Find voltage gain of three-stage amplifier

Thread Starter

Joel Ong

Joined Nov 23, 2019
8
How can the voltage gain of each stage be found? (The differential input stage, the common emitter gain stage, the emitter follower output stage) The R18 is changed to 20kohms and C9 is changed to 500pF. Screenshot (626).png
 

ronsimpson

Joined Oct 7, 2019
680
Q7, Q8 has current gain but no voltage gain. Gain=1 (output stage)

The closed loop gain is set by R17 and R18. (depends on frequency because C8 and C9 effects the gain) The gain is 30x set by resistors and that is spread out over Q3,4 and Q5,6.
Open loop gain is found by removing R18.
 
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