Trimbar variabel kompressionsforstærker for høreapparater

摘要

An improved analog hearing aid is provided which incorporates a current source transconductance amplifier as an input stage. The gain defining bias current of the input stage transconductance amplifier is adjusted upon the application of battery power to the hearing aid to define a low input signal gain, and is then reduced by two gain regulators to define a compression threshold and compression ratio, and to provide a maximum output ceiling. Also provided is a method of trimming the low signal gain of the hearing aid at the time battery power is applied.