DS32506 Datasheet, PDF (9/130 Pages) Maxim Integrated Products – 6-/8-/12-Port DS3/E3/STS-1 LIU

DS32506/DS32508/DS32512
4. DETAILED DESCRIPTION
The DS32506 (6 port), DS32508 (8 port), and DS32512 (12 port) LIUs perform the functions necessary for
interfacing at the physical layer to DS3, E3, or STS-1 lines. Each LIU has independent receive and transmit paths
and a built-in jitter attenuator. The receiver performs clock and data recovery from a B3ZS- or HDB3-coded
alternate mark inversion (AMI) signal and monitors for loss of the incoming signal. The receiver optionally performs
B3ZS/HDB3 decoding and outputs the recovered data in either binary (NRZ) or digital bipolar format. The
transmitter accepts data in either binary (NRZ) or digital bipolar format, optionally performs B3ZS/HDB3 encoding,
and drives standard pulse-shape waveforms onto 75Ω coaxial cable. Both transmitter and receiver are high-
impedance when V_DD is out of spec to enable hot-swappable 1:1 and 1+1 board redundancy without relays. The
jitter attenuator can be mapped into the receiver data path, mapped into the transmitter data path, or disabled. An
on-chip clock adapter generates all line-rate clocks from a single input clock. Control interface options include 8- or
16-bit parallel, SPI, and hardware mode. The DS325xx LIUs conform to the telecommunications standards listed in
Table 1-1. The external components required for proper operation are shown in Figure 4-1 and Figure 4-2.
Figure 4-1. External Connections, Internal Termination Enabled
TXP
TXP
TVDD
0.01μF 0.1μF 1μF
1.8V
RVDD
0.01μF 0.1μF 1μF
POWER
PLANE
1:1
TXN
TXN
JVDD
0.01μF 0.1μF 1μF
RXP
TVSS
RVSS
RXN
JVSS
1:1
GROUND
PLANE
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