SA8702
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DESCRIPTION
The SA8702 (BMTSAC) is a Block Mode
Time Slot Allocation Circuit. The device is
used to generate 8 consecutive timeslots
in one of 4 blocks in a 32 time-slot PCM
system. Each timeslot pulse is 8 BLCK
cycles long. BCLK is the 2,048 station
clock provided by the system. An active
MRST will disable all outputs until a valid
XSYNC input is recognised. The output
TSX is delayed by half a cycle and indicates
that one of 8 timeslots is currently active.
There are 4 possible modes of operation,
selectable by means of the BL0 and BL1
pins (See Table 1).
APPLICATIONS
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SA8702
BLOCK MODE TIME SLOT ALLOCATION CIRCUIT
PCM Switching Systems
PCM Transmission Systems
Subscriber Multiplex Equipment
PBX Systems
PIN CONNECTIONS
All inputs and outputs are C-MOS
compatible. All outputs are push-pull with
the exception of TSX which is open drain.
The inputs MRST and BCLK are Schmitt
Trigger. Inputs BL0 and BL1 have pull-ups.
(See figure 1).
Figure 1.
SA8702
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1
02.02.93