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Rockwell SoniCrafter BT8960 User Manual

Bt8960, Single-chip 2b1q transceiver

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Bt8960

Single-Chip 2B1Q Transceiver

The Bt8960 is a full-duplex 2B1Q transceiver based on Rockwell’s HDSL technol-
ogy. It supports Nx64 kbps transmission of more than 18,000 feet

over 26 AWG

copper telephone wire without repeaters. Small size and low power dissipation
make the Bt8960 ideal for line-powered voice pairgain systems capable of provid-
ing four or six clear 64 kbps channels.

The Bt8960 is a highly integrated device that includes all of the active circuitry

needed for a complete 2B1Q transceiver. In the receive portion of the Bt8960, a
variable gain amplifier optimizes the signal level according to the dynamic range
of the analog-to-digital converter. Once the signal is digitized, sophisticated adap-
tive echo cancellation, equalization, and detection DSP algorithms reproduce the
originally transmitted far-end signal.

In the transmitter, the transmit source and scrambler operation is programma-

ble via the microcomputer interface. A highly linear digital-to-analog converter
with programmable gain, sets the transmission power for optimal performance. A
pulse-shaping filter and a low distortion line driver generate the signal character-
istics needed to drive a large range of subscriber lines at low-bit error rates.

Startup and performance monitoring operations are controlled via the micro-

processor interface. C-language source code supporting these operations is sup-
plied under a no-fee license agreement from Rockwell. The Bt8960 includes a
glueless interface to both Intel and Motorola microprocessors.

Functional Block Diagram

Distinguishing Features

Single-chip 2B1Q transceiver solution

All 2B1Q transceiver functions inte-
grated into a single monolithic device
– Receiver gain control and A/D

converter

– DSP functions including echo

cancellation, equalization, timing
recovery, and symbol detection

– Programmable gain transmit DAC,

pulse-shaping filter and line driver

Supports operation from 160 to 416
kbps

Capable of transceiving over the ANSI
T1.601 and ETSI ETR 080 ISDN
test loops

Flexible Monitoring and Control
– Glueless interface to Intel 8051 and

Motorola 68302 processors

– Access to embedded filters, perfor-

mance meters and timers

Backwards compatible with Bt8952
software API commands

JTAG/IEEE Std 1149.1-1990
compliant

Single +5 V power supply
operation

600 mW power consumption at 288
kbps (typical)

100-pin PQFP package

–40˚C to +85˚C operation

Applications

Voice/data pairgain systems

Internet connectivity

ISDN basic-rate interface
concentrators

ISDN H0 transport

Extended range fractional T1/E1

Cellular/microcellular base stations

Personal Communications Systems
(PCS) radio ports and cell switches

Analog

Receive

MPU

Bus

Analog

Transmit

Variable

Gain

Amplifier

Microcomputer

Interface

Line

Driver

Pulse-

Shaping

Filter

Program-

mable

Gain
DAC

Analog-

to-Digital

Converter

Digital
Signal

Processor

Framer/

Channel

Unit

Interface

Recovered
Data and
Clock

Transmit
Data

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