Mixed-Signal SoC sets new standards for ultra-low-power, always-listening voice trigger

ON Semiconductor, driving energy efficiency innovations, has introduced BelaSigna R281, a new “always listening” voice trigger System-on-Chip (SoC) solution designed for popular consumer electronics devices such as smartphones, tablets and wearable devices. Using an audio pattern-matching algorithm developed by ON Semiconductor, BelaSigna R281 can detect a single, user-trained trigger phrase. This phrase can be any series of sounds, and is neither speech nor language dependent. Upon recognising this trigger phrase, BelaSigna R281 will assert a wake-up signal which, when connected to a host controller, alleviates the need for users to touch their device to wake it prior to use.

Based on ultra-low-power technology developed for the advanced hearing aid solutions that the company is already well-known for, BelaSigna R281 has virtually no impact on standby battery life. Unlike some standalone solutions which are only compatible with digital microphones, BelaSigna R281’s mixed-signal architecture works with both analogue and digital microphone signals. The device provides a configurable, regulated microphone supply to facilitate simple integration. Other key features of BelaSigna R281 include an I2C interface for configuration and control, a configurable GPIO wake-up signal, and an internal oscillator.

BelaSigna R281 is available in a 5 mm x 5 mm QFN32 package and will soon also be available in an ultra-miniature 2.42 mm x 2.74 mm WLCSP.  Both packages can be designed onto a single-sided PCB with 4 mil routing and a minimal amount of external components, providing one of the simplest solutions available for always-on, always-listening voice trigger.

“As the popularity of portable and wearable electronics devices has continued to grow, so has the demand for true hands-free operation” said: Michel De Mey, Senior Director, ON Semiconductor. “BelaSigna R281 supports voice triggered wake-up without placing unacceptable demands in terms of power, space, design-in complexity, and cost.”