C.5. Effect of Finite Slope of the Transistor Output Characteristic
As discussed in Unit C.2, the signal model contains an output resistance, which reflects the fact that the output characteristic of the transistor has a finite slope. This is characterized with the SPICE parameter VAF. It was noted that the effect of the finite slope is to place a resistance effectively across the output of the amplifier. It is calculated from ro = VAF/IC, (C.13).
With increasing bias current, ro may not be negligible compared to RC. In the project on the gain of the amplifier, we will read the experimental data into a Mathcad file and adjust VAF to make the SPICE calculation and measured data match. The gain expression that includes transistor output resistance ...
Get Analog Electronics with LabVIEW® now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
