teknik otomasi industri smk jilid 1

248
Ui 1
R 1
No n Inv ert ing
Inp ut
+
I nve rt ing Inp ut
Ui2 GND
-
Ic1
6 K7
Uc1
T 1
T3
UE 1
R3 3K 3
IE 3
R2
Uc2
T2
6 K7
Dua l Input
ba lanced - out put
dife rent ial amp .
IB 3
T4
Ucc = 12 V
R4 3 K8
UE4
R5 9 K1
R6
IE 4
UB3
5K 5
T 5
Du al in put
umba lanced - outp ut
d ifer entia l a mp.
UB E 6
T6
R9
4 0 0
I1
UE
7
IE
7
UBE7 UBE 5 UE 6 T7 Ic8 IE 6
R7 15 K
Emitter
follower
UBE 8
T8
R8
Out put
sta ge
Gambar 2.196 Rangkaian Ekuivalen OP-AMP
Besarnya tegangan beda (Diferensial Voltage) UD:
UD = Ui1 – Ui2 ? UBET1 – UBET2 ? 0
(1.1)
UC1 = UCC - IC1 ? .R1
(1.2)
UEA = UC1-UBE5
(1.3)
Karena IB3 = 0 (kecil sekali)
Maka:
U E4 U EE
U U E4 E E IE4 I E4
R5 R5 R6 E
R UE 1 - 7
IE3
( 1 - 6 )
R6 (1.4)
UE3 = UB3 – UBE3
(1.5)
U U
UE3 U EE
E3 E
I
IE3 E3
3 - UEE
R 3
3
R 3
Karena IE3 = 2? IC1 dan IC1 = IC2
Maka :
R6 U CC U BE R6 R1 I C1 0,7
2 I C1 R5 R6 R R 3 5
(1.7)
R6 R3 R3 UE4 = UC1 – UBE5
(1.8)
UE 8
IE8
2 K
GND
- UEE