The differential difference amplifiers of sensor systems with input transistors of various physical nature
Nikolay Nikolayevich Prokopenko, Nikolay V. Butyrlagin, Anna V. Bugakova, Ilya V. Pakhomov · 2016
The article considers basic connection circuits of asymmetrical inputs and outputs (according to their features) of differential stages (ADS), realized on the transistors of various physical nature and operating principles (bipolar transistors, JFETs and CMOS FETs). It is shown that the nonidentity of input transistors and the instability of the output currents in one ADS can be compensated by differential connection of two unstable but identical ADSs. The application conditions of ADS of this class in differential difference (DDAs) and instrumentation amplifiers (IAs) of sensor systems and analog processors are set. The main feature of the suggested schematic solutions is the absence of classical reference current sources, setting the steady-state behavior of ADS. The static currents in the circuit are determined by geometrical dimensions of the used FETs. The results of DDA simulation on asymmetrical ADSs are given in conditions of thermal effects and neutron flux (Fn≤5·1013n/cm2).