AD8010AR-REEL7 Просмотр технического описания (PDF) - Analog Devices
Номер в каталоге
Компоненты Описание
производитель
AD8010AR-REEL7 Datasheet PDF : 12 Pages
| |||
AD8010
Closed-Loop Gain and Bandwidth
The AD8010 is a current feedback amplifier optimized for use
in high performance video and data acquisition applications.
Since it uses a current feedback architecture, its closed-loop
–3 dB bandwidth is dependent on the magnitude of the feedback
resistor. The desired closed-loop bandwidth and gain are obtained
by varying the feedback resistor (RF) to set the bandwidth, and
varying the gain resistor (RG) to set the desired gain. The char-
acteristic curves and specifications for this data sheet reflect the
performance of the AD8010 using the values of RF noted at the
top of the specifications table. If a greater –3 dB bandwidth
and/or slew rate is required (at the expense of video performance),
Table I provides the recommended resistor values. Figure 32
shows the test circuit and conditions used to produce Table I.
Effect of Feedback Resistor Tolerance on Gain Flatness
Because of the relationship between the 3 dB bandwidth and the
feedback resistor, the fine scale gain flatness will, to some extent,
vary with feedback resistor tolerance. It is therefore recommended
that resistors with a 1% tolerance be used if it is desired to main-
tain flatness over a wide range of production lots. In addition,
resistors of different construction have different associated para-
sitic capacitance and inductance. Metal-film resistors were used
for the bulk of the characterization for this data sheet. It is pos-
sible that values other than those indicated will be optimal for
other resistor types.
Quality of Coaxial Cable
Optimum flatness when driving a coax cable is possible only
when the driven cable is terminated at each end with a resistor
matching its characteristic impedance. If the coax was ideal,
then the resulting flatness would not be affected by the length of
the cable. While outstanding results can be achieved using inex-
pensive cables, it should be noted that some variation in flatness
due to varying cable lengths may be experienced.
Table I. –3 dB Bandwidth and Slew Rate vs. Closed-Loop
Gain and Resistor Values
Package: N-8
Closed-Loop
Gain
+1
+2
+5
+10
RF (⍀)
453
374
348
562
RG (⍀)
∞
374
86.6
61.9
–3 dB BW
(MHz)
285
255
200
120
Slew Rate
(V/s)
900
900
800
550
Package: R-16
Closed-Loop
Gain
+1
+2
+5
+10
RF (⍀)
412
392
392
604
RG (⍀)
∞
392
97.6
66.5
–3 dB BW
(MHz)
245
220
160
95
Slew Rate
(V/s)
900
900
800
550
Package: SO-8
Closed-Loop
Gain
RF (⍀)
+1
392
+2
374
+5
348
+10
499
RG (⍀)
∞
374
86.6
54.9
1. VO = 0.2 V p-p for –3 dB Bandwidth.
2. VO = 2 V p-p for Slew Rate.
3. Bypassing per Figure 29.
–3 dB BW
(MHz)
345
305
220
135
Slew Rate
(V/s)
950
1000
1000
650
150⍀
VIN
50⍀
VOUT
RF
18.75⍀
RG
Figure 32. Test Circuit for Table I
REV. B
–11–
Share Link: 