DG884AM VISHAY [Vishay Siliconix], DG884AM Datasheet - Page 13

• Manufacturer Part Number: DG884AM
• Description: 8 x 4 Wideband Video Crosspoint Array
• Manufacturer: VISHAY [Vishay Siliconix]

A typical switching threshold versus V
These devices feature an address readback facility whereby
the last address written to the device may be read by the
system. This allows improved status monitoring and hand
shaking without additional external components.
When the I/O assigns the address output condition, the A
address pins can sink or source current for logic low and high,
respectively. Note that V
This point must be respected if V
threshold shifting.
Note: Even though these devices are designed to be latchup
resistant, V
operation or during power supply on/off sequencing.
Document Number: 70071
S-52433—Rev. G, 20-Dec-04
APPLICATIONS
L
In Bus
In Bus
Video
Video
must not exceed V+ by more than 0.3 V in
L
is the logic high output condition.
FIGURE 16. 16 X 8 Expandable Crosspoint Matrix Using DG884
L
is varied for input logic
L
Out Bus
Out Bus
Video
Video
is shown in Figure 15.
X
Layout
The PLCC package pinout is optimized so that large
crosspoint arrays can be easily implemented with a minimum
number of PCB layers (see Figure 16). Crosstalk is minimized
and off-isolation is optimized by having ground pins located
adjacent to each input and output signal pins. Optimum
off-isolation and low crosstalk performance can only be
achieved by the proper use of RF layout techniques: avoid
sockets, use ground planes, avoid ground loops, bypass the
power supplies with high frequency type capacitors (low ESR,
low ESL), use striplines to maintain transmission line
impedance matching.
Out Bus
Out Bus
Video
Video
Vishay Siliconix
In Bus
In Bus
Video
Video
DG884
www.vishay.com
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