A

1
?????????
?????(inverting amplifier)
Virtual ground????
R2
?I
?O
????
R1
iI- 0
A
0V
iI0
????
???????
??finite open-loop gain A
?I
?O
G?I
R1
(????)
Input port
Output port
2
?T???????????(inverting amplifier with a
T-network)
i4
?x
i2
R2
R4
i3
R3
?I
?O
R1
iI- 0
A
0V
iI0
3
??
????????????????,????1MW,??100,??????????1MW????
???
100MW
R2
1MW
?I
?O
R1
98
?x
1MW
1MW
???
R2
R4
R3
1
10.2kW
1
1MW
?I
100
R1
?O
R3 1MW/9810.2kW
4
Current-to-Voltage Converter (CCVS)
Transresistance Amplifier
RF
iI(t)
iI
RF iI
?O
?O
Virtual ground
Voltage-to-Current Converter (VCCS)
iL
iI
iL
ZL
?I
ZL
R
?I
?O
iI
?O??????
5
Voltage Follower (Buffer) ???(???)
iI0
?I
?I
?O
?I
Ri
?O ?I
G1 ? Ri?? ? Ro?0
?? 1.??????2.??,??3.???????????4.?????????????
?
???????????????????????????????,???????,????????
180º,???????1,??????
6
Weighted Summer (?????)
Summing amplifier
R1
?1
i
i1
Rf
R2
?2
i2
?O
Rn
?n
in
7
?????(difference amplifier)
????????????,??????????2 0,????O1 ???1
0,????O2 ???O ?O1 ?O2
R2
R1
?1
?O
?2
R3
R4
R2
R2
R1
R1
?1
?1
?O2
?O1
?2
?2
R3
R3
R4
R4
8
?????????????CM ,??????d?,???????
??1 ?2 ?CM
?????0 CMRR?8
????R1R3, R2R4
?1
Ad?d
?2
????????,Ac0,Ad R2/R1
9
??????????
R2
??????
R1
i
?1
?d
?2
i
R1
R2
Virtual short circuit
R2
??????
R1
i1
?1
?d
?2
i2
R1
?????????1.???????2.?????3.????????
R2
?c
10
?????(instrumentation amplifier)
????
????IC??!