer can buy/access the required tools easily. STM32F4 development ecosystem includes STM32 Discovery Kits and full-featured STM32F4x9 evaluation boards, software solutions like STM32-JAVA Java and the STemWin free graphical stack based on the Segger emWin solution, which leverages the LCD-TFT controller and dedicated Chrom-ART accelerator of the STM32F4x7/4x9 microcontrollers. Advanced audio IP including codecs and sound-processing algorithms is also available from ST. Extended solutions from ST partners include IAR Experiment! Magnetometer and game-controller kits, as well as the Raisonance EvoPrimer ecosystem. Standard development environments are supported from Atollic, IAR, Keil/ARM, Raisonance, and Tasking. Boards will be orderable from distributors or ST’s e-STore before the end of October 2013.
The STM32F427/437 series is also entering full production, upgraded with the 180MHz core, dual-bank memory, and other features of the STM32F429/439 excluding the TFT-LCD controller.
Also entering volume production is the STM32F401 microcontroller announced in April 2013. The device balances high performance (105 DMIPS and 285 CoreMark, and zero-wait Flash execution with the ART Accelerator), power efficiency and high feature integration in packages as small as 3x3mm.
Below is the further interesting technical data shared by ST on this family:
All of the STM32F4 devices are extremely power efficient, helping simplify design and extend battery life in portable applications. ST’s advanced 90nm process and advanced production and design techniques minimize the current drawn in all active and power-saving modes.
STM32F427/37 and STM32F429/39 devices consume as little as 260µA/MHz (typical) at 180MHz and 100μA (typical) in STOP mode (which is three times lower than the STOP mode consumption of previous STM32F4 devices). The STM32F401 entry-level high-performance microcontroller achieves 137µA/MHz at 84MHz and just 11µA typical in STOP mode.
The 1Mbyte or 2Mbyte dual-bank Flash available in the STM32F429/39 series and now also the STM32F427/37 allows read-while-write operations, allowing extra flexibility for application designers and helping protect memory contents. An application can run normally while an update is downloaded to be applied safely at a later time.
Both series also include an external memory interface for SDRAM modules, featuring a 32-bit wide data bus and operation up to 90MHz. This allows embedded-system designers to use SDRAM as a cost-effective and high-performing alternative to SRAM external memories.
ST’s Chrom-ART Accelerator featured in the STM32F429/39 and STM32F427/37 series integrates a hardware block for faster graphics processing for either TFT,serial or parallel display interfaces. It enables richer graphics and boosts application performance by offloading the Cortex-M4 core and performing operations such as pixel-format conversion at twice the speed of software.
In addition, the I2S TDM (Inter-IC Sound Time Division Multiplex) interface provides state-of-the-art digital audio connectivity allowing multi-channel audio designs.
The STM32F429/39 and STM32F427/37 series also feature advanced memory protection, which allows restricted execution-only access to Flash memory sectors thereby helping software-IP providers, silicon providers and customers protect firmware against illegal copying.