An N-stage series transistor circuit

Summary form only given, as follows. A description is given of some of the characteristics of a circuit whereby a number of transistors may be connected in series so that the sum of their collector-to-emitter voltages appears across a common load. This circuit permits large output-voltage swings to be obtained without transformation and provides a convenient means for adding the power outputs of a number of units without requiring that their characteristics be closely matched. The analysis presented treats the circuit as a cascade of commonbase stages with specific values of external base resistance. The contributions of the individual stages to the total output is determined by the manner in which the base resistances are selected. Three cases are treated: one providing equal transistor voltages; another, equal power increase per stage; and the third, equal power output per transistor. Comparisons of the properties of the three cases are presented in tabular and graphical form. Consideration is given to a common-emitter input stage. Several practical circuits are described and experimental results shown to illustrate their performance.