0.8mm
3mm
LT1739
Dual 500mA, 200MHz
xDSL Line Driver Amplifier
FEATURES
DESCRIPTIO
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3mm 4mm High Power DFN Package The LT 1739 is a 500mA minimum output current, dual op
n
Exceeds All Requirements For Full Rate, amp with outstanding distortion performance. The ampli-
Downstream ADSL Line Drivers fiers are gain-of-ten stable, but can be easily compensated
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500mA Minimum I for lower gains. The extended output swing allows for
OUT
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11.1V Output Swing, V = 12V, R = 100W lower supply rails to reduce system power. Supply current
S L
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10.9V Output Swing, V = 12V, I = 250mA is set with an external resistor to optimize power dissipa-
S L
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Low Distortion: 82dBc at 1MHz, 2V Into 50W tion. The LT1739 features balanced, high impedance in-
P-P
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Power Saving Adjustable Supply Current puts with low input bias current and input offset voltage.
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Power Enhanced TSSOP-20 Small Footprint Package Active termination is easily implemented for further sys-
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200MHz Gain Bandwidth tem power reduction. Short-circuit protection and thermal
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600V/m s Slew Rate shutdown insure the devices ruggedness.
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Specified at 12V and 5V
The outputs drive a 100W load to 11.1V with 12V
U supplies, and 10.9V with a 250mA load. The LT1739 is a
APPLICATIO S
pin-for-pin replacement for the LT1794 in xDSL line driver
applications and requires no circuit changes.
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High Density ADSL Central Office Line Drivers
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The LT1739 is available in the very small, thermally
High Efficiency ADSL, HDSL2, G.lite,
enhanced, 3mm 4mm DFN package or a 20-lead TSSOP
SHDSL Line Drivers
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for maximum port density in central office line driver
Buffers
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applications. For a dual version of the LT1739, see the
Test Equipment Amplifiers
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LT6301 data sheet.
Cable Drivers
, LTC and LT are registered trademarks of Linear Technology Corporation.
TYPICAL APPLICATIO
High Efficiency 12V Supply ADSL Central Office Line Driver
12V
3mm 4mm DFN Package
R
BIAS
Bottom View
24.9k
+IN +
SHDN
12.7
1/2
LT1739 EXPOSED
THERMAL
PAD
1k
1:2*
110
100
1000pF
110
1739 TA01
1k
*COILCRAFT X8390-A OR EQUIVALENT
I = 10mA PER AMPLIFIER
SUPPLY
12.7
1/2
WITH R = 24.9k
BIAS
LT1739
SHDNREF
IN +
12V
1739fas, sn1739
1
4mm
1739 TA02
U
ULT1739
ABSOLUTE MAXIMUM RATINGS
(Note 1)
+
Supply Voltage (V to V ) ................................. 13.5V Junction Temperature
Input Current ..................................................... 10mA FE Package ....................................................... 150 C
Output Short-Circuit Duration (Note 2) ........... Indefinite UE Package ...................................................... 125 C
Operating Temperature Range ............... 40 C to 85 C Storage Temperature Range
Specified Temperature Range (Note 3) .. 40 C to 85 C FE Package ....................................... 65 C to 150 C
UE Package ...................................... 65 C to 125 C
Lead Temperature (Soldering, 10 sec).................. 300 C
PACKAGE/ORDER INFORMATION
TOP VIEW
ORDER PART ORDER PART
NUMBER NUMBER
V 1 20 V
TOP VIEW
NC 2 19 NC
LT1739CFE LT1739CUE
IN A 1 12 V
IN 3 18 OUT
LT1739IFE LT1739IUE
+
+IN A 2 11 OUT A
+IN 4 17 V
+
SHDN 3 10 V
SHDN 5 16 NC
+
SHDNREF 6 15 NC SHDNREF 4 9 V
+
+IN 7 14 V +IN B 5 8 OUT B
UE PART
IN 8 13 OUT
IN B 6 7 V
MARKING
NC 9 12 NC
UE12 PACKAGE
V 10 11 V
12-LEAD (4mm 3mm) PLASTIC DFN 1739
1739I
T = 125 C, q = 60 C/W, q = 3 C/W (Note 4)
JMAX JA JC
FE PACKAGE
20-LEAD PLASTIC TSSOP UNDERSIDE METAL CONNECTED TO V
T = 150 C, q = 40 C/W, q = 3 C/W (Note 4)
JMAX JA JC
UNDERSIDE METAL CONNECTED TO V
Consult LTC Marketing for parts specified with wider operating temperature ranges.
ELECTRICAL CHARACTERISTICS
The l denotes the specifications which apply over the full specified temperature range, otherwise specifications are at T = 25 C.
A
+
V = 0V, pulse tested, 5V V 12V, V = 0V, R = 24.9k between V and SHDN unless otherwise noted. (Note 3)
CM S SHDNREF BIAS
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
V Input Offset Voltage 15.0 mV
OS
l 7.5 mV
Input Offset Voltage Matching 0.3 5.0 mV
l 7.5 mV
Input Offset Voltage Drift l 10 m V/ C
I Input Offset Current 100 500 nA
OS
l 800 nA
I Input Bias Current 0.1 4 m A
B
l 6 m A
Input Bias Current Matching 100 500 nA
l 800 nA
e Input Noise Voltage Density f = 10kHz 8 nV/ Hz
n
i Input Noise Current Density f = 10kHz 0.8 pA/ Hz
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1739fas, sn1739
2
U W U
U WWW