Rail-to-Rail Upstream ADSL Line Driver
FEATURES
Dual op amp
Voltage feedback
Wide supply range: From 3.3 V to 24 V
Rail-to-rail output
Output swing to within 0.5 V of supply rails @ 230 mA
23 V p-p differential, R
High output current
Linear output current of 230 mA peak into 25 Ω
−68 dBc MTPR @ 15 dBm (100 Ω telephone line)
Low noise
4.5 nV/√Hz voltage noise density @ 100 kHz
1.5 pA/√Hz current noise density @ 100 kHz
High speed
65 MHz bandwidth (A
55 V/µs slew rate (R
APPLICATIONS
Consumer xDSL modems
Twisted pair line drivers
ADSL CPE applications
(Drop in replacement for TS613ID and EL1519CS)
Audio applications
of 50 Ω from 12 V supply
LOAD
= 1, −3 dB)
V
= 25 Ω)
LOAD
PIN CONFIGURATION
OUT1
1
–IN1
2
+IN1
3
4
–V
S
Figure 1. 8-Lead SOIC
10
0
–10
–20
–30
–40
dBm
–50
–60
–70
–80
–90
CENTER 86.31174378kHz 1kHz/ SPAN 10kHz
Figure 2. AD45048AR Upstream ADSL MTPR (13 dBm, CF = 5.3)
–68dB
+V
8
S
OUT2
7
6
–IN2
5
+IN2
AD45048
04817-Sp0-001
04817-Sp0-002
GENERAL DESCRIPTION
The AD45048 ADSL CPE line driver is a dual operational
amplifier capable of driving high output current (230 mA) and
features a rail-to-rail output stage that swings to within 0.5 V of
the supply rails. The AD45048 rail-to-rail output stage surpasses
the output voltage capability of typical emitter-follower output
stages and can deliver up to 23 V p-p differentially from a single
12 V supply in ADSL CPE line driving applications. The low
distortion, high output current, and wide output dynamic range
make the AD45048 ideal for driving upstream signals in ADSL
CPE applications.
Fabricated with ADI’s high speed XFCB-HV (eXtra Fast
Complementary Bipolar-High Voltage) process, the high
bandwidth and fast slew rate of the AD45048 keep distortion to
a minimum while dissipating minimum power. The AD45048 is
available in a standard 8-lead SOIC package that can operate
from −40°C to +85°C.
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.
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
registered trademarks are the property of their respective owners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
Fax: 781.326.8703 © 2004 Analog Devices, Inc. All rights reserved.
www.analog.com
AD45048
TABLE OF CONTENTS
Specifications..................................................................................... 3
Layout Considerations..................................................................7
Absolute Maximum Ratings............................................................ 4
ESD Caution.................................................................................. 4
Typical Performance Characteristics............................................. 5
General Description......................................................................... 7
Power Supply and Decoupling.................................................... 7
REVISION HISTORY
7/04—Revision 0: Initial Version
CPE ADSL Application.................................................................7
Transformer Sel ecti on ..................................................................7
Receive Channel Considerations.................................................7
Outline Dimensions..........................................................................8
Ordering Guide .............................................................................8
Rev. 0 | Page 2 of 8
AD45048
SPECIFICATIONS
VS = ±6 V or 12 V (@ TA = 25°C, G = +10, RL = 100 Ω, unless otherwise noted).
Table 1.
Parameter Test Conditions/Comments Min Typ Max Unit
DYNAMIC PERFORMANCE
−3 dB Bandwidth G = +1, V
0.1 dB Flatness V
Large Signal Bandwidth V
Large Signal Slew Rate V
OUT
OUT
OUT
NOISE/DISTORTION PERFORMANCE
Distortion (Worst Harmonic) fC = 40 kHz, V
Multitone Power Ratio 26 kHz to 134 kHz, Z
Input Voltage Noise f = 100 kHz 4.5 nV/√Hz
Input Current Noise f = 100 kHz 1.5 pA/√Hz
DC PERFORMANCE
Input Offset Voltage 1 2.5 mV
T
MIN
− T
Input Offset Voltage Match 1 2.0 mV
Input Bias Current 200 900 nA
T
MIN
− T
Input Offset Current 50 300 nA
Open-Loop Gain 85 94 dB
INPUT CHARACTERISTICS
Input Resistance f = 100 kHz 87 kΩ
Input Capacitance 1.4 pF
OUTPUT CHARACTERISTICS
Output Resistance 1.4 MHz; G = +1 0.2 Ω
Output Voltage Swing Maximum Swing (Differential) V
Minimum Swing (Differential) V
Differential Output Voltage Swing ∆V
Single-Ended +Swing R
Single-Ended -Swing R
Single-Ended +Swing R
Single-Ended –Swing R
OUT
LOAD
LOAD
LOAD
LOAD
Operating Range (Dual Supply) ±1.5 ±12.6 V
Supply Current 7 9 12 mA
Power Supply Rejection Ratio ±0.5 V −85 −75 dB
Common-Mode Rejection Ratio ±1 V −86 −79 dB
= 0.1 V p-p, RFB = 0 Ω, R
OUT
= 0.1 V p-p Single-Ended, G = +1, R
= 1 V p-p Single-Ended, G = +10, R
= 5 V p-p, G = +1, R
= 6 V p-p, Single-Ended, R
OUT
LINE
MAX
MAX
= V
− V
OMAX
OMIN
= 25 Ω 55 V/µs
LOAD
= 100 Ω, XFMR = 1:2 turns, P
= 25 Ω 65 MHz
LOAD
= 25 Ω 3.35 MHz
LOAD
= 25 Ω 4.5 MHz
LOAD
= 25 Ω −80 dBc
LOAD
= 13 dBm −68 dBc
LINE
2.5 mV
1.3 µA
, R
OMAX
OMIN
= 50 Ω Differential +11.25 +11.5 V diff
LOAD
, R
= 50 Ω Differential −11.5 −11.25 V diff
LOAD
22.5 23 V p-p
= 25 Ω +5.68 +5.76 Vp
= 25 Ω −5.67 −5.58 V
= 100 Ω +5.92 +5.95 V
= 100 Ω −5.91 −5.86 V
p
p
p
Rev. 0 | Page 3 of 8