Cascode-type amplifier circuit e.g. for electronic equipment

摘要

An amplifier circuit including a first transistor, npn-type (T1) with an input signal (E) coupled in to its base circuit and whose controlled path is connected at one end to a first supply potential (VN). A second npn-type transistor (T2) has its base circuit connected to a bias potential, and its controlled path connected at one end to the other end of the first transistor's (T1) controlled path and delivering an output signal (A) at the other end. A third transistor, pnp-type (T3) has its base circuit connected to the other end of the controlled path of the second transistor (T2), and whose own controlled path is connected at one end to the second supply potential (VP). A fourth transistor, of pnp- type (T4) is connected by its base to the other end of the controlled path of the third transistor (T2), and its own control path connected at one end to the base of the third transistor (T).