ST70134 - ST70134A
ASCOT
TM
INTEGRATED ADSL CMOS
ANALOG FRONT-END CIRCUIT
s
FULLY INTEGRATED AFE FOR CPE ADSL
s
OVERALL 12 BIT RESOLUTION, 1.1MHz
SIGNAL BANDWIDTH IN Rx
s
8.8MS/s ADC
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8.8MS/s DAC
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THD: -60dB @FULL SCALE
s
4-BIT DIGITAL INTERFACE TO/FROM THE
DMT MODEM
TQFP64
ORDERING NUMBER:
ST70134 (TQFP64)
ST70134A (TQFP64)
The ST70134 analog front end handles 2 trans-
mission channels on a balanced 2 wire intercon-
nection; a 16 to 640Kbit/s upstream transmit
channel and a 1.536Mbit/s to 8.192Mbit/s down-
stream receive channel.
This asymmetrical data transmission system uses
high resolution, high speed analog to digital and
digital to analog conversion and high order analog
filtering to reduce the echo and noise in both
receivers and transmitters.
External low noise driver and input stage used
with ST70134 guarantee low noise performances.
The filters, with a programmable cutoff frequency,
use automatic Continuous Time Tuning to avoid
time varying phase characteristic which can be of
dramatic consequence for DMT modem.
It requires few external components, uses a 3.3V
supply. It is packaged in a 64-pin TQFP in order to
reduce PCB area.
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1V FULL SCALE INPUT
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DIFFERENTIAL ANALOG I/O
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ACCURATE CONTINUOUS-TIME CHANNEL
FILTERING
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3rd & 4th ORDER TUNABLE CONTINUOUS
TIME LP FILTERS
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0.5 WATT AT 3.3V
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0.5mm HCMOS5 LA TECHNOLOGY
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64 PIN TQFP PACKAGE
DESCRIPTION
ST70134 is the Analog Front End of the STMicro-
electronics ASCOT
TM
ADSL chipset and when
coupled with ST70135A or ST70235 (DMT
modem) allows to get a T1.413 Issue 2 or G.dmt
compliant solution.
January 2001
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