Category: Transistor Amplifiers

Analysis of Common Base Amplifier (CB) using h-parameter: Figure 1 gives the basic circuit of a transistor (NPN type) used as a common base (CB) amplifier. In this case, Vs is the signal voltage, Vi is the actual voltage at the input terminals and V0 is the output voltage. Figure 2(a) gives the a.c. equivalent circuit obtained on having removed the dc source. On replacing the CB transistor with its small-signal two generator h-parameter model we get the equivalent circuit of figure 1(b). Here also we assume sinusoidal input. Hence…

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Transistor static characteristics curves are nonlinear. But for small signal operation, the point of operation moves about the quiescent operating point over a small range. Then the transistor parameters may be considered to be constant over this small range of operation. Derivation of h-Parameter model for transistor To drive the h-parameter model for a transistor, we consider the basic CE amplifier circuit of figure 1. The variable iB, iC, vB (=vBE) and vC(vCE) represent the instantaneous total values of currents and voltages. The input current iB and output voltage vC…

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