The Reference Ear Modeling Method for Internally Feedback Controlled Digital Hearing Aid Chip

A reference ear modeling method for the real-time feedback controlled digital hearing aid chip is proposed and implemented. In order to reduce the modeling complexity and enhance the programmability, new ear modeling method using the acoustic filter theory is adopted to the digital hearing aid. To achieve the fully internal gain fitting and verification system, the responses from the damaged ear and the reference ear model are compared and the new gain parameters are processed for the multi-channel DSP. The digital hearing aid chip with reference ear model is fabricated in 0.18 mum CMOS technology, has a core area of 3.1 mm times 1.2 mm and dissipates less than 120 muA.