4. Using the GX9533 to Expand Larger Matrices
The GX9533 pin-out and architecture provides a number of advantages over other
crosspoint switches in the area of switching matrix board layout.
GX9533
GX9533
GX9533
GX9533
OUTPUTS 0-7
OUTPUTS 8-15
Figure 4-1: Crosspoint Matrix Expansion - 16x16 Crosspoint Matrix
4.1 Bus Through™ Pin Connections
To easily facilitate a switching matrix design where inputs can be bussed across a matrix
of crosspoint devices, Gennum's crosspoint device has "NC" pins opposite the input pins
as shown by the dotted lines in the pin-out diagram above. This design allows bussing of
inputs without having to use "vias" to get below the top layer of the printed circuit board.
4.2 Expansion Port Input
The expansion inputs provide the following benefits:
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•
•
•
by not having to run traces from the outputs of the crosspoint switch to a common
output bus, crosstalk between output channels can be greatly reduced.
fewer circuit board layers are required because the outputs of each device simply
line up
there are no transmission line effects caused by connecting High-Z outputs to an
output bus
because the output signal is being routed from the top of the switching matrix to the
bottom through the devices, inputs can be simply bussed across the board without
having to worry about input/output crosstalk.
GX9533 Serial Digital 8x9 Crosspoint
Data Sheet
13 of 15
8494 - 4
November 2009
Proprietary & Confidential
GENNUM [ GENNUM CORPORATION ]
