D.C. Amplifier with improved characteristics with respect to temperature

摘要

A D.C. amplifier for low-level currents includes an input stage having first and second cascode mounted transistors and a bis circuit adapted to maintain the base and collector potentials of the first transistor very close to each other over a predetermined temperature range. The amplifier is particularly suited for use in a flame detection device and, in addition, may include a protection circuit for the base-emitter junction of the first transistor.