4310 week11 cb cc amp config

Download 4310 Week11 CB CC Amp Config

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  • 18

    CB Amplifier

    Ai=

  • 0.5mA

    1K100K

    50

    50

    +

    ?

    ?

    .

    250.5

    5050 50 .

    19.8 0.5 .

    1 100 150 .

    ||

  • 20

    CC Amplifier

  • +9V +9V

    100K

    10K

    1K 1K

    20?

    ?

    ???

    9 0.7

    1 1001.

    1 1.44 .

    1.44 0.7 .

    100 ||{ 1 1 ||1 ,.

    .

    ACDC

    .100

    10 100 1 1 1

    100 10 1 17.4 1 1||

    || ||

    .

    KVL

  • 25

    Table 5.6

    CE CE+RE

    CB CC

  • 26

    Transistor as a switch: Cut-off and Saturation

    If vI < 0.5 V EBJ is offand CBJ is off

    Thus the transistor is in cut-off mode

    iB = 0 , iC = 0 , iE = 0

    In Active mode VBE 0.7 V vI > VBE

    iB = (vI VBE)/RB =(vI 0.7)/RB , iC= iB

    To verify that the transistor is in active mode:

    vC = VCC iC RC if vCB>0 active

  • 27

    When VC = VB Edge of Saturation

    IC=(VCC-VB)/RC=(VCC-0.7)/RC= IB

    VI = RBIB + VBE

  • 28

    If VCB0 Transistor enters Saturation 0.4V-0.6V

    0.3V>VCE>0.1V

    VCE=VBE+VCBVCEsat= 0.2V

    In Deep Saturation

  • 29

    In Deep Saturation:

    VCE = VCEsat = 0.2V

    IC=ICsat=(VCC-VCEsat)/RC

    ICsat= forced IB

    The transistor in Deep Saturation is modeled as: