Reversible electrically variable active parameter trimming apparatus utilizing floating gate as control

摘要

A continuously variable, reversible active circuit parameter trimming or adjustment method and apparatus are described. An active field effect transistor having a control gate to which a voltage is applied for the purpose of varying the conduction in the FET is achieved by supplying the control gate voltage from the stored voltage on a floating gate FET which has been charged to the desired variable level for controlling the conduction in the controlled FET at the desired operating point for parameter adjustment in an active circuit of which the FET may form a part. The floating gate FET structure can be electrically adjusted by charging or discharging the floating gate thereof which acts as a fixed memory to supply the appropriate control voltage to the controlled FET electrically connected thereto by a conductor connecting the control gate of the FET with the floating gate in the trimming or parameter adjustment floating gate FET element.