Designing Dynamic Circuit Response (Analog Circuit Design Series: Volume 2) PDF

By deriving the complex-frequency expression for β from the BJT hybrid-π model, we can write the β-dependent impedance transformations at base and emitter nodes in a general form. When these impedances are represented graphically on a reactance chart, the effects of circuit element variations on circuit behavior, especially HF resonances, become evident. The frequency dependent β transform is also applicable to FETs and single-pole feedback amplifiers. They show the same impedance gyrations as the BJT, so the BJT results can be easily extended to them also.

Author

D. Feucht