Even the simple common emitter circuit can result in some pretty complicated expression for the frequency response. The inclusion of a single element, the base-collector capacitance, introduces much complexity. This circuit is analyzed in detail by most of the textbooks, including Gray & Meyer's. None of them makes use the EET. We give a derivation using Middlebrook's EET to see if the analysis is simplified.
This is a little bit less work than the more direct method,
The two methods produce the same expression, so using EET does not give more insight.
The base-collector capacitor results in an additional pole and a right-hand side zero and shifts the dominant pole. The dominant pole can be approximated from the input capacitance and the Miller capacitance.
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