AD813AR-REEL Analog Devices, AD813AR-REEL Datasheet - Page 15

• Manufacturer Part Number: AD813AR-REEL
• Description: Single Supply/ Low Power Triple Video Amplifier
• Manufacturer: Analog Devices

REV. B
Figure 44. Circuit of Figure 38 Driving a 510 pF Load
Capacitor, V
R
Figure 43. Response to a Large Load Capacitor at
V
Figure 42. Response to a Small Load Capacitor at
V
S
S
S
=15 )
= 15 V
–3
–3
= 5 V
9
6
3
0
9
6
3
0
100
1
1
9 0
1 0
100
0 %
5 V
S
5V
C
= 15 V (R
L
= 510pF, R
10
10
FREQUENCY – MHz
FREQUENCY – MHz
S
= 15
L
R
= 1 k , R
S
= 30
R
S
= 50
C
L
= 150pF, R
100
100
R
F
S
= R
= 0
G
S
V
G = +2
R
R
C
V
G = +2
R
R
= 30
= 750 ,
S
1 00 n s
S
F
L
L
F
L
=
= 750
= 1k
= 10pF
=
= 750
= 1k
5V
15V
1000
1000
–15–
Overload Recovery
There are three important overload conditions to consider.
They are due to: input common-mode voltage overdrive, out-
put voltage overdrive, and input current overdrive. When the
amplifier is configured for low closed-loop gains, and the input
common-mode voltage range is exceeded, the recovery time will
be very fast, typically under 30 ns. When configured for a
higher gain, and overloaded at the output, the recovery time will
also be short. For example, in a gain of +10, with 6 dB of
input overdrive, the recovery time of the AD813 is about 25 ns
(see Figure 45).
In the case of high gains with very high levels of input overdrive,
a longer recovery time will occur. For example, if the input
common-mode voltage range is exceeded in the gain of +10, the
recovery time will be on the order of 100 ns. This is primarily
due to current overloading of the input stage.
As noted in the warning under Maximum Power Dissipation, a
high level of input overdrive in a high noninverting gain circuit
can result in a large current flow in the input stage. Though this
current is internally limited to about 40 mA, its effect on the
total power dissipation may be significant.
100
10
0%
90
Figure 45. 6 dB Overload Recovery, G = +10,
(R
L
= 500
2V
1V
, R
F
= 357
, V
S
=
5 V)
50ns
AD813