4310 Week11 CB CC Amp Config
13
Transcript of 4310 Week11 CB CC Amp Config
-
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:
