ZL50022
Data Sheet
Description
The ZL50022 is a maximum 4,096 x 4,096 channel non-blocking digital Time Division Multiplex (TDM) switch. It has
thirty-two input streams (STi0 - 31) and thirty-two output streams (STio0 - 31). The device can switch 64 kbps and
Nx64 kbps TDM channels from any input stream to any output stream. Each of the input and output streams can be
independently programmed to operate at any of the following data rates: 2.048 Mbps, 4.096 Mbps, 8.192 Mbps or
16.384 Mbps. The ZL50022 provides up to sixteen high impedance control outputs (STOHZ0 - 15) to support the
use of external tristate drivers for the first sixteen output streams (STio0 - 15). The output streams can be
configured to operate in bi-directional mode, in which case STi0 - 31 will be ignored.
The device contains two types of internal memory - data memory and connection memory. There are four modes of
operation - Connection Mode, Message Mode, BER mode and high impedance mode. In Connection Mode, the
contents of the connection memory define, for each output stream and channel, the source stream and channel
(the actual data to be output is stored in the data memory). In Message Mode, the connection memory is used for
the storage of microprocessor data. Using Zarlink's Message Mode capability, microprocessor data can be
broadcast to the data output streams on a per-channel basis. This feature is useful for transferring control and
status information for external circuits or other TDM devices. In BER mode the output channel data is replaced with
a pseudo-random bit sequence (PRBS) from one of 32 PRBS generators that generates a 215-1 pattern. On the
input side channels can be routed to one of 32-bit error detectors. In high impedance mode the selected output
channel can be put into a high impedance state.
When the device is operating as a timing master, the internal digital PLL is in use. In this mode, an external
20.000 MHz crystal is required for the on-chip crystal oscillator. The DPLL is phase-locked to one of four input
reference signals (which can be 8 kHz, 1.544 MHz, 2.048 MHz, 4.096 MHz, 8.192 MHz, 16.384 MHz or 19.44 MHz
provided on REF0 - 3). The on-chip DPLL operates in normal, holdover or freerun mode and offers jitter
attenuation. The jitter attenuation function exceeds the Stratum 4E specification.
The configurable non-multiplexed microprocessor port allows users to program various device operating modes
and switching configurations. Users can employ the microprocessor port to perform register read/write, connection
memory read/write, and data memory read operations. The port is configurable to interface with either Motorola or
Intel-type microprocessors.
The device also supports the mandatory requirements of the IEEE-1149.1 (JTAG) standard via the test port.
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Zarlink Semiconductor Inc.