19-2539; Rev 2; 9/05
Low-Power, Low-Distortion, Central-Office
ADSL Drivers and Integrated Drivers/Receivers
General Description
The MAX9480/MAX9481/MAX9482 low-power, low-dis-
tortion, class-G, high-current asymmetric digital sub-
scriber line (ADSL) drivers offer Rail-to-Rail
®
output and
are ideal for ADSL in central-office applications.
Operating from ±5V and ±2.5V supplies, the drivers
incorporate two high-speed current-feedback preampli-
fiers driving two fixed-gain class-G buffers. The buffers
can deliver 20.4dBm average line power with a signal
crest factor of 5.3, and are designed to be directly DC or
AC bridged across a 1:2.5 transformer.
The MAX9480/MAX9481/MAX9482 employ an active line
termination scheme for incoming signals that eliminates
the need for back-match resistors, reducing line-card
power consumption at full rate to less than half of that
required by conventional class-AB line-driver circuits.
The MAX9480 includes a hybrid network and two low-
noise, fixed-gain-of-4.6V/V receive amplifiers. The part is
designed to recover the receive signal to the same level
as that of a conventional line interface circuit that incor-
porates a 1:2 transformer and standard back-matched
hybrid, without degrading signal-to-noise ratio (SNR) or
line-impedance sensitivity. The MAX9481 provides only
the preamplifiers and buffers without the hybrid or
receivers. The MAX9482 provides preamplifiers, buffers,
and uncommitted receive amplifiers. All devices have a
low-output-impedance shutdown function for saving
power when not transmitting.
At full-rate 20.4dBm discrete multitone data transmission
(DMT), the total dynamic power dissipation is only
680mW (MAX9480/MAX9482) or 655mW (MAX9481).
The MAX9480/MAX9481 are available in a 20-pin TSSOP
package and the MAX9482 is available in 28-pin TSSOP
and 32-pin QFN packages. All devices operate over the
extended -40°C to +85°C temperature range.
Features
o
Dissipate Only 655mW While Driving 20.4dBm
ADSL Full-Rate DMT-Modulated Signal
o
Operate with ±5.0V and ±2.5V Power Supplies
o
Complete ADSL Central-Office Line Interface
(MAX9480/MAX9482)
Two Preamplifiers plus Class-G Rail-to-Rail
Buffers
Active Line Termination plus Integrated Hybrid
(MAX9480)
Low-Noise Uncommitted Receive Amplifiers
(MAX9482)
Fixed-Gain Receive Amplifiers (MAX9480)
Low-Output-Impedance Shutdown Mode
o
Preamplifiers, Buffers, and Active Line
Termination Functions (MAX9481)
o
High-Output-Drive Capability
15V
P-P
Differential Output Voltage Swing at
R
L
= 16Ω
500mA Output-Drive
o
Low Distortion: -71dBc Highest Harmonic at 1MHz
and 14V
P-P
o
High Speed: 250V/µs Slew Rate, 80MHz -3dB
Bandwidth (G = -3)
o
Thermal Shutdown
o
Exposed Pads Improve Thermal Performance
MAX9480/MAX9481/MAX9482
Ordering Information
PART
MAX9480EUP
MAX9481EUP
MAX9482EUI
MAX9482EGJ*
TEMP RANGE
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
PIN-PACKAGE
20 TSSOP-EP**
20 TSSOP-EP
28 TSSOP-EP
32 QFN
PKG
CODE
U20E-4
U20E-4
U28E-4
G3277-2
Applications
Full-Rate ADSL
HDSL
Central Office
DSLAM
*Future
product—contact factory for availability.
**EP
= Exposed pad.
Pin Configurations
TOP VIEW
POUT1 1
IN1- 2
IN1+ 3
RXP 4
DGND 5
SHDN 6
RXM 7
20 V
LM
19 V
LP
18 V
CC
17 OUT1
MAX9480
16 V
EE
15 V
EE
14 OUT2
13 V
CC
12 V
LP
11 V
LM
Typical Operating Circuits appear at end of data sheet.
Rail-to-Rail is a registered trademark of Nippon Motorola, Ltd.
IN2+ 8
IN2- 9
POUT2 10
TSSOP
Pin Configurations continued at end of data sheet.
