zl50031 Zarlink Semiconductor, zl50031 Datasheet - Page 12

• Manufacturer Part Number: zl50031
• Description: Flexible 4 K X 2 K Channel Digital Switch With H.110 Interface And 2 K X 2 K Local Switch
• Manufacturer: Zarlink Semiconductor

1.0
The ZL50031 can switch up to 4,096 × 2,048 channels while providing a rate conversion capability. It is designed to
switch 64 kbps PCM or N X 64 kbps data between the backplane and local switching applications. The device
maintains frame integrity in data applications and minimum throughput delay for voice applications on a per-
channel basis.
The backplane interface can operate at 8.192 Mbps in CT-Bus mode or 16.384 Mbps in ST-BUS mode and is
arranged in 125 µs wide frames that contain 128 or 256 channels respectively. A built-in rate conversion circuit
allows users to interface between the backplane and the local interface which operates at 2.048 Mbps, 4.096 Mbps
or 8.192 Mbps.
By using Zarlink’s message mode capability, the microprocessor can access input and output time slots on a per
channel basis. This feature is useful for transferring control and status information for external circuits or other TDM
devices.
2.0
A Functional Block Diagram of the ZL50031 is shown in Figure 1 on page 2. It is designed to interface CT-Bus and
ST-BUS serial streams from a backplane source and ST-BUS serial streams from a local source.
3.0
In the ST-BUS or the CT-Bus mode, the C8_A_io or C8_B_io pin accepts an 8.192 MHz clock for the frame pulse
alignment. The FRAME_A_io or FRAME_B_io is the frame pulse signal which goes low at the frame boundary for
122 ns. The frame boundary is defined by the rising edge of the C8_A_io or C8_B_io clock during the low cycle of
the frame pulse. Figure 2 shows the CT-Bus timing for the backplane 8.192 Mbps data streams and Figure 3 shows
the ST-BUS timing for the 16.384 Mbps backplane data streams.
(8 Mbps mode)
(CT Frame)
(8.192 MHz)
FRAME_B_io
FRAME_A_io,
BSTio 0 - 31
Device Overview
Functional Description
Frame Alignment Timing
C8_A_io,
C8_B_io
1
Figure 2 - CT-Bus Timing for 8 Mbps Backplane Data Streams
0
7
6
5
Channel 0
4
Zarlink Semiconductor Inc.
3
ZL50031
2
1
12
0
6
5
Channel 127
4
3
2
1
0
Data Sheet
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