A Real-Time Feedback Controlled Hearing Aid Chip with Reference Ear Model

A real-time hearing aid chip with the reference ear model (REM) and the comparison processor (COMP) is proposed and implemented. Through the COMP the response differences between the reference ear model and the impaired ear of the patient are achieved and processed to compensate the hearing loss of the patient. By adopting this architecture, the fully internal gain fitting and verification of the hearing aid with only single initial hearing loss test is implemented. To reduce the power dissipation and achieve the high flexibility, the preamplifier which has programmable multi threshold voltages is introduced. The feedback controlled hearing aid chip is implemented in 0.18 mum CMOS technology, consumes less than 110 muW and has a die size of 3.7 mm².