lmh6522sqe National Semiconductor Corporation, lmh6522sqe Datasheet - Page 20

• Manufacturer Part Number: lmh6522sqe
• Description: High Performance Quad Dvga
• Manufacturer: National Semiconductor Corporation

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OIP3 and Gain Measured at Amplifier Output, Filter Back
Printed circuit board (PCB) design is critical to high frequency
performance. In order to ensure output stability the load
matching resistors should be placed as close to the amplifier
CASCADE OPERATION
With four amplifiers in one package the LMH6522 is ideally
configured for cascaded operation. By using two amplifiers in
series additional gain range can be achieved. The schematic
in
LMH6522. The resultant frequency response is shown below
in
configuration it is important to keep the signal level within
reasonable limits at all nodes of the signal path. With over
40dB of total gain it is possible to amplify signals to clipping
levels if the gain is not set correctly.
Figure
Figure 8
9. When using the LMH6522 amplifiers in a cascade
shows one way to connect two stages of the
Terminated
FIGURE 8. Schematic for Cascaded Amplifiers
FIGURE 7. Output Configuration
20
output pins as possible. This allows the matching resistors to
mask the board parasitics from the amplifier output circuit. An
example of this is shown in figure
bandpass filter with no DC path the 0.01µF coupling capaci-
tors can be eliminated. The LMH6522EVAL evaluation board
is available to serve a guide for system board layout.
FIGURE 9. Frequency Response of Cascaded Amplifiers
-10
-20
50
40
30
20
10
0
1
FREQUENCY (MHz)
10
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Figure
100
30127383
7. If the FIilter is a
1000
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