zl50073 Zarlink Semiconductor, zl50073 Datasheet - Page 16

• Manufacturer Part Number: zl50073
• Description: 32 K Channel Digital Switch With High Jitter Tolerance, Rate Conversion Per Group Of 4 Streams 8, 16, 32 Or 64 Mbps
• Manufacturer: Zarlink Semiconductor

1.3
The ZL50073 is a large switch with a comprehensive list of user configurable, ’per-group’ programmable features.
In order to facilitate ease of use, the ZL50073 offers a simple programming model. Streams are grouped in sets of
four, with each group sharing the same configured characteristics. In this way it is possible to reduce programming
complexity, while still maintaining flexible ’per-group’ configuration options:
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The streams are grouped, one from the TDM ’A’ streams, combined with the corresponding ’B’, ’C’ and ’D’ streams.
For example, input stream group #12 is STiA12, STiB12, STiC12, STiD12, and output stream group #4 is SToA4,
SToB4, SToC4, SToD4. There are 32 input and 32 output groups. Depending on the data rate set for the group
there will be between 1 and 4 streams activated. If the data rate is set for 65.536 Mbps, the ‘A’ stream will be
activated and the ‘B’, ‘C’ and ‘D’ streams will not be activated. If the data rate is set for 32.768 Mbps, the ‘A’ and ‘B’
streams will be activated and the ‘C’ and ‘D’ streams will not be activated. If the data rate is set for either
16.384 Mbps or 8.192 Mbps all of the streams, ‘A’, ‘B’, ‘C’ and ‘D’ will be activated. The maximum channel capacity
of a group is 1024 channels when operating at any data rate except for 8.192 Mbps, in which case the maximum
operating channel capacity decreases to 512 channels.
1.4
Table 1 shows the maximum number of streams available at different bit rates. The ZL50073 deactivates unused
streams when operating at the higher bit rates as shown in Table 2.
For 65 Mbps operation, only those inputs and outputs in the TDM ’A’ streams are active. For 32 Mbps operation,
only those inputs and outputs in the TDM ’A’ and ’B’ streams are active. For 16 Mbps and 8 Mbps, inputs and
outputs in TDM ’A’, ’B’, ’C’ and ’D’ streams are active.
Note that if the internal system clock is not used as the clock source, there are limitations on the maximum data
rate. See Section 2.0 for more details.
1.4.1
See Section 14.4, Group Control Registers, for programming details. The data rates are set with the Input Stream
Bit Rate (bits 3 - 2) and the Output Stream Bit Rate (bits 19 - 18) in the Group Control Registers 0 - 31 (GCR0 - 31)
For the ZL50073, the bit rates of the inputs and outputs are programmed independently, in groups of 4 streams.
Depending on the rate programmed, the active streams in the group will be as indicated in Table 2.
Input and output rate selection; see Section 1.4
Input stream clock source selection; see Section 2.0
Output stream clock source selection; see Section 2.0
Input stream sampling point selection; see Section 5.1
Output stream fractional bit advance; see Section 5.2
Input and output stream inversion control; see Section 14.4
Stream Provisioning
Input and Output Rate Selection
Per Group Rate Selection
Input or Output Group n
STiCn / SToCn
STiDn / SToDn
STiAn / SToAn
STiBn / SToBn
(n = 0 - 31)
Table 2 - TDM Stream Bit Rates
Not Active
Not Active
Not Active
65 Mbps
Active
Zarlink Semiconductor Inc.
ZL50073
16
Not Active
Not Active
32 Mbps
Active
Active
16 Mbps
Active
Active
Active
Active
8 Mbps
Active
Active
Active
Active
Data Sheet