NXP i.MX RT106A Arm Cortex-M7 MCU for Alexa

Posted by Charbax – October 28, 2019

Turnkey, low cost i.MX RT solution speeds time to market. Cloud-based voice assistants, led by Amazon’s Alexa, have become common in many homes, embedded in smart speakers like Amazon’s Echo products. Soon, the newly emerging trend to build voice assistants directly into smart devices such as light switches, ceiling fans, appliances, smoke detectors, and thermostats, will make voice control ubiquitous throughout the home. Voice assistants conveniently and unobtrusively located throughout the home enable a family’s entire network of connected smart devices to be controlled by voice commands from any room. For example, “Alexa, turn off all the lights,” or even more powerful routines can be created such as, “Alexa, good morning,” which can turn on music, start the coffee pot, adjust the thermostat settings, and more.

Today, a few smart home device and appliance makers are introducing versions of their products with built-in voice assistants. Until now, the technology required to embed cloud voice assistants has required a powerful multicore microprocessor unit (MPU), similar to the application processor in smart phones, with large Flash and SDRAM memories, and complex power management. Such implementations have not been a fit for cost sensitive consumer devices, which has impeded the proliferation of smart home devices with built-in voice.

At Embedded World this week, NXP Semiconductors announced the first MCU based implementation of an Alexa client, based on a new member of NXP’s popular i.MX RT crossover processor family of devices. This new solution enables device makers to build Alexa into products using a low cost, low power microcontroller unit (MCU), a device that is typically already required in any connected smart home product, meaning that OEMs can now add voice to their products at very low incremental cost (not much more than the cost of the microphones). Running on Amazon FreeRTOS, NXP’s new MCU-based AVS solution leverages the power of AWS IoT Core to minimize the processing resources needed to build Alexa into a product. Compared to previous implementations running Linux with large memory footprints, requiring more than 50 MB RAM and several Giga-Bytes of Flash, NXP’s MCU solution needs less than 1 MB of on-chip RAM and fewer than 16 MB of Flash, significantly reducing cost and size.

The i.MX RT106A (“ten-sixty-a”), has a 600 MHz Arm™ Cortex-M7™ processor, 1 MB of on chip SRAM, an LCD display, camera interface, advanced security and flexible communication, combined with a complete turnkey AVS software solution and a production ready hardware design, to enable OEMs to quickly and easily add Alexa to their product designs.

With this solution, device makers realize further benefits of shorter time to market, lower development and lifetime costs. It brings together the Alexa Voice Service, AWS IoT Core, and Amazon FreeRTOS to provide complete and best-in-class security, deployment, and device monitoring.

NXP’s i.MX RT MCU-based AVS solution is available as a complete kit for evaluation, development and prototyping. The hardware consists of two small, 30 mm x 40 mm (1.2” x 1.6”) boards. The MCU system on module (SoM) carries the i.MX RT106A processor, 32 MB of HyperFlash memory, a Wi-Fi/Bluetooth module and an optional NXP A71CH secure element. The audio board has three MEMS microphones and connects to a speaker driven by NXP’s TFA9894D smart audio amplifier. The hardware ships with software that includes everything necessary for a developer to, out-of-the-box, connect to the Alexa Voice Service and immediately start prototyping. This one-stop-shop software package includes far-field voice processing (echo cancellation, noise suppression, beam forming, barge-in), an Alexa wake word inference engine, an AVS client application, API and all necessary drivers.

Samples of the i.MX RT106A processor and the SLN-ALEXA-IOT solution kit are available to qualified early access customers now.