Kinetis L Challenges 16-bit MicrosJuly 16, 2012
Author: Tom Starnes, Strategy Sanity
Two companies have a lot on the line as the first microcontrollers with the ARM Cortex-M0+ CPU at their heart roll out. Built in 90nm TFS Flash technology, the Freescale Kinetis L runs the new CPU at 48MHz. It includes a stack of peripherals as well as some carefully crafted features that reduce power consumption to new lows for a 32-bit MCU. The biggest benefit of the Cortex-M0+ may be its small size, but it has powerful control capabilities as well. For the new products, Freescale paid special attention to improving energy efficiency.
The company drew on its history of control applications as well as low-power semiconductors and techniques when designing the L series. It integrated enhanced low-power modes, so just 1.7 microamps is sufficient to retain state and keep the RTC functioning while allowing the core to awaken in four microseconds.
Freescale performed a power-conservation test running a Kinetis L MCU head to head with low-power 16-bit MCUs from Renesas, Texas Instruments, and Microchip. The chips ran 40 passes of the CoreMark benchmark then went to sleep before being awakened to repeat the exercise until they ran out of juice. Any guesses as to which MCU outlasted the rest? A hint: you can buy 10,000 of them for just 49 cents each.
But numerous MCU vendors have been using ARM-based microcontrollers to attract designers that traditionally use 8- and 16-bit microcontrollers. These MCUs offer the appeal of the ARM architecture, 32-bit flexibility, low prices, a robust ecosystem, and multiple suppliers. Some of these MCU vendors also focus heavily on reducing power consumption, using many of the same techniques that Freescale is employing in Kinetis L. Each end application has different performance requirements and different sleep patterns; those differences often determine the right MCU choice.
Kinetis L will open new markets for Freescale, but the company will face competition in those markets. For ARM and Cortex-M0+, this product is the first of many high-volume opportunities to further expand the reach of its architecture into the world of traditional 8- and 16-bit MCUs.