AD9300TE/883B AD [Analog Devices], AD9300TE/883B Datasheet - Page 7

• Manufacturer Part Number: AD9300TE/883B
• Description: 4 x 1 Wideband Video Multiplexer
• Manufacturer: AD [Analog Devices]

CROSSPOINT CIRCUIT APPLICATIONS
Four AD9300 multiplexers can be used to implement an 8
crosspoint, as shown in Figure 11. The circuit is modular in
concept, with each pair of multiplexers (#1 and #2; #3 and #4)
forming an 8
are connected as shown, the result is an 8 2 crosspoint circuit.
REV. A
Figure 11. 8 x 2 Signal Crosspoint Using Four AD9300
Multiplexers
Figure 8. Pulse Response
1 crosspoint. When the inputs to all four units
Figure 9. T-Step Response
2
–7–
The truth table describes the relationships among the digital in-
puts (D
input is selected at the outputs (OUT
ber of crosspoint modules that can be connected in parallel is
limited by the drive capabilities of the input signal sources. High
input impedance (3 M ) and low input capacitance (2 pF) of
the AD9300 help minimize this limitation.
D
or
D
0
0
0
0
1
1
1
1
Adding to the number of inputs applied to each crosspoint
module is simply a matter of adding AD9300 multiplexers in
parallel to the module. Eight devices connected in parallel result
in a 32 1 crosspoint, which can be used with input signals hav-
ing 30 MHz bandwidth and 1 V peak-to-peak amplitude. Even
more AD9300 units can be added if input signal amplitude
and/or bandwidth are reduced; if they are not, distortion of the
output signals can result.
When an AD9300 is enabled, its low output impedance causes
the “off” isolation of disabled parallel devices to be greater than
the crosstalk rejection of a single unit.
2
5
0
–D
5
) and the analog inputs (S1-S8) and which signal
8
0
0
1
1
0
0
1
1
D
or
D
1
4
2 Crosspoint Truth Table
Figure 10. Enable to Channel
“Off” Response
1
D
or
D
0
1
0
1
0
1
0
1
and OUT
0
3
AD9300
2
). The num-
OUT
or
OUT
S
S
S
S
S
S
S
S
1
2
3
4
5
6
7
8
1
2