Datasheet

+
-
75 Ω
75 Ω
1.24 kΩ1.24 kΩ
5 V
DAC Output
Input Range
V
O
Range
= 0 V to 1.25V
470 µF
= 0 V to 1.25V
5 V
47 µF
4.64 kΩ
2.26 kΩ
Output Range
= 2 V to 4.5 V
= 1 V to 2.25V
+
−
75 Ω
75 Ω
2.49 kΩ1.24 kΩ
5 V
DAC Output
Input = 2.5 V
V
O
Range
= 0 V to 2V
470 µF
= 0 V to 2V 5 V
10 kΩ
10 kΩ
Output Range
= 0.5 V to 4.5V
68 µF
10 µF
APPLICATION CIRCUITS
Active Filtering With the SN1050x
+
-
75 Ω
75 Ω
1.24 kΩ1.24 kΩ
5 V
DAC Output
Input Range
V
O
Range
= 0 V to 2V
470 µF
= 0 V to 2V
5 V
47 µF
3.01 kΩ
3.01 kΩ
Output Range
= 1.5 V to 3.5V
= 0.5 V to 4.5V
68 µF
_
+
49.9 Ω
50 Ω Source
1.3 kΩ
4.7 pF
5 V
−5 V
33 pF
V
O
1.3 kΩ
52.3 Ω
V
I
Driving Capacitive Loads
+
-
75 Ω
75 Ω
1.24 kΩ1.24 kΩ
5 V
DAC Output
Input Range
V
O
Range
= 0 V to 2V
470 µF
= 0 V to 2V
5 V
47 µF
3.01 kΩ
3.01 kΩ
Output Range
= 1.5 V to 3.5V
= 0.5 V to 4.5V
2.5 V
SN10501
SN10502
SN10503
www.ti.com .................................................................................................................................................. SLOS408B – MARCH 2003 – REVISED JANUARY 2009
Figure 41. AC-Coupled Input and Output
Figure 44. Inverting AC-Coupled Wide Output
Single-Supply Video Amplifier
Swing Single-Supply Video Amplifier
To further increase dynamic range at the output, the
output dc bias should be centered around 2.5 V for
the 5-V system shown. However, a wide output range
requires a wide input range, and should be centered
around 2.5 V. The best ways to accomplish this are
High-frequency active filtering with the SN1050x is
to ac-couple the gain resistor or bias it at 2.5 V with a
achievable due to the amplifier's high slew rate, wide
reference supply as shown in Figure 42 and
bandwidth, and voltage feedback architecture.
Figure 43 .
Several options are available for high-pass, low-pass,
bandpass, and bandstop filters of varying orders. A
simple two-pole, low-pass filter is presented in
Figure 45 as an example, with two poles at 25 MHz.
Figure 42. AC-Coupled Wide Output Swing
Single-Supply Video Amplifier
Figure 45. A Two-Pole Active Filter With Two
Poles Between 90 MHz and 100 MHz
A demanding, yet very common application for an op
amp is capacitive loading. Often, this load is the input
of an A/D converter, including additional external
capacitance, sometimes recommended to improve
A/D linearity. A high-speed, high open-loop gain
Figure 43. AC-Coupled Wide Output Swing
amplifier like the SN1050x can be very susceptible to
Single-Supply Video Amplifier Using Voltage
decreased stability and closed-loop response peaking
Reference
when a capacitive load is placed directly on the
output pin. When the amplifier's open-loop output
resistance is considered, the capacitance introduces
Another beneficial configuration is to use the amplifier
an additional pole in the signal path that can
in an inverting configuration as shown in Figure 44 .
decrease the phase margin. When the primary
considerations are frequency-response flatness,
pulse response fidelity, or distortion, the simplest and
most effective solution is to isolate the capacitive load
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