Datasheet

THS3125
470 W
49.9 W
56.2
R
W
M
R
G
470 W
0.1 Fm
+
6.8 Fm
0.1 Fm
+
6.8 Fm
50- LoadW
50- SourceW
R
F
V
I
+V
S
-V
S
-15V
+15V
THS3125
470 W
49.9 W
49.9 W
470
R
W
G
0.1 Fm
+
6.8 Fm
0.1 Fm
+
6.8 Fm
50- LoadW
50- SourceW
R
F
V
I
+V
S
-V
S
-15V
+15V
THS3122
THS3125
www.ti.com SLOS382D –SEPTEMBER 2001– REVISED FEBRUARY 2011
APPLICATION INFORMATION
Current-feedback amplifiers are highly dependent on
Maximum Slew Rate for Repetitive Signals
the feedback resistor R
F
for maximum performance
The THS3125 and THS3122 are recommended for
and stability. Table 1 shows the optimal gain setting
high slew rate pulsed applications where the internal
resistors R
F
and R
G
at different gains to give
nodes of the amplifier have time to stabilize between
maximum bandwidth with minimal peaking in the
pulses. It is recommended to have at least 20-ns
frequency response. Higher bandwidths can be
delay between pulses.
achieved, at the expense of added peaking in the
frequency response, by using even lower values for
The THS3125 and THS3122 are not recommended
R
F
. Conversely, increasing R
F
decreases the
for applications with repetitive signals (sine, square,
bandwidth, but stability is improved.
sawtooth, or other) that exceed 900 V/µs. Using the
part in these applications results in excessive current
Table 1. Recommended Resistor Values for
draw from the power supply and possible device
Optimum Frequency Response
damage.
THS3125 and THS3122 R
F
and R
G
VALUES FOR MINIMAL
For applications with high slew rate, repetitive signals,
PEAKING WITH R
L
= 50 Ω, ±5-V to ±15-V POWER SUPPLY
the THS3091 and THS3095 (single versions), or
GAIN (V/V) R
G
(Ω) R
F
(Ω)
THS3092 and THS3096 (dual versions) are
1 — 560
recommended.
2 470 470
4 66.5 200
Wideband, Noninverting Operation
The THS3125 and THS3122 are unity gain stable
Wideband, Inverting Operation
130-MHz current-feedback operational amplifiers,
designed to operate from a ±5-V to ±15-V power
Figure 38 shows the THS3125 in a typical inverting
supply.
gain configuration where the input and output
impedances from Figure 37 are retained in an
Figure 37 shows the THS3125 in a noninverting gain
inverting circuit configuration.
of 2-V/V configuration used to generate the typical
characteristic curves. Most of the curves were
characterized using signal sources with 50-Ω source
impedance and with measurement equipment that
presents a 50-Ω load impedance.
Figure 38. Wideband, Inverting Gain
Configuration
Figure 37. Wideband, Noninverting Gain
Configuration
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Product Folder Link(s): THS3122 THS3125