LT1711/LT1712
Single/Dual 4.5ns, 3V/5V/±5V,
Rail-to-Rail Comparators
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FEATURES
DESCRIPTIO
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Ultrafast: 4.5ns at 20mV Overdrive
The LT®1711/LT1712 are UltraFastTM 4.5ns comparators
featuringrail-to-railinputs,rail-to-railcomplementaryout-
puts and an output latch. Optimized for 3V and 5V power
supplies, they operate over a single supply voltage range
from 2.4V to 12V or from ±2.4V to ±6V dual supplies.
5.5ns at 5mV Overdrive
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Rail-to-Rail Inputs
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Rail-to-Rail Complementary Outputs (TTL/CMOS
Compatible)
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Specified at 2.7V, 5V and ±5V Supplies
The LT1711/LT1712 are designed for ease of use in a
variety of systems. In addition to wide supply voltage
flexibility, rail-to-rail input common mode range extends
100mV beyond both supply rails, and the outputs are
protected against phase reversal for inputs extending
furtherbeyondtherails. Also, therail-to-railinputsmaybe
taken to opposite rails with no significant increase in input
current. The rail-to-rail matched complementary outputs
interface directly to TTL or CMOS logic and can sink 10mA
towithin0.5VofGNDorsource10mAtowithin0.7VofV+.
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Output Latch
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Inputs Can Exceed Supplies Without Phase Reversal
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LT1711: 8-Lead MSOP Package
LT1712: 16-Lead Narrow SSOP Package
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APPLICATIO S
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High Speed Automatic Test Equipment
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Current Sense for Switching Regulators
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Crystal Oscillator Circuits
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High Speed Sampling Circuits
The LT1711/LT1712 have internal TTL/CMOS compatible
latches for retaining data at the outputs. Each latch holds
data as long as the latch pin is held high. Latch pin
hysteresis provides protection against slow moving or
noisy latch signals. The LT1711 is available in the 8-pin
MSOP package. The LT1712 is available in the 16-pin
narrow SSOP package.
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High Speed A/D Converters
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Pulse Width Modulators
Window Comparators
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Extended Range V/F Converters
Fast Pulse Height/Width Discriminators
Line Receivers
High Speed Triggers
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, LTC and LT are registered trademarks of Linear Technology Corporation.
UltraFast is a trademark of Linear Technology Corporation.
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TYPICAL APPLICATIO
A 4× NTSC Subcarrier Voltage-Tunable Crystal Oscillator
5V
LT1711/LT1712 Propagation Delay
vs Input Overdrive
47k* LT1004-2.5
1N4148
3.9k*
V
IN
0V TO 5V
6.0
T
= 25°C
= 5V
1M
A
1M*
1k*
+
V
V
V
–
5.5
= 0V
MV-209
VARACTOR
DIODE
5V
= 100mV
STEP
1M
0.047µF
C SELECT
5.0
4.5
4.0
3.5
3.0
1M
2k
+
(CHOOSE FOR CORRECT
PLL LOOP RESPONSE)
t
PD
100pF
–
390Ω
Y1** 15pF 100pF
t
PD
+
LT1711
FREQUENCY
OUTPUT
–
171112 TA01
2k
0
10
20
40
50
60
30
INPUT OVERDRIVE (mV)
200pF
* 1% FILM RESISTOR
** NORTHERN ENGINEERING LABS C-2350N-14.31818MHz
171112 TA02
1