http://www.allaboutcircuits.com/vol_3/chpt_2/8.html
I have two questions about this section.
1. why is it that a common-base amplifier is being used as a introduction to amplifiers when it seems rarely used and hard to understand? Here are a few snippets from the section dedicated to common-base amps:
I have two questions about this section.
1. why is it that a common-base amplifier is being used as a introduction to amplifiers when it seems rarely used and hard to understand? Here are a few snippets from the section dedicated to common-base amps:
2. While the explanation of the 'fate' of electrons that enter the base was good and made sense, I didn't see an explanation of why more base current equates to more collector current. Why doesn't more base current mean less collector current? I understand transistors have a certain current gain. But why is this? Why wouldn't the collector current be exponentially related to the base current?"This configuration is more complex than the other two, and is less common due to its strange operating characteristics."
"Predicting voltage gain for the common-base amplifier configuration is quite difficult, and involves approximations of transistor behavior that are difficult to measure directly."
"The combination of low current gain (always less than 1) and somewhat unpredictable voltage gain conspire against the common-base design, relegating it to few practical applications."