AMI Semiconductor's BelaSigna 200 DSP-based audio system was selected by Phonak Communications for the SmartLink SX, a communication device that provides hearing aid users with clear speech input in adverse listening situations. It also enables them to communicate easily through mobile phones and other Bluetooth-compatible devices.
Even with the best hearing instruments, most hearing-impaired people notice that certain situations present more hearing difficulties. Using a wireless communication system (FM system) makes communication easier. Such a system consists of a handheld microphone (SmartLink SX) that picks up the sound as close as possible to the source, along with a miniaturised receiver (MicroLink) that is clicked upon the hearing instrument.
Sound-processing algorithms developed by Phonak, including a digital beamformer, work with the AMIS BelaSigna 200 chip to remove noise and deliver clear speech to hearing aid users. Through integral microphones, audio inputs, and a Bluetooth link, the SmartLink receives and processes audio signals and transmits them to the user's hearing aid using Phonak's MicroLink technology.
The single-chip BelaSigna 200 interfaces seamlessly with wireless devices and consumes only a few milliamps of current at 1.8 V. It contains a DSP core, stereo CODEC, memory, power management, and a hardware-based WOLA filterbank coprocessor, which reduces power consumption and chip size while providing low group delay and adjustable parameters for easy integration into a range of designs.