TP3406 DASL Digital Adapter for Subscriber Loops
November 1992
TP3406
DASL Digital Adapter for Subscriber Loops
General Description
The TP3406 is a complete monolithic transceiver for data
transmission on twisted pair subscriber loops It is built on
National’s double poly microCMOS process and requires
only a single
a
5 Volt supply Alternate Mark Inversion (AMI)
line coding in which binary ‘1’s are alternately transmitted
as a positive pulse then a negative pulse is used to ensure
low error rates in the presence of noise with lower emi radia-
tion than other codes such as Bi-phase (Manchester)
Full-duplex transmission at 144 kb s is achieved on a single
twisted wire pair using a burst-mode technique (Time Com-
pression Multiplexed) Thus the device operates as an ISDN
‘U’ Interface for short loop applications typically in a PBX
environment providing transmission for 2 B channels and 1
D channel On 24 cable the range is up to 800 meters
System timing is based on a Master Slave configuration
with the line card end being the Master which controls loop
timing and synchronisation All timing sequences necessary
for loop activation and de-activation are generated on-chip
Selection of Master and Slave mode operation is pro-
grammed via the Microwire Control Interface
A 2 048 MHz clock which may be synchronized to the sys-
tem clock controls all transmission-related timing functions
Features
Complete ISDN PBX 2-Wire Data Transceiver including
Y
2 B plus D channel interface for PBX U Interface
Y
144 kb s full-duplex on 1 twisted pair using Burst Mode
Y
Loop range up to 800 meters (
24AWG)
Y
Alternate Mark Inversion coding with transmit filter and
scrambler for low emi radiation
Y
Adaptive line equalizer
Y
On-chip timing recovery no external components
Y
Standard TDM interface for B channels
Y
Separate interface for D channel
Y
2 048 MHz master clock
Y
Driver for line transformer
Y
4 loop-back test modes
Y
Single
a
5V supply
Y
MICROWIRE
TM
compatible serial control interface
Y
Applications in
PBX Line Cards
Terminals
Regenerators
Y
Available in 28-pin PLCC Package
Block Diagram
TL H 11725 – 1
TRI-STATE is a registered trademark of National Semiconductor Corporation
MICROWIRE
TM
is a trademark of National Semiconductor Corporation
C
1995 National Semiconductor Corporation
TL H 11725
RRD-B30M115 Printed in U S A
NSC [ NATIONAL SEMICONDUCTOR ]
