Freescale's multicore ARM-based i.MX 7 processors maximise performance/power

June 23, 2015 // By Graham Prophet
Positioning them as the most power-efficient processors available in their class – with ARM Cortex-A7, GGz-speed cores – Freescale says its I.MX 7 devices provide maximised performance at one third the power of the i.MX 6 series; deep suspend mode enables “rich OS standby” power consumption of 250 µW.

This series of applications processors is based on the i.MX platform. The i.MX 7 series delivers core power efficiency of 15.7 DMIPS/mW, a new Low Power State Retention mode (LPSR) of 250 µW and is claimed as the first general purpose microprocessor family to incorporate both the ARM Cortex-A7 and the ARM Cortex-M4 cores. These technologies, together with Freescale's new companion PF3000 PMIC, are designed to enable secure and power efficient end-products for the wearable computing and Internet of Things (IoT) eras.

The first members of the series are the new i.MX 7Solo and i.MX 7Dual product families, which feature Cortex-A7 cores operating up to 1 GHz and a Cortex-M4 core operating up to 266 MHz. The Cortex-A7 and Cortex-M4 achieve processor core efficiency levels of 100 µW/MHz and 70 µW/MHz respectively. All of the cores can be individually power enabled to perform as needed. This performance-on-demand architecture allows the i.MX 7 series to meet the bursty, high-performance needs of running Linux, graphical user interfaces, wireless stacks or other high-bandwidth data transfers with one or both of the Cortex-A7 cores. When high levels of processing are not needed, the work can be transferred to the smaller, lower powered Cortex-M4, enabling the power gating of the Cortex-A7 core.

Freescale employs a 28nm ultra low leakage process technology and discrete power domain architecture; the LPSR mode consumes 250 µW, representing 48% power savings versus comparable devices, while supporting DDR self-refresh mode, GPIO wakeup, and memory state retention. Creating a system with power efficient processing and low power deep sleep modes enables a new tier of performance-on-demand, battery operated devices, Freescale says.

Target applications include wearables, secure point-of-sale equipment, smart home controls, industrial products and innovative IoT concepts. The i.MX 7 series also continues Freescale?s support for the e-Reader market via integration of an advanced, fourth-generation EPD controller.

“The i.MX 7 series scores industry leading dynamic and static power