FEATURES
n
n
n
n
n
n
n
LT1719
4.5ns Single/Dual Supply
3V/5V Comparator with
Rail-to-Rail Output
DESCRIPTION
The LT
®
1719 is an UltraFast™ comparator optimized for low
voltage operation. The input voltage range extends from
100mV below V
EE
to 1.2V below V
CC
. Internal hysteresis
makes the LT1719 easy to use even with slow moving input
signals. The rail-to-rail outputs directly interface to TTL
and CMOS. Alternatively the symmetric output drive can be
harnessed for analog applications or for easy translation to
other single supply logic levels. A shutdown control allows
for reduced power consumption and extended battery life
in portable applications.
The LT1719 is available in the SO-8 and 6-lead SOT-23
package. The SO-8 package has separate supplies which
allow flexible operation, accomodating separate analog
input ranges and output logic levels.
For a dual/quad comparator with similar performance, see
the LT1720/LT1721.
L,
LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. UltraFast is a trademark of Linear Technology Corporation. All other
trademarks are the property of their respective owners.
UltraFast: 4.5ns at 20mV Overdrive
7ns at 5mV Overdrive
Low Power: 4.2mA at 3V
Separate Input and Output Power Supplies
(SO-8 Only)
Output Optimized for 3V and 5V Supplies
TTL/CMOS Compatible Rail-to-Rail Output
Low Power Shutdown Mode: 0.1μA
Low Profile (1mm) SOT-23 (ThinSOT™) Package
APPLICATIONS
n
n
n
n
n
n
n
High Speed Differential Line Receiver
Crystal Oscillator Circuits
Level Translators
Threshold Detectors/Discriminators
Zero-Crossing Detectors
High Speed Sampling Circuits
Delay Lines
TYPICAL APPLICATION
2.7V to 6V Crystal Oscillator with TTL/CMOS Output
2.7V TO 6V
2k
220Ω
6
5
4
3
2
FALLING EDGE
(t
PDHL
)
8
Propagation Delay vs Overdrive
25°C
V
STEP
= 100mV
V
+
= 5V
C
LOAD
= 10pF
1MHz TO 10MHz
CRYSTAL (AT-CUT)
7
RISING EDGE
(t
PDLH
)
+
–
GROUND
CASE
OUTPUT
C1
LT1719
2k
1719 TA01
DELAY (ns)
620Ω
1
0
0
10
30
OVERDRIVE (mV)
20
40
50
1719 TA02
0.1μF
1.8k
1719fa
1
LT1719
ABSOLUTE MAXIMUM RATINGS
(Note 1)
Supply Voltage
+ V
S
to GND (LT1719S8) ........................................ 7V
V
CC
to V
EE
(LT1719S8) ........................................ 12V
+V
S
to V
EE
(LT1719S8) ....................................... 12V
V
EE
to GND (LT1719S8) ....................... –12V to 0.3V
V
+
to V
–
(LT1719S6) ...............................................7V
Input Current (+IN, –IN or SHDN) ...................... ±10mA
Output Current (Continuous) ........................... ± 20mA
Operating Temperature Range
C-Grade .................................................. 0°C to 70°C
I-Grade ............................................... –40°C to 85°C
Junction Temperature ......................................... 150°C
Storage Temperature Range.................. –65°C to 150°C
Lead Temperature (Soldering, 10 sec) ................. 300°C
PIN CONFIGURATION
TOP VIEW
V
CC
1
+IN 2
–IN 3
V
EE
4
+
–
8
7
6
5
+V
S
OUT
SHDN
GND
–IN 1
V
–
2
TOP VIEW
6 SHDN
5 OUT
4 V
+
+IN 3
S8 PACKAGE
8-LEAD PLASTIC SO
T
JMAX
= 150°C,
θ
JA
= 110°C/W
S6 PACKAGE
6-LEAD PLASTIC TSOT-23
T
JMAX
= 150°C,
θ
JA
= 230°C/W
ORDER INFORMATION
LEAD FREE FINISH
LT1719CS8#PBF
LT1719IS8#PBF
LT1719CS6#PBF
LT1719IS6#PBF
TAPE AND REEL
LT1719CS8#TRPBF
LT1719IS8#TRPBF
LT1719CS6#TRPBF
LT1719IS6#TRPBF
PART MARKING
1719
1719I
LTHW
LTJF
PACKAGE DESCRIPTION
8-Lead Plastic SO
8-Lead Plastic SO
6-Lead Plastic TSOT-23
6-Lead Plastic TSOT-23
TEMPERATURE RANGE
0°C to 70°C
–40°C to 85°C
0°C to 70°C
–40°C to 85°C
Consult LTC Marketing for parts specified with wider operating temperature ranges.
Consult LTC Marketing for information on non-standard lead based finish parts.
