CS61884
Octal T1/E1/J1 Line Interface Unit
Features
Industry-standard Footprint
Octal E1/T1/J1 Short-haul Line Interface Unit
Low Power
No external component changes for
100
Ω/120 Ω/75 Ω
operation.
Pulse shapes can be customized by the user.
Internal AMI, B8ZS, or HDB3 Encoding/Decoding
LOS Detection per T1.231, ITU G.775, ETSI 300-233
G.772 Non-Intrusive Monitoring
G.703 BITS Clock Recovery
Crystal-less Jitter Attenuation
Serial/Parallel Microprocessor Control Interfaces
Transmitter Short Circuit Current Limiter (<50mA)
TX Drivers with Fast High-Z and Power Down
JTAG boundary scan compliant to IEEE 1149.1.
144-Pin LQFP or 160-Pin BGA Package
ORDERING INFORMATION
CS61884-IQ
144-pin LQFP
CS61884-IQZ
144-pin LQFP, Lead Free
CS61884-IB
160-pin FBGA
Each receiver provides reliable data recovery with over
12 dB of cable attenuation. The receiver also incorpo-
rates LOS detection compliant to the most recent
specifications.
Description
The CS61884 is a full-featured octal E1/T1/J1 short-haul
LIU that supports both 1.544 Mbps or 2.048 Mbps data
transmission. Each channel provides crystal-less jitter
attenuation that complies with the most stringent stan-
dards. Each channel also provides internal
AMI/B8ZS/HDB3 encoding/decoding. To support en-
hanced system diagnostics, channel zero can be
configured for G.772 non-intrusive monitoring of any of
the other 7 channels’ receive or transmit paths.
The CS61884 makes use of ultra-low-power, matched-
impedance transmitters and receivers to reduce power
beyond that achieved by traditional driver designs. By
achieving a more precise line match, this technique also
provides superior return loss characteristics. Additional-
ly, the internal line matching circuitry reduces the
external component count. All transmitters have controls
for independent power down and High-Z.
LOS
Decoder
LOS
Receiver
RCLK
RPOS
RNEG
Clock
Recovery
Data
Recovery
RTIP
Analog Loopback
Remote Loopback
RRING
Digital Loopback
G.772 Monitor
Jitter
Attenuator
Driver
Transmit
Control
Pulse
Shaper
TCLK
TPOS
TNEG
TTIP
TRING
0
1
7
JTAG
Serial
Port
Encoder
JTAG Interface
Host Interface
Host
Serial/Parallel
Port
Copyright
©
Cirrus Logic, Inc. 2005
(All Rights Reserved)
AUG ‘05
DS485F1
1
CIRRUS [ CIRRUS LOGIC ]
