LT1739_15 Datasheet, PDF (1/20 Pages) Linear Technology – Dual 500mA, 200MHz xDSL Line Driver Amplifier

FEATURES
s _{3mm × 4mm High Power DFN Package}
s _{Exceeds All Requirements For Full Rate,}
Downstream ADSL Line Drivers
s _{±500mA Minimum IOUT}
s _{±11.1V Output Swing, VS = ±12V, RL = 100Ω}
s _{±10.9V Output Swing, VS = ±12V, IL = 250mA}
s _{Low Distortion: – 82dBc at 1MHz, 2VP-P Into 50Ω}
s _{Power Saving Adjustable Supply Current}
s _{Power Enhanced TSSOP-20 Small Footprint Package}
s _{200MHz Gain Bandwidth}
s _{600V/µs Slew Rate}
s _{Specified at ±12V and ±5V}
U
APPLICATIO S
s _{High Density ADSL Central Office Line Drivers}
s _{High Efficiency ADSL, HDSL2, G.lite,}
SHDSL Line Drivers
s _Buffers
s _{Test Equipment Amplifiers}
s _{Cable Drivers}
LT1739
Dual 500mA, 200MHz
xDSL Line Driver Amplifier
DESCRIPTIO
The LT^®1739 is a 500mA minimum output current, dual op
amp with outstanding distortion performance. The ampli-
fiers are gain-of-ten stable, but can be easily compensated
for lower gains. The extended output swing allows for
lower supply rails to reduce system power. Supply current
is set with an external resistor to optimize power dissipa-
tion. The LT1739 features balanced, high impedance in-
puts with low input bias current and input offset voltage.
Active termination is easily implemented for further sys-
tem power reduction. Short-circuit protection and thermal
shutdown insure the device’s ruggedness.
The outputs drive a 100Ω load to ±11.1V with ±12V
supplies, and ±10.9V with a 250mA load. The LT1739 is a
pin-for-pin replacement for the LT1794 in xDSL line driver
applications and requires no circuit changes.
The LT1739 is available in the very small, thermally
enhanced, 3mm × 4mm DFN package or a 20-lead TSSOP
for maximum port density in central office line driver
applications. For a dual version of the LT1739, see the
LT6301 data sheet.
, LTC and LT are registered trademarks of Linear Technology Corporation.
TYPICAL APPLICATIO
High Efficiency ±12V Supply ADSL Central Office Line Driver
12V
+IN
1000pF
110Ω
110Ω
+
1/2
LT1739
–
1k
R_BIAS
24.9k
SHDN
12.7Ω
1:2*
1k
100Ω
1739 TA01
–
1/2
LT1739
12.7Ω
*COILCRAFT X8390-A OR EQUIVALENT
I_SUPPLY = 10mA PER AMPLIFIER
WITH R_BIAS = 24.9k
–IN
+
SHDNREF
–12V
3mm × 4mm DFN Package
Bottom View
EXPOSED
THERMAL
PAD
0.8mm
3mm
4mm
1739 ^TA02
1739fas, sn1739
1