参数资料
型号: LXT361LE
英文描述: Telecommunication IC
中文描述: 通信集成电路
文件页数: 13/52页
文件大小: 1187K
代理商: LXT361LE
Integrated T1/E1 LH/SH Transceiver for DS1/DSX-1 or PRI Applications
LXT361
Datasheet
13
3.0
Functional Description
The LXT361 is a fully integrated, PCM transceiver for Long- or Short-Hual, 1.544 Mbps (T1) or
2.048 Mbps (E1) applications allowing full-duplex transmission of digital data over existing
twisted-pair installations. The device interfaces with two twisted-pair lines (one pair each for
transmit and receive) through standard pulse transformers and appropriate resistors.
The figure on the front page of this data sheet shows a block diagram of the LXT361. Control of
the chip is via the 8-bit parallel microprocessor port. Stand-alone operation is not supported.
The LXT361 provides a high-precision, crystal-less Jitter Attenuator (JA). The user may place the
JA in the transmit or receive path, or bypass it completely.
The transceiver meets or exceeds FCC, ANSI, and AT&T specifications for CSU and DSX-1
applications, as well as ITU and ETSI requirements for E1 ISDN PRI applications.
3.1
Initialization
During power up, the transceiver remains static until the power supply reaches approximately 3 V.
Upon crossing this threshold, the device begins a 32 ms reset cycle to calibrate the Phase Lock
Loops (PLL). The transceiver uses a reference clock to calibrate the PLLs: the transmitter reference
is TCLK, and the receiver reference clock is MCLK. MCLK is mandatory for chip operation and
must be independent, free running, and jitter free.
3.1.1
Reset Operation
A reset operation initializes the status and state machines for the LOS, AIS, NLOOP, and QRSS
blocks. Writing a 1 to the bit CR2.RESET commands a reset which clears all registers to 0. Allow
32 ms for the device to settle.
3.2
Transmitter
3.2.1
Transmit Digital Data Interface
Input data for transmission onto the line is clocked serially into the device at the TCLK rate. TPOS
and TNEG are the bipolar data inputs. In Unipolar mode, the TDATA pin accepts unipolar data.
Input data may pass through either the Jitter Attenuator or B8ZS/HDB3 encoder or both. Setting
CR1.ENCENB = 1 enables B8ZS/HDB3 encoding. With zero suppression enabled, Control
Register #1 (CR1) bits EC1 through EC4 determine the coding scheme as listed in
Table 8 on
page 27
.
TCLK supplies input synchronization. See the
Figure 14 on page 41
for the transmit timing
requirements for TCLK and the Master Clock (MCLK).
相关PDF资料
PDF描述
LXT361PE Telecommunication IC
LXT362LE PCM TRANSCEIVER|SINGLE|T-1(DS1)|CMOS|QFP|44PIN|PLASTIC
LXT362PE PCM TRANSCEIVER|SINGLE|T-1(DS1)|CMOS|LDCC|28PIN|PLASTIC
LXT362QE PCM TRANSCEIVER|SINGLE|T-1(DS1)|CMOS|QFP|44PIN|PLASTIC
LXT363LE PCM TRANSCEIVER|SINGLE|T-1(DS1)|CMOS|QFP|44PIN|PLASTIC
相关代理商/技术参数
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LXT361PE 制造商:LEVEL 1 功能描述: 制造商:LEVEL ONE 功能描述: 制造商:Intel 功能描述:PCM TRANSCEIVER, Single, CEPT PCM-30/E-1, 28 Pin, Plastic, PLCC
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LXT362 制造商:INTEL 制造商全称:Intel Corporation 功能描述:Integrated T1 LH/SH Transceiver for DS1/DSX-1 or PRI Applications
LXT362LE 制造商:未知厂家 制造商全称:未知厂家 功能描述:PCM TRANSCEIVER|SINGLE|T-1(DS1)|CMOS|QFP|44PIN|PLASTIC
LXT362PE 制造商:未知厂家 制造商全称:未知厂家 功能描述:PCM TRANSCEIVER|SINGLE|T-1(DS1)|CMOS|LDCC|28PIN|PLASTIC