Turn-off gain in p-n-p-n triodes☆

Abstract It has long been recognized that large turn-on gain can be achieved in p - n - p - n triodes when driven through the base. On the other hand, it has been recognized only recently that these devices can also be turned off through the base with large gain. In this paper we shall discuss in detail the mechanism of base-current turn off and show how large turn-off gain can be achieved. Several structures in which large turn-off gain can be attained will be described. Electrical characteristics of experimental models which show gains approaching 40 at collector currents of about 100 mA will be presented.