________________________________________________________________
Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
Low-Power, Low-Distortion, Central-Office
ADSL Drivers and Integrated Drivers/Receivers
MAX9480/MAX9481/MAX9482
ABSOLUTE MAXIMUM RATINGS
V
CC
to V
EE
...........................................................................+12V
V
LP
to V
LM
............................................................................+12V
V
CC
or V
LP
to DGND ................................................-0.3V to +6V
V
CC
to V
LP
................................................................-0.3V to +6V
V
EE
or V
LM
to DGND ................................................-6V to +0.3V
V
EE
to V
LM
................................................................-6V to +0.3V
Current into V
LP
or V
LM
..................................................±250mA
IN1+, IN1-, IN2+, IN2-......................(V
CC
+ 0.3V) to (V
EE
- 0.3V)
SHDN ...............................................(V
CC
+ 0.3V) to (V
EE
- 0.3V)
BOUT1/BOUT2 Output Short-Circuit Duration to
V
CC
/V
EE
/V
LP
/V
LM
....................................................Momentary
BOUT1/BOUT2 Output Current...........................................20mA
OUT1/OUT2 Output Short-Circuit Duration to
V
CC
/V
EE
/V
LP
/V
LM
....................................................Momentary
OUT1/OUT2 Output Current ....................................................1A
OUT1 to OUT2 Short-Circuit Duration ........................Continuous
POUT1/POUT2 Output Short-Circuit Duration to
V
CC
/V
EE
/V
LP
/V
LM
................................................................10s
POUT1/POUT2 Output Current .........................................100mA
RXP/RXM Output Short-Circuit Duration to
V
CC
/V
EE
/V
LP
/V
LM
................................................................10s
RXP/RXM Output Current..................................................100mA
Continuous Power Dissipation (T
A
= +70°C)
20-Pin TSSOP with Pad Connected to V
EE
(derate 21.7mW/°C above +70°C) ..............................1739mW
20-Pin TSSOP with Floating Pad
(derate 11.0mW/°C above +70°C) ................................879mW
28-Pin TSSOP with Pad Connected to V
EE
(derate 23.8mW/°C above +70°C) ..............................1905mW
28-Pin TSSOP with Floating Pad
(derate 12.8mW/°C above +70°C) ..............................1026mW
32-Pin QFN (derate 23.3mW/°C above +70°C) .........1860mW*
Operating Temperature Range
(T
MIN
, T
MAX
) .....................................................-40°C to +85°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
*Refer
to Application Note HFAN-08-1.
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(V
CC
= +5V, V
EE
= -5V, V
LP
= +2.5V, V
LM
= -2.5V, DGND = 0, R
L
= 16Ω is connected from OUT1 to OUT2, SHDN = 0, T
A
= T
MIN
to
T
MAX
, unless otherwise noted. Typical values specified at T
A
= +25°C. Preamp configured for A
V
= +1 with 1kΩ from POUT_ to IN_-.)
(Note 1)
PARAMETER
Dynamic Power Dissipation
SYMBOL
P
DISS
CONDITIONS
V
OUT(DIFF)
= 1.327V
RMS
,
crest factor = 5.3
MAX9480/
MAX9482
MAX9481
Dynamic Power Consumption
P
CONS
V
CC
Supply Voltage Range
V
EE
V
LP
V
LM
V
OUT(DIFF)
= 1.327V
RMS
,
crest factor = 5.3
(Note 2)
(Note 2)
(Note 2)
(Note 2)
MAX9480, R
L
=
∞
Quiescent Supply Current
(Including Preamps)
I
CC
, I
EE
,
I
LP
, I
LM
MAX9481, R
L
=
∞
MAX9482, R
L
=
∞
V
CC
, V
EE
V
LP
, V
LM
V
CC
, V
EE
V
LP
, V
LM
V
CC
, V
EE
V
LP
, V
LM
MAX9480/
MAX9482
MAX9481
4.75
-4.75
2.25
-2.25
MIN
TYP
680
655
790
765
5.00
-5.00
2.50
-2.50
21.5
22.0
20.0
21.0
21.5
22.0
5.25
-5.25
2.75
-2.75
35.0
40.0
34.0
39.0
35.0
40.0
mA
V
mW
MAX
UNITS
mW
2
_______________________________________________________________________________________
Low-Power, Low-Distortion, Central-Office
ADSL Drivers and Integrated Drivers/Receivers
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= +5V, V
EE
= -5V, V
LP
= +2.5V, V
LM
= -2.5V, DGND = 0, R
L
= 16Ω is connected from OUT1 to OUT2, SHDN = 0, T
A
= T
MIN
to
T
MAX
, unless otherwise noted. Typical values specified at T
A
= +25°C. Preamp configured for A
V
= +1 with 1kΩ from POUT_ to IN_-.)
