Filter for microphone, includes pair of transistors of which one is connected to output of microphone through capacitor and another to constant current source at current and control electrode ends

摘要

A pair of transistors (T3,T4) of filter (FT1) are connected in a mirror circuit. The output of a microphone is connected to a current electrode of transistor (T3) through capacitor (C1). A constant current source (IS) is connected to a current electrode and control electrode of transistor (T4). An Independent claim is also included for microphone device.