OP249 Datasheet, PDF (15/17 Pages) Analog Devices – Dual, Precision JFET High Speed Operational Amplifier

OP249
OP249 SPICE MACRO-MODEL
Figures 53 and Table I show the node and net list for a SPICE
macromodel of the OP249 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 fre-
quency are also simulated by the model.
The model uses typical parameters for the OP249. The poles
and zeros in the model were determined from the actual open
and closed-loop gain and phase response of the OP249. In this
way the model presents an accurate ac representation of the
actual device. The model assumes an ambient temperature of
25°C.
2
IN–
I_OS
1
IN+
99
R1
C_IN 3
R2
I1
4
J1 J2
E_OS
V2
8
G1
7
D1
R5
C3
9
5
6
C2
R3
R4
50
D2
R6
C4
10
G2
V3
C5
G3
R7
12
R11 L1
G5
15
R9
R12
14
R10
G4 ^R8
13
C6
R13
16
G6
R14
L2
REV. C
99
G7 ^R15
C9
G9 R17 _C11
G11 R19 _C13
L3
G13 ²¹
R21
17
18
19
20
R22
G8 R16 C10
G10 R18 C12
G12 R20 C14
G14
22
L4
50
99
G15 R23
C15
23
D5
D6
G19
R25
D3 ₂₅
24
D4 ₂₆
V4
+–
29
V5
R27
L5 ₃₀
V_OUT
G16 R24
C16
R26
D7
27
28
R28
G20
G17 G18
D8
50
Figure 53. OP249 Macro-Model
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