|
Features
Complete ISDN PBX 2-Wire Data Transceiver including:
2 B plus D channel interface for PBX U[Foot][Minute][Prime] Interface
144 kb/s full-duplex on 1 twisted pair using Burst Mode
Loop range up to 800 meters (#24AWG)
Alternate Mark Inversion coding with transmit filter and scrambler for low emi radiation
Adaptive line equalizer
On-chip timing recovery, no external components
Standard TDM interface for B channels
Separate interface for D channel
2.048 MHz master clock
Driver for line transformer
4 loop-back test modes
Single +5V supply
MICROWIRE™ compatible serial control interface
Applications in: PBX Line Cards Terminals Regenerators
Available in 28-pin PLCC Package
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 +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 radiation 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 Compression 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 programmed via the Microwire Control Interface.
A 2.048 MHz clock, which may be synchronized to the system clock, controls all transmission-related timing functions.
| 
