OP497
OP497 SPICE MACRO-MODEL
Figure 12 and Table I show the node and net list for a SPICE
macro-model of the OP497. The model is a simplified version of
the actual device and simulates important dc parameters such as
V
OS
, I
OS
, I
B
, A
VO
, CMR, V
O
, and I
SY
. AC parameters such as slew
rate, gain and phase response, and CMR change with frequency
are also simulated by the model.
The model uses typical parameters for the OP497. The poles and
zeros in the model were determined from the actual open and
closed-loop gain and phase response of the OP497. In this way,
the model presents an accurate ac representation of the actual
device. The model assumes an ambient temperature of 25°C.
99
V1
R3
C2
5
2
–IN
R
IN2
8
Q1
R1
C
IN
R
IN1
1
7
I
OS
R2
+IN
–+
E
OS
9
D1
D2
10
R5
Q2
11
98
R6
E
REF
14
I
1
50
CCM
RCM1
15
ECM
RCM2
16
17
ENZ
RNZ2
CNZ
RNZ1
18
G2
19
R10
20
R15
C5
V2
D4
G1
R7
C3
6
R4
12
13
D3
C5
G2
98
99
R16
I
SY
21
20
D7
D8
–+
22
–+
V4
D5 23
24
V3
G6
R18
L1
V
O
27
R19
R17
D9
25
G4
26
G5
D6
D10
G7
50
Figure 12. OP497 Macro Model
–10–
REV. D
AD [ ANALOG DEVICES ]
