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AD8391 Datasheet, PDF (1/20 Pages) Analog Devices – xDSL Line Driver 3 V to 12 V with Power-Down
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FEATURES
Ideal xDSL Line Driver for VoDSL or Low Power
Applications such as USB, PCMCIA, or PCI-Based
Customer Premise Equipment (CPE)
High Output Voltage and Current Drive
340 mA Output Drive Current
Low Power Operation
3 V to 12 V Power Supply Range
1-Pin Logic Controlled Standby, Shutdown
Low Supply Current of 19 mA (Typical)
Low Distortion
–82 dBc SFDR, 12 V p-p into Differential 21 ⍀ @ 100 kHz
4.5 nV/√Hz Input Voltage Noise Density, 100 kHz
Out-of-Band SFDR = –72 dBc, 144 kHz to 500 kHz,
ZLINE = 100 ⍀, PLINE = 13.5 dBm
High Speed
40 MHz Bandwidth (–3 dB)
375 V/␮s Slew Rate
APPLICATIONS
VoDSL Modems
xDSL USB, PCI, PCMCIA Cards
Line Powered or Battery Backup xDSL Modems
xDSL Line Driver
3 V to 12 V with Power-Down
AD8391
PIN CONFIGURATION
8-Lead SOIC
(Thermal Coastline)
IN1 1
؊VS
VMID
؉VS
PWDN 2
؊؉
+VS 3
؉؊
VOUT1 4
AD8391
8 IN2
7 VMID
6 –VS
5 VOUT2
PRODUCT DESCRIPTION
The AD8391 consists of two parallel, low cost xDSL line drive
amplifiers capable of driving low distortion signals while running on
both 3 V to 12 V single-supply or equivalent dual-supply rails. It is
primarily intended for use in single-supply xDSL systems where low
power is essential, such as line powered and battery backup systems.
Each amplifier output drives more than 250 mA of current while
maintaining –82 dBc of SFDR at 100 kHz on 12 V, outstanding
performance for any xDSL CPE application.
The AD8391 provides a flexible power-down feature consisting of
a 1-pin digital control line. This allows biasing of the AD8391 to
full power (Logic “1”), Standby (Logic “tri-state” maintains low
amplifier output impedance), and Shutdown (Logic “0” places
amplifier outputs in a high impedance state). PWDN is refer-
enced to –VS.
Fabricated on ADI’s high-speed XFCB process, the high bandwidth
and fast slew rate of the AD8391 keep distortion to a minimum,
while dissipating a minimum of power. The quiescent current of the
AD8391 is low; 19 mA total static current draw. The AD8391
comes in a compact 8-lead SOIC “Thermal Coastline” package, and
operates over the temperature range –40°C to +85°C.
EMPTY BIN
25
137.5
250
FREQUENCY – kHz
Figure 1. Upstream Transit Spectrum with Empty Bin
at 45 kHz; Line Power = 12.5 dBm into 100 Ω
REV. 0
Information furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assumed by Analog Devices for its
use, nor for any infringements of patents or other rights of third parties that
may result from its use. No license is granted by implication or otherwise
under any patent or patent rights of Analog Devices.
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Tel: 781/329-4700
www.analog.com
Fax: 781/326-8703
© Analog Devices, Inc., 2001