ST70136 Datasheet, PDF (1/24 Pages) STMicroelectronics – CPE ADSL ANALOG FRONT END

ST70136
CPE ADSL ANALOG FRONT END
s WIDE TRANSMIT AND RECEIVE DYNAMIC
RANGE TO REDUCE EXTERNAL
FILTERING REQUIREMENTS
s RECEIVE PROGRAMMABLE GAIN: 0 TO
31dB GAIN IN 1dB STEPS
s RECEIVE PROGRAMMABLE ATTENUATOR
0,-4dB, -8dB, -12dB
s 12-BIT A/D CONVERTER IN RECEIVE PATH
s TRANSMIT PROGRAMMABLE GAIN: 0 TO
-15dB IN 1dB STEPS
s 14-BIT D/A CONVERTER IN TRANSMIT PATH
s LOW POWER MODE: 10mW IN LISTENING
MODE, 250µW IN POWER DOWN
s TONE DETECTOR: ACTIVITY DETECTION
FOR WAKE-UP FUNCTION
s 64-PIN TQFP PACKAGE
s 64-PIN LFBGA PACKAGE
s 0.50µm, 5V BICMOS TECHNOLOGY
s 3.3V DIGITAL INTERFACE
s 5V ANALOG INTERFACE
INTRODUCTION
The ST70136 ADSL Analog Front End (AFE) chip
implements the analog transceiver functions
required in a Customer Premise ADSL modem. It
connects the digital modem chip with the loop
driver and hybrid balance circuits.
The AFE has been designed with high dynamic
range in order to greatly reduce the external filter-
ing requirements at the front end.
The AFE chip and its companion digital chip along
with a loop driver, implement the complete
G.992.2 and G.992.1 DMT modem solution.
Figure 1 : Overall Application Block Diagram
Software for Control xDSL
The AFE receive path contains a programmable
gain amplifier (RxPGA), a low pass anti-aliasing
filter, and a 12-bit A/D converter. The RxPGA is
digitally programmable from 0 to 31dB in 1dB
steps.
The AFE transmit path consists of a 14-bit D/A
converter, followed by a programmable gain
amplifier (TxPGA). The transmit gain is program-
mable from 0 to -15dB in 1dB steps.
TQFP64 Full Plastic
(10 x 10 x 1.40 mm)
ORDER CODE: ST70136G
LFBGA64
(8 x 8 x 1.7 mm)
ORDER CODE: ST70136B
PCI
PC
or
USB
PCI
or
USB
DMT
ST70137
xDSL
AFE
ST70136
LOOP
DRIVER
HYBRID
TS612/TS652
LINE
September 2001
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