LT1711/LT1712
Single/Dual 4.5ns, 3V/5V/ 5V,
Rail-to-Rail Comparators
FEATURES
DESCRIPTIO
TM
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Ultrafast: 4.5ns at 20mV Overdrive The LT 1711/LT1712 are UltraFast 4.5ns comparators
5.5ns at 5mV Overdrive featuring rail-to-rail inputs, rail-to-rail complementary out-
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Rail-to-Rail Inputs puts and an output latch. Optimized for 3V and 5V power
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Rail-to-Rail Complementary Outputs (TTL/CMOS supplies, they operate over a single supply voltage range
Compatible) from 2.4V to 12V or from 2.4V to 6V dual supplies.
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Specified at 2.7V, 5V and 5V Supplies
The LT1711/LT1712 are designed for ease of use in a
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Output Latch
variety of systems. In addition to wide supply voltage
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Inputs Can Exceed Supplies Without Phase Reversal
flexibility, rail-to-rail input common mode range extends
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LT1711: 8-Lead MSOP Package
100mV beyond both supply rails, and the outputs are
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LT1712: 16-Lead Narrow SSOP Package
protected against phase reversal for inputs extending
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further beyond the rails. Also, the rail-to-rail inputs may be
APPLICATIO S
taken to opposite rails with no significant increase in input
current. The rail-to-rail matched complementary outputs
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High Speed Automatic Test Equipment
interface directly to TTL or CMOS logic and can sink 10mA
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Current Sense for Switching Regulators
+
to within 0.5V of GND or source 10mA to within 0.7V of V .
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Crystal Oscillator Circuits
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High Speed Sampling Circuits
The LT1711/LT1712 have internal TTL/CMOS compatible
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High Speed A/D Converters
latches for retaining data at the outputs. Each latch holds
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Pulse Width Modulators
data as long as the latch pin is held high. Latch pin
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Window Comparators
hysteresis provides protection against slow moving or
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Extended Range V/F Converters
noisy latch signals. The LT1711 is available in the 8-pin
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Fast Pulse Height/Width Discriminators
MSOP package. The LT1712 is available in the 16-pin
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Line Receivers
narrow SSOP package.
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High Speed Triggers
, LTC and LT are registered trademarks of Linear Technology Corporation.
UltraFast is a trademark of Linear Technology Corporation.
TYPICAL APPLICATIO
A 4 NTSC Subcarrier Voltage-Tunable Crystal Oscillator
5V
LT1711/LT1712 Propagation Delay
47k* vs Input Overdrive
LT1004-2.5
1N4148
3.9k*
V
IN
0V TO 5V 6.0
T = 25C
1M A
1M* 1k*
+
V = 5V
5.5
V = 0V
MV-209
5V
V = 100mV
STEP
VARACTOR
1M
0.047F
DIODE
1M C SELECT 5.0
2k
+
(CHOOSE FOR CORRECT t
PD
100pF
PLL LOOP RESPONSE)
4.5
390W
Y1** 15pF 100pF t
PD
4.0
+
LT1711
3.5
FREQUENCY
OUTPUT
171112 TA01
2k 3.0
0 10 20 40 50 60
30
200pF INPUT OVERDRIVE (mV)
* 1% FILM RESISTOR
171112 TA02
** NORTHERN ENGINEERING LABS C-2350N-14.31818MHz
1
PROPAGATION DELAY (ns)
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ULT1711/LT1712
ABSOLUTE AXI U RATI GS (Note 1)
Supply Voltage Output Current (Continuous) .............................. 20mA
+
V to V ............................................................ 12.6V Operating Temperature Range ................ 40 C to 85 C
+
V to GND ........................................................ 12.6V Specified Temperature Range (Note 2) ... 40 C to 85 C
V to GND .............................................10V to 0.3V Junction Temperature.......................................... 150 C
Differential Input Voltage ................................... 12.6V Storage Temperature Range ................. 65 C to 150 C
Latch Pin Voltage...................................................... 7V Lead Temperature (Soldering, 10 sec).................. 300 C
Input and Latch Current ..................................... 10mA
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PACKAGE/ORDER I FOR ATIO
TOP VIEW
ORDER PART ORDER PART
LATCH
NUMBER NUMBER
IN A 1 16
ENABLE A
+IN A 2 15 GND
TOP VIEW
LT1711CMS8 LT1712CGN
V 3 14 Q A
+
V 1 8 Q
LT1711IMS8 LT1712IGN
+
V 4 13 Q A
7 Q
+IN 2
+
IN 3 6 GND
V 5 12 Q B
5 LATCH
V 4
V 6 11 Q B
ENABLE
MS8 PACKAGE
MS8 PART MARKING GN PART MARKING
+IN B 7 10 GND
8-LEAD PLASTIC MSOP
LATCH
IN B 8 9
T = 150 C, q = 250 C/ W (NOTE 12)
ENABLE B
JMAX JA LTTC 1712
GN PACKAGE
LTTD 1712I
16-LEAD PLASTIC SSOP
T = 150 C, q = 120 C/ W (NOTE 12)
JMAX JA
Consult factory for parts specified with wider operating temperature ranges.
ELECTRICAL CHARACTERISTICS
The l denotes specifications which apply over the full operating temperature range, otherwise specifications are at T = 25 C.
A
+ + +
V = 2.7V or V = 5V, V = 0V, V = V /2, V = 0.8V, C = 10pF, V = 20mV, unless otherwise specified.
CM LATCH LOAD OVERDRIVE
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
+
V Positive Supply Voltage Range l 2.4 7 V
+
V Input Offset Voltage (Note 4) R = 50W , V = V /2 0.5 5.0 mV
OS S CM
+
R = 50W , V = V /2 l 6.0 mV
S CM
R = 50W , V = 0V 0.7 mV
S CM
+
R = 50W , V = V 1mV
S CM
D V /D T Input Offset Voltage Drift l 10 m V/ C
OS
I Input Offset Current 0.2 3 m A
OS
l 6 m A
I Input Bias Current (Note 5) 18 5 5 m A
B
l 35 10 m A
+
V Input Voltage Range (Note 9) l 0.1 V + 0.1 V
CM
+
CMRR Common Mode Rejection Ratio V = 5V, 0V V 5V 56 65 dB
CM
+
V = 5V, 0V V 5V l 53 dB
CM
+
V = 2.7V, 0V V 2.7V 54 65 dB
CM
+
V = 2.7V, 0V V 2.7V l 50 dB
CM
+ +
PSRR Positive Power Supply Rejection Ratio 2.4V V 7V, V = 0V 58 75 dB
CM
l 56 dB
2
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