Sensor hubs that offload tasks from power-hungry application processors and let mobile devices like smartphones and tablets run longer on a single battery charge are reaping gargantuan gains thanks to the global microelectromechanical systems (MEMS) market, with shipment growth this year alone in triple-digit territory, according to new analysis from IHS Technology.
Worldwide shipments of sensor hubs in 2014 will reach a projected 658.4 million units, up 154% from 259.6 million units last year. The market has been on a tear since 2011, when shipments first started from a low initial base. The 2012 growth rate, for instance, exceeded 2,000 percent.
From then until 2017, the market is pegged to increase 1,300% to shipments of 1.3 billion units.
“A sensor hub is a low-power processor that can be used to perform calculations on data from sensors, the hub thereby saving power on a device by off-loading such tasks from the power-intensive application processor,” said Marwan Boustany, senior analyst for MEMS & sensors at IHS. “The use of sensor hubs is increasingly crucial because of the push for ‘always on’ sensors used for activity monitoring, voice-command operation and contextual awareness.”
Most of sensor processing today is performed by software running on an application processor, but this approach is too power hungry when sensor processing must continuously run in the background. With rising use by handsets and tablets of sensors--not just motion sensors but also microphones and light sensors--the need for a low-power solution becomes crucial.
By centralizing sensor processing in a more efficient way through sensor hubs, power usage and battery life are optimized, Boustany added.
These findings are contained in the report, “Motion Sensors Report - Handsets and Tablets – 2014,” from the Semiconductor & Components service of IHS.
Sensor Formats Vie to Deliver Maximum Benefits
The centralized processing in a sensor hub is typically achieved via three different approaches, each with its own advantages along with specific tradeoffs in cost or performance.
One approach employs an external hub, typically a dedicated microcontroller (MCU), as offered by the likes of chip makers such as Atmel, STMicroelectronics, Texas Instruments and NXP Semiconductor. Recent smartphones that use this approach include the Apple iPhone 5s, Samsung Galaxy S5 and the Motorola Moto X.
A second method utilizes a low-power sensor hub as part of an application processor, offered by Qualcomm, Intel and Nvidia through a low-power core--and in the future to be provided as well by Samsung’s Exynos, MediaTek, and HiSilicon. Such an integrated approach has advantages compared to the discrete MCU format, reducing additional chip-design efforts and entailing no additional components, but it also cannot compare for now to the lower power delivered by MCUs.