ZL50030 Datasheet, PDF (17/73 Pages) Zarlink Semiconductor Inc – Flexible 4 K x 2 K Channel Digital Switch with H.110 Interface and 1 K x 1 K Local Switch

ZL50030
Data Sheet
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BBPD2 BBPD1 BBPD0 0
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Backplane Connection Memory (BCM)
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LBPD2 LBPD1 LBPD0 0
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Local Connection Memory (LCM)
Figure 4 - Block Programming Data in the Connection Memories
9.0 Delay Through the ZL50030
The switching of information from the input serial streams to the output serial streams results in a throughput delay.
The device can be programmed to perform time slot interchange functions with different throughput delay
capabilities on a per-channel basis. For voice applications it is recommended to select variable throughput delay to
ensure minimum delay between input and output data. In wideband data applications it is recommended to select
constant throughput delay to maintain the frame integrity of the information through the switch.
The delay through the device varies according to the type of throughput delay selected in the BTM2 - BTM0 bits of
the backplane connection memory or LTM0 - LTM2 bits of the local connection memory as described in Table 24 on
page 51 and Table 27 on page 53, respectively.
9.1 Variable Delay Mode
The delay in this mode is dependent only on the combination of source and destination channels and is
independent of input and output streams. The minimum delays achievable in the ZL50030 device are 3-channel
delay, 5-channel delay, and 10-channel delay for the 2 Mbps, 4 Mbps, and 8 Mbps data rates respectively. The
maximum delay is one frame plus 3 channels, one frame plus 5 channels, and one frame plus 10 channels for the
2 Mbps, 4 Mbps and 8 Mbps modes respectively.
For the backplane interface, the variable delay mode can be programmed through the backplane connection
memory bits, BTM2 - BTM0. When BTM2 - BTM0 are programmed to “000”, it is a per-channel variable delay from
local input to the backplane output. When BTM2 - BTM0 are set to “010”, it is a per-channel variable delay from
backplane input to backplane output.
For the local interface, the variable delay mode can be programmed through the local connection memory bits,
LTM2 - LTM0. When LTM2 - LTM0 are programmed to “000”, it is a per-channel variable delay from local input to
local output. When LTM2 - LTM0 are set to “010”, it is a per-channel variable delay from backplane input to local
output.
9.2 Constant Delay Mode
In this mode, a multiple page data memory buffer is used to maintain frame integrity in all switching configurations
such that a channel written during frame N is always read out during frame N+2.
For the backplane interface, when BTM2 - BTM0 are programmed to “001”, it is a per-channel constant delay mode
from local input to backplane output. When BTM2 - BTM0 are set to “011”, it is a per-channel constant delay mode
from backplane input to backplane output.
For the local interface, when LTM2 - LTM0 are programmed to “001”, it is a per-channel constant delay mode from
local input to local output. When LTM2 - LTM0 are set to “011”, it is a per-channel constant delay mode from
backplane input to local output.
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Zarlink Semiconductor Inc.