Current gain in Class AB push-pull amplifiers is primarily determined by the relationship between emitter current and base current, expressed as the ratio i_e/i_b. This ratio can be approximated as h_fe + 1, where h_fe represents the transistor's beta. In the case of Darlington pairs, the "+1" can often be disregarded, simplifying calculations. However, for single transistors operating at high currents, this additional factor may become significant, potentially lowering the gain to around 10. Understanding these nuances is crucial for accurate amplifier design and performance assessment.