(Note 1)
PARAMETER
SYMBOL
CONDITIONS
MAX9480, R
L
=
∞
Shutdown Supply Current
I
SD
MAX9481, R
L
=
∞
MAX9482, R
L
=
∞
Transmit Path Power-Supply
Rejection Ratio (Single Ended)
Common-Mode Rejection
Hybrid Rejection Ratio
(MAX9480 Only)
Driver-to-Receiver Crosstalk
(MAX9482 Only)
SHDN Logic Low
SHDN Logic High
SHDN Input Current
Shutdown Delay Time
Shutdown Enable Time
Intermodulation Distortion
DRIVER
Maximum RMS Output Power
(Typical
Operating Circuit)
(Note 3)
Closed-Loop Gain
Second Harmonic Distortion
Third Harmonic Distortion
Differential Output Voltage Swing
OUT_ Voltage Swing
(per Amplifier) (Note 4)
DMT modulation (crest factor, Cr = 5.33)
P
OUT
CAP modulation (crest factor, Cr = 4.00)
G
V
OUT(DIFF)
= 1.2V
P-P
f = 1MHz, V
OUT(DIFF)
= 14V
P-P
,
Typical Operating Circuit
(Note 4)
f = 1MHz, V
OUT(DIFF)
= 14V
P-P
,
Typical
Operating Circuit
(Note 4)
V
OUT(DIFF)
Typical Operating Circuit
(Note 4)
R
L
= 100Ω
V
OH
, V
OL
R
L
= 16Ω
BOUT_ Voltage Swing
(per Amplifier) (Note 4)
Peak Output Current
Differential Output Offset Voltage
V
BOH
,
V
BOL
I
OUT
V
OS(DIFF)
IN1+ = IN2+ = 0
V
CC
- V
OH
|V
EE
- V
OL
|
V
CC
- V
OH
|V
EE
- V
OL
|
V
CC
- V
BOH
|V
EE
- V
BOL
|
24.3
-2.7
-3
-71
-74
15.0
0.5
0.5
1.27
1.21
0.45
0.42
500
±5
V
mA
mV
V
-3.3
V/V
dB
dB
V
P-P
21.4
dBmW
PSRR
CMR
HRR
X
TALK
V
IL
V
IH
I
IH
, I
IL
t
SHDN
t
ENABLE
I
MD
f1 = 1MHz, f2 = 900kHz,
Typical Operating
Circuit,
V
OUT(DIFF)
= 2.0V
P-P
SHDN = 0 or SHDN = V
CC
4.8
4
-66
2.0
±5.0
V
CC
- V
EE
= ±4.75V to ±5.25V
V
LP
- V
LM
= ±2.25V to ±2.75V
-200mV
≤
V
CM
≤
+200mV
V
OUT(DIFF)
= ±1.2V
f = 100kHz
V
CC
, V
EE
V
LP
, V
LM
V
CC
, V
EE
V
LP
, V
LM
V
CC
, V
EE
V
LP
, V
LM
50
50
MIN
TYP
2.1
1.5
0.6
0.05
2.1
1.5
76
81
46
35
-69
0.8
MAX
6.0
5.0
1.2
0.1
6.0
5.0
dB
dB
dB
dB
V
V
µA
µs
µs
dB
mA
UNITS
MAX9480/MAX9481/MAX9482
_______________________________________________________________________________________
3
Low-Power, Low-Distortion, Central-Office
ADSL Drivers and Integrated Drivers/Receivers
MAX9480/MAX9481/MAX9482
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= +5V, V
EE
= -5V, V
LP
= +2.5V, V
LM
= -2.5V, DGND = 0, R
L
= 16Ω is connected from OUT1 to OUT2, SHDN = 0, T
A
= T
MIN
to
T
MAX
, unless otherwise noted. Typical values specified at T
A
= +25°C. Preamp configured for A
V
= +1 with 1kΩ from POUT_ to IN_-.)
(Note 1)
PARAMETER
Differential Output Offset-Voltage
Drift
Output Resistance (per Amplifier)
-3dB Bandwidth
Slew Rate
Output Noise PSD
Capacitive Load Stability
PREAMPS AND RECEIVERS
(Note 5)
Open-Loop Transimpedance
Power-Supply Rejection Ratio
Input Offset Voltage
IN1+, IN2+, RXIN1+, RXIN2+
Bias Current
IN1+, IN2+, RXIN1+, RXIN2+
Bias Current Matching
IN1-, IN2-, RXIN1-, RXIN2-
Bias Current
IN1-, IN2-, RXIN1-, RXIN2-
Bias Current Matching
Input Resistance
Input Capacitance
Z
OL
PSRR
V
OS
I
B+
I
OS+
I
B-
I
OS-
R
IN
C
IN
IN1+, IN2+, RXIN1+, RXIN2+
IN1-, IN2-, RXIN1-, RXIN2-
IN1+, IN2+, IN1-, IN2-, RXIN1+, RXIN2+,
RXIN1-, RXIN2-
-2V
≤
P
OUT
≤
+2V
V
CC
- V
EE
= ±4.75V to ±5.25V
V
LP
- V
LM
= ±2.25V to ±2.75V
50
50
300
87
100
±2
±1
±0.7
±2.6
±1.2
1.1
200
2
±20
±10
±20
kΩ
dB
mV
µA
µA
µA
µA
MΩ
Ω
pF
SYMBOL
V
OS(DRIFT)
R
OUT
BW
SR
P
N
V
OUT(DIFF)
= 14V
P-P
step
f = 100kHz to 1.1MHz, referred to 100Ω line
No sustained oscillations
-200mV
≤
V
OUT
≤
+200mV
SHDN = V
CC
6
CONDITIONS
MIN
TYP
±12
8
8
80
250
-127
1000
10
MAX
UNITS
µV/°C
Ω
MHz
V/µs
dBm/Hz
pF
Note 1:
All devices are 100% production tested at T
A
= +25°C. Specifications over temperature limits are guaranteed by design.
