lec22_imp_view

lec22_imp_view - Common Emitter (with degeneration): R E R...

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± Small Signal Models of the Bipolar Transistor 6.301 — Spring 2002 Massachusetts Institute of Technology Michael Perrott (Courtesy of Michael Perrott. Used with permission.) General Thevenin Resistance View R E R B R C R th c I C R th e R th b R C R th c R th b R E R th e R B g m v π v π r π r o I c V th ,V th = V th kT q 25 mV at room temp ~ ~ g m = β o r π = , β o ~ 100 to 200 ~ g m V A r o = I c ,V A ~ 100 to 200 V ~ Thevenin resistance at collector: (1 + g m r o ) R E ( r π + R B / (1 + g m r o )) R th c = + r o R E + r π + R B R th c (1 + g m ( r π || R E )) r o for R B ± r π ,R E Thevenin resistance at base: r o + R C / ( β o +1) R th b = r π +( β o +1) R E r o + R C + R E R th b r π +( β o +1) R E for R C ± r o ,R E ± r o Thevenin resistance at emitter: r π + R B r o R th e = 1+ β o || 1+ R C / ( r π + R B ) 1 1 R B R th e + R B for r o ² + g m 1+ β o 1+ R C / ( r π + R B ) g m 1+ β o
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± ² ² ³ ³ Amplifier Configurations
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Unformatted text preview: Common Emitter (with degeneration): R E R B R C V in R th b R B v in G m v 1 v 1 R th c R C v out V out 1 R E / ( o r o ) g m G m = g m for R E r o , g m r o 1 1 + g m R E (1 + 1 / o + 1 / ( g m r o )) 1 + g m R E Emitter Follower: V in R E R B R C R th b R B v in A v v 1 v 1 R E R th e v out V out 1 A v = 1 1 + (1 + R C ) / ( r + o r o ) Common Base: V in R th e R E v in G m v 1 v 1 R th c R C v out V out R E R B R C r 1 G m = g m + g m for R B r , r o 1 /g m R B + r r o...
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This note was uploaded on 07/20/2009 for the course CSAIL 6.012 taught by Professor Prof.cliftonfonstadjr. during the Fall '03 term at MIT.

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lec22_imp_view - Common Emitter (with degeneration): R E R...

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