Using onsemi DSP, Wirelessly Connecting Hearing Aids and Cochlear Implants


onsemi has taken a step forward in future hearing aid development by launching the Ezairo® 7150 SL, a power management and wireless-capable audio processor.

The Ezairo® 7150 SL wirelessly connects hearing aids and cochlear implants using onsemi's proprietary digital signal processing (DSP) technology, which has already been widely adopted by the industry. The compact hybrid module is based on the powerful Ezairo 7100 open programmable 24-bit mixed-signal DSP platform.

This System-in-Package (SiP) solution provides wireless multi-protocol operation and is optimized for 2.4 gigahertz (GHz) band applications, including Bluetooth Low Energy (BLE). The Ezairo® 7150 SL integrates the EA2M, a low-power 2Mb serial CMOS EEPROM used for hearing aid firmware storage, along with parameters.

onsemi provides a reference design for behind-the-ear (BTE) hearing aids to simplify and accelerate the development process of products based on the Ezairo® 7150 SL. The reference design includes software, hardware, and firmware that enable the latest wireless technologies. With the BLE Control (CoBLE) function, hearing aid users can adjust an array of parameters from their smartphones.

Hearing aid users can adjust the volume, change operating program modes, check battery status at any time, and receive mobile phone alerts (such as incoming calls or text messages). In the event of a lost hearing aid, the critical "Find My" feature enables quick recovery.


"Find My" Feature Also Available in Case of Loss

The patented stereo audio streaming protocol allows music to stream from any external audio source—smartphones, tablets, televisions, and more—through a remote dongle. The wireless connection range extends to a maximum of 10 meters in favorable ambient conditions.

The HPM10 is a power management IC (PMIC) that provides a high-performance solution for rechargeable batteries in hearing aids and hearing implant devices. The PMIC generates the voltage required for hearing aids and manages charging algorithms that optimize battery autonomy and charging cycle frequency. Rechargeable secondary battery types include silver-zinc (AgZn) and lithium-ion (Li-ion). The HPM10 also detects but does not charge air-zinc (Zn-Air) and nickel-metal hydride (Ni-Mh) batteries.

The HPM10's high-efficiency power regulator minimizes power loss flowing from the battery to the hearing aid during operation. The built-in Charger Communication Interface (CCIF) in the HPM10 transmits data to the hearing aid charger during charging.

Battery parameters such as voltage rating, current rating, temperature, and various types of battery faults are also detected and managed. Other charging parameters and representative battery sizes and types can all be stored in the HPM10's OTP (One Time Programmable) memory.

Michael De Mey, Senior Director at onsemi, stated: "Our new solution provides innovative capabilities to hearing aid design and end-user experience. The Ezairo® 7150 SL enables significantly enhanced user control directly from any BLE-enabled smartphone. Through hearing aids equipped with this solution, users can listen to audio from all audio sources, such as televisions and HiFi audio systems."