Note 2:
Guaranteed by the PSRR test.
Note 3:
Implied by worst-case output voltage swing (V
OUT(DIFF)
), crest factor (Cr), and load impedance (R
L
):
250
×
V
2 OUT(DIFF)
P
DRIVER
=
10 log
10
dBmW
2
Cr
×
R
L
Note 4:
Device may exceed absolute maximum ratings for power dissipation if unit is subjected to full-scale sinusoids for long
periods. See the
Applications Information
section.
Note 5:
Receiver specifications guaranteed for MAX9482 only.
4
_______________________________________________________________________________________
Low-Power, Low-Distortion, Central-Office
ADSL Drivers and Integrated Drivers/Receivers
Typical Operating Characteristics
(V
CC
= +5V, V
EE
= -5V, V
LP
= +2.5V, V
LM
= -2.5V, DGND = 0, RXIN1+ = RXIN2+ = 0, IN1+ = IN2+ = 0, R
L
= 16Ω is connected from
OUT1 to OUT2, SHDN = 0, T
A
= +25°C, unless otherwise noted. Preamp configured for A
V
= +1 with 1kΩ from RXOUT_- to RXIN_-.
Receiver configured for A
V
= +1 with 1kΩ from POUT_ to IN_-.)
SUPPLY CURRENT vs. OUTPUT VOLTAGE
=
±5V
SUPPLY
=
±2.5V
SUPPLY
INPUT = DC
MAX9480 toc01
MAX9480/MAX9481/MAX9482
SUPPLY CURRENT vs. TEMPERATURE
MAX9480 toc02
SHUTDOWN CURRENT vs. TEMPERATURE
MAX9481
SHUTDOWN CURRENT (mA)
2.4
2.5V SUPPLY
MAX9480 toc03
600
500
SUPPLY CURRENT (mA)
400
300
200
100
0
0
1
30
MAX9481
26
SUPPLY CURRENT (mA)
2.5V SUPPLY
5V SUPPLY
3.0
I
DC
f
INPUT
= 1MHz
I
AVG
I
AVG
22
1.8
18
1.2
5V SUPPLY
f
INPUT
= 100kHz
14
0.6
10
2
3
4
5
6
7
8
9
10
-40
-15
10
35
60
85
V
OUT
P-P
(V)
TEMPERATURE (°C)
0
-40
-15
10
35
60
85
TEMPERATURE (°C)
TRANSMIT PATH
FREQUENCY RESPONSE
80
60
40
GAIN (dB)
20
0
-20
-40
-60
-80
0.01
= GAIN
= PHASE
0.1
1
FREQUENCY (MHz)
10
OVERALL GAIN = -3V/V
PREAMP GAIN = +1V/V
OVERALL GAIN = -9V/V
PREAMP GAIN = +3V/V
MAX9480 toc04
DRIVER HARMONIC DISTORTION
vs. FREQUENCY
V
OUT
P-P
= 2.0V
-160
HARMONIC DISTORTION (dBc)
-20
-180
-200
-220
-240
-260
-280
-300
100
-100
0.01
0.1
1
10
FREQUENCY (MHz)
PHASE (DEGREES)
MAX9480 toc05
-140
0
-40
2ND HARMONIC
-60
-80
2ND HARMONIC
3RD
DRIVER HARMONIC DISTORTION
vs. OUTPUT VOLTAGE
-10
HARMONIC DISTORTION (dBc)
-20
-30
GAIN (dB)
-40
-50
-60
-70
-80
-90
-100
2
4
6
8
10
12
14
16
18
V
OUT
(DIFF) (V
P-P
)
SUPPLY CROSSOVER REGION
-30
-40
0.01
2ND HARMONIC
3RD
2ND HARMONIC
f = 1MHz
MAX9480 toc06
RECEIVER AMPLIFIER
FREQUENCY RESPONSE
30
20
10
0
-10
A
-20
= GAIN
= PHASE
0.1
1
10
100
C
0
B
C
-45
-90
-135
1000
A
B
90
45
PHASE (DEGREES)
MAX9480 toc07
0
135
FREQUENCY (MHz)
C: GAIN = 1V/V
A: GAIN = 10V/V
B: GAIN = 5V/V
_______________________________________________________________________________________
5
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
