User`s manual
VIDEO OVERVIEW
23
Input / Output sub-assemblies
The 64x64 digital video router is comprised of two plug-in sub-assemblies. One half of each of these
assemblies is a 64x33-crosspoint module. The 64x33 crosspoint module mates with a 33 channel output
driver module to complete the sub-assembly.
Because the basic crosspoint unit is a 64x33 module, the 96x96 frame is not suitable or cost-effective for
digital video.
The 128x128 frame has up to four plug-in sub-assemblies. Each of these is comprised of two 64x33
crosspoint modules and a 33 channel output driver. The output driver has thirty-three 2x1 switchers that
select between the output of the two 64x33 crosspoint modules. Thirty-two of these 2x1s are comprised
of ΒΌ of an 8x8 crosspoint IC configured as a 2x1 switch. Consequently, the 128x128 digital router signal
path only passes through two cascaded crosspoints.
The outputs of the 2x1 switches connect to a re-clocking circuit. The re-clocking circuit automatically
switches to the correct data rate, which supports up to four data rates. The standard digital Yosemite
64x64 and 128x128 systems are shipped with re-clocking set to 143mbps, 177mbps, 270mbps, and
360mpbs. If another data rate is desired or if the re-clocker needs to be bypassed, contact Sierra video
for additional information.