Datasheet

ADA4522-1/ADA4522-2/ADA4522-4 Data Sheet
Rev. F | Page 26 of 33
A quick and easy way to stabilize the op amp for capacitive load
drive is by adding a series resistor, R
ISO
, between the amplifier
output terminal and the load capacitance, as shown in Figure 80.
R
ISO
isolates the amplifier output and feedback network from
the capacitive load. However, with this compensation scheme,
the output impedance as seen by the load increases, and this
reduces gain accuracy.
–V
SY
V
IN
+V
SY
V
OUT
C
L
ADA4522-1/
ADA4522-2/
ADA4522-4
R
ISO
13168-076
Figure 80. Stability Compensation with Isolating Resistor, R
ISO
Figure 81 shows the effect on overshoot with different values of
R
ISO
.
60
25
50
55
45
20
40
15
35
10
30
5
0
10 100 1k
OVERSHOOT (%)
LOAD CAPACITANCE (pF)
V
SY
= ±15V
R
L
= 10k
A
V
= 1
V
IN
= 100mV p-p
OS+ (R
ISO
= 0)
OS– (R
ISO
= 0)
OS+ (R
ISO
= 25)
OS– (R
ISO
= 25)
OS+ (R
ISO
= 50)
OS– (R
ISO
= 50)
13168-077
Figure 81. Small Signal Overshoot vs. Load Capacitance with Various Output
Isolating Resistors
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