Ultra Low Power, Adaptive Linear Power™,
Dual-Port ADSL2+/VDSL2 Line Driver
ADLD8404
Preliminary Technical Data
FEATURES
VCC
Two differential DSL channels comprised of current
feedback, high output current amplifiers with integrated
resistors and biasing network
Ideal for use as ADSL2+/VDSL2 dual-channel Central Office
(CO) & FTTX (Remote Cabinet) line drivers
Low power consumption using Class H Technology
Single +14V supply operation
INP
+
_
VOPA
20.4 dBm line power, 1:1.4 transformer
780 mW/channel total power dissipation while driving
20.4 dBm (includes 110mW line power)
475 mW/channel total power dissipation while driving
14.5 dBm (includes line power)
VOCM
_
VONA
High output voltage and current drive
40 V p-p differential output voltage
+
INN
Low distortion
-65 dBc typical MTPR @ 20.4 dBm, 26 kHz to 2.2 MHz
-55 dBc typical MTPR @ 14.5 dBm, 5.2MHz to 17.6MHz
Low cost protection components enable K20 & GR1089
compliance
Figure 1. Channel 1 Internal Schematics
Protected by US Patent 6,636,103
APPLICATIONS
ADSL2+/VDSL2 CO line drivers
ADSL2+/VDSL2 FTTX line drivers
20
GENERAL DESCRIPTION
17.5
The ADLD8404 is comprised of two differential, high output
current, low power consumption operational amplifiers. It is
particularly well suited for the CO & FTTX driver interface in
digital subscriber line systems, such as ADSL2+ and VDSL2.
The driver can deliver 20.4 dBm to a line while compensating
for losses due to hybrid insertion and back-termination
resistors. ADLD8404 uses second- generation Adaptive Linear
Power (Class H) architecture to achieve unprecedented power
efficiency while using a single power supply and three external
capacitors. Further functionality permits the shutdown of
pumps for enhanced power savings for line power < 14.5dBm.
This yields the smallest PCB footprint and lowest total cost of
ownership.
15
12.5
10
7.5
5
2.5
0
-2.5
-5
462.75 463.5 464.25 465
465.75
The low power consumption, high output current, high output
voltage swing, and robust thermal packaging enable the
ADLD8404 to be the CO or FTTX line driver in ADSL2+ and
VDSL2 systems.
time, x1e-6 Seconds
Figure 2. Class H Operation- red & green traces are internal signal-tracking
power supplies. Channel 1 (blue, black) = ADSL2+, Channel 2 (pink, light
blue) = Profile 8b.
The ADLD8404 is available in a 4 mm × 4mm 24 lead LFCSP.
Rev. PrA
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. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registeredtrademarks arethe property of their respective owners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
Fax: 781.461.3113
www.analog.com
©2010 Analog Devices, Inc. All rights reserved.