TI takes low-power MCU line to 32-bit with an ARM core
The original MSP designation, TI recalls, stood for “mixed-signal microcontroller” and the 32-bit parts follow that path with features such as a 14-bit ADC. TI has developed a customised process at 90 nm geometry, that it runs in its own fabs, to provide the performance/power characteristics it needs for these MCUs. The process has been characterised to run in an external fab if the need for a full second source arises.
The devices run at clock speeds of up to 48 MHz, achieving 95 µA/MHz in active power and 850 nA in standby power, and returning 3.41 on the EEMBC CoreMark benchmark. TI says this is the lowest power Cortex-M4F MCU implementation available anywhere; when deciding on a 32-bit core, the company says it considered a Cortex-M0+ but quickly determined that its process allowed the use of the higher-performance M4F with no power penalty. The MSP432 MCUs also deliver a best-in-class ULPBench (also by EEMBC) score of 167.4 – outperforming all other Cortex-M3 and -M4F MCUs, TI says.
TI uses is own flash memory on the chips, organised in banks that allow operate-from-one/erase-another. The process does not support FRAM, and TI’s FRAM MCUs continue on their own, separate path. As part of its support, TI provides a driver library – customer profiles for its prior devices showed this to be sufficiently popular that the company opted to place it in ROM on the 432 series, providing faster run-time operation.
An integrated DC/DC optimises power efficiency at high-speed operation, while an integrated LDO reduces overall system cost and design complexity. The 14-bit ADC operates at 1 Msample/sec and achieves and ENOB (effective number of bit) of 13.2: it consumes 375 µA at 1Msps. MSP432 MCUs include a selectable RAM retention feature that provides dedicated power to each of the eight RAM banks needed for an operation, so overall system power can be trimmed by 30 nA per bank. MSP432 MCUs can also operate as low as 1.62V and as high as 3.7V with full-speed operation to lower overall system power (but operation direct from a single lithium cell is not intended). Declared product plans include additional analogue functions and up to 2MB flash memory; the first part in the series includes 256 kB flash and 64 kB RAM. An advanced encryption standard (AES) 256 hardware encryption accelerator enables developers to secure their device and data, while IP protection features on MSP432 MCUs ensure data and code security.
The introduction does not in any sense, TI adds, replace the MSP430 line; “We will continue to invest heavily in the 16-bit line, and the market for the 16-bit devices is still growing.” If you wish to move from the 430 to the 432 line, as long as your code is in standard C, the tools will make it a simple operation; standard ARM tool sets from Keil and IAR Systems will support the parts.
You can start evaluating MSP432 MCUs with a target board (MSP-TS432PZ100) or a low-cost LaunchPad rapid prototyping kit (MSP-EXP432P401R) with on-board emulation. Developers can expand their MSP432 LaunchPad kit evaluation with a full suite of stackable BoosterPacks, including the low-power SimpleLink Wi-Fi CC3100 BoosterPack.
A tools innovation is TI’s Cloud Development Ecosystem, which includes compile-in-the-cloud. It helps developers get started faster by allowing them to access their products, documentation, software and even integrated development environment (IDE) all from the web. MSP432 MCUs support multiple real-time operating system (RTOS) options, including TI-RTOS, FreeRTOS and Micrium uC/OS.
Further features include;
– Code, register and low-power peripheral compatibility between MSP430 and MSP432 portfolios enables developers to use existing code and port code between 16- and 32-bit devices.
– EnergyTrace+ technology and ULP Advisor software monitor power consumption in real time with +2% accuracy.
– A power-optimised MSPWare software suite includes libraries, code examples, documentation and hardware tools for 16- and 32-bit MSP MCUs and can be accessed online with TI’s Resource Explorer or Code Composer Studio (CCS) IDE. Additional support through IAR Embedded WorkBench and ARM Keil MDK IDEs.
– Open-source Energia supports rapid prototyping on the MSP432 LaunchPad kit. Immediately leverage a broad code base for rapid firmware development by easily importing libraries for cloud connectivity, sensors, and displays.
– Developers can create IoT-connected designs with more flexibility and memory, higher performance, integrated analogue and compatible Wi-Fi, Bluetooth Smart and Sub-1 GHz wireless connectivity solutions.
The MSP432P401RIPZ MCU is available for immediate sampling; devices will be available with a variety of features, packages sizes and up to 256 kB flash starting at $2.15 (1000). Developers can start designing with MSP432 MCUs using the MSP-EXP432P401R LaunchPad kit for $12.99 or the MSP-TS432PZ100 target board for $89.
Texas Instruments; https://www.ti.com/ep-mcu-msp-432-pr-lp1-en