A Fully Integrated Digital Hearing-Aid Chip with Human-Factors Considerations

A digital hearing-aid chip integrates a pre-fitting verification algorithm to obtain gain fitting in two steps: coarse and fine. The internal ear canal modeling filter circuit enables the coarse fitting based on the shape of the external ear. Fine fitting verification is performed with external inputs. The 3.74mm
²
chip draws less than 120 μA from a single 0.9V supply in a 0.18 μm CMOS technology.