The power sipping 32-bit EFM32 Gecko micro from Energy Micro just got bigger. The latest Giant Gecko (Fig. 1) collection of ARM Cortex-M3-based chips have flash memory capacities up to 1Mbyte and up to 128 Kbytes of SRAM. They also have 12 Mbit/s USB host and OTG support plus 4x40 segment LCD display options. The 128/256-bit AES hardware acceleration streamlines encryption support.
Energy Micro's Giant Gecko (Fig. 2) targets applications that can take advantage of its low power technology. It uses only 180µA/MHz and its 32-bit architecture can allow more computational performance than 8- or 16-bit platforms. Its shut off current draw is only 20nA while its deep sleep mode with a 2µsec wake up time is 900nA. In theory, a low power design with a 1s cycle time running on a single 3V CR2032 lithium battery could last more than a decade.
The peripheral reflex system allows peripherals to be linked together so they can operate without processor intervention. This includes operation while the processor is using one of the sleep modes. Couple with this with a set of specially designed, low power peripherals like the 100nA UART running at 9600 baud and applications can cost along while sipping from the battery. The chips also have higher performance peripherals that draw more power allowing developers to choose performance when necessary.
The other key component in the mix are the development tools. Choosing low power modes and using low power peripherals is great but guestimates are not what is neeeded when shipping a product. Energy Micro recognizes that the right tools are required and starts with its Gecko development platform (Fig. 3). The LCD display is not just the application. It is a real time, power feedback mechanism powered by its own microcontroller. The processor under test comes on a module that plugs into the development board.
The development hardware is tied in with the energyAware Profiler (Fig. 4). The profiler provides realtime feedback that is linked directly to the source code. Developers will be able to see what sections of code is using the most and least amount of power.
The chips are available in a range of packages from 64-pin QFN to 112 ball BGAs. Pricing starts at $2.50.