For more information on lead free part marking, go to:
http://www.linear.com/leadfree/
For more information on tape and reel specifications, go to:
http://www.linear.com/tapeandreel/
1719fa
2
LT1719
ELECTRICAL CHARACTERISTICS
SYMBOL PARAMETER
V
CC
– V
EE
Input Supply Voltage
+ V
S
V
+
– V
–
V
CMR
V
TRIP+
V
TRIP–
V
OS
V
HYST
ΔV
OS
/ΔT
I
B
I
OS
CMRR
PSRR
A
V
V
OH
V
OL
t
PD20
Output Supply Voltage
Supply Voltage
Input Voltage Range
Input Trip Points
Input Offset Voltage
Input Hysteresis Voltage
Input Offset Voltage Drift
Input Bias Current
Input Offset Current
Common Mode Rejection Ratio
Power Supply Rejection Ratio
Voltage Gain
Output High Voltage
Output Low Voltage
Propagation Delay
(Note 4)
(Note 5)
(Note 6)
(Note 7)
(Note 8)
I
SOURCE
= 4mA, V
IN
= V
TRIP+
+ 10mV
I
SINK
= 10mA, V
IN
= V
TRIP–
– 10mV
V
OVERDRIVE
= 20mV (Note 9) V
EE
= 0V(LT1719S8)
V
–
= 0V(LT1719S6)
V
OVERDRIVE
= 20mV, V
EE
= –5V
t
PD5
t
SKEW
t
r
t
f
t
JITTER
f
MAX
t
OFF
t
ON
I
CC
I
EE
Propagation Delay
Propagation Delay Skew
Output Rise Time
Output Fall Time
Output Timing Jitter
Maximum Toggle Frequency
Turn-Off Delay
Wake-Up Delay
Positive Input Stage Supply Current
Negative Input Stage Supply Current
(LT1719S8 Only)
l
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
CM
= 1V, V
SHDN
= 0.5V, V
OVERDRIVE
= 20mV, C
OUT
= 10pF and for the
LT1719S8 V
CC
= +V
S
= 5V and V
EE
= –5V, for the LT1719S6 V
+
= 5V, V
–
= 0V, unless otherwise specified.
CONDITIONS
(LT1719S8 Only)
(LT1719S8 Only)
(LT1719CS6 Only)
(Note 2)
(Note 3)
(Note 3)
(Note 3)
(LT1719S8)
(LT1719S6)
l
l
l
l
l
l
l
l
l
l
l
l
MIN
2.7
2.7
2.7
V
EE
– 0.1
V
–
– 0.1
–1.5
–5.5
TYP
MAX
10.5
6
6
V
CC
– 1.2
V
+
– 1.2
5.5
1.5
UNITS
V
V
V
V
V
mV
mV
mV
mV
mV
μV/°C
μA
μA
dB
dB
dB
dB
V
V
0.4
2.0
–6
55
55
65
65
3.5
10
–2.5
0.2
70
65
80
80
∞
2.5
3.5
7
0
0.6
(LT1719S8)
(LT1719S6)
(LT1719S8)
(LT1719S6)
(LT1719S8)
(LT1719S6)
l
l
l
l
l
l
+V
S
– 0.4
V
+
– 0.4
0.4
4.5
4.2
7
0.5
2.5
2.2
10
13
1.5
6.5
8.0
V
ns
ns
ns
ns
ns
ns
ns
ns
ps
RMS
ps
RMS
MHz
MHz
ns
ns
V
OVERDRIVE
= 5mV (Notes 9, 10) V
EE
= 0V(LT1719S8)
V
–
= 0V(LT1719S6)
(Note 11)
10% to 90%
90% to 10%
V
IN
= 1.2V
P-P
(6dBm), Z
IN
= 50Ω
f = 20MHz
V
OVERDRIVE
= 50mV, +V
S
or V
+
= 3V
V
OVERDRIVE
= 50mV, +V
S
or V
+
= 5V
Time to Z
OUT
≥10kΩ
Time to V
OH
or V
OL
, I
LOAD
= 1mA
+ V
S
= V
CC
= 5V, V
EE
= –5V
+ V
S
= V
CC
= 5V, V
EE
= –5V
t
PD+
t
PD–
15
11
70
62.5
75
350
l
l
l
l
1
0.9
–4.8
–3.8
–2.6
–2.2
2.2
1.8
mA
mA
mA
mA
(LT1719S8 Only) + V
S
= V
CC
= 3V, V
EE
= 0V
(LT1719S8 Only) + V
S
= V
CC
= 3V, V
EE
= 0V
1719fa
3
LT1719
ELECTRICAL CHARACTERISTICS
SYMBOL PARAMETER
I
S
I
+
I
SHDN5
I
SHDN3
I
CCS
I
SS
I
EES
I
+S
I
CCSO
I
SSO
I
EEO
I
+O
Positive Output Stage Supply Current
Supply Current
Shutdown Pin Current
Shutdown Pin Current
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
CM
= 1V, V
SHDN
= 0.5V, V
OVERDRIVE
= 20mV, C
OUT
= 10pF and for the
LT1719S8 V
CC
= +V
S
= 5V and V
EE
= –5V, for the LT1719S6 V
+
= 5V, V
–
= 0V, unless otherwise specified.
CONDITIONS
+ V
S
= V
CC
= 5V, V
EE
= –5V
l
l
l
l
l
l
l
l
l
l
l
l
l
l
MIN
TYP
4.2
3.3
4.6
4.2
MAX
8
6
9
7
–30
–20
30
50
80
20
20
40
UNITS
mA
mA
mA
mA
μA
μA
μA
μA
μA
μA
μA
μA
μA
μA
(LT1719S8 Only) V
S
= V
CC
= 3V, V
EE
= 0V
(LT1719S6) V
+
= 5V
V
+
= 3V
+V
S
or V
+
= 5V
+V
S
or V
+
= 3V
–300
–200
–110
–80
0.2
7
–0.2
7
0.1
0.1
0.1
0.2
Disabled Supply Currents (LT1719S8) + V
S
= 6V, V
CC
= 5V, V
EE
= –5V
(LT1719S8) V
SHDN
= +V
S
– 0.5V
(LT1719S8)
(LT1719S6) V
+
= 6V, V
SHDN
= +V
S
– 0.5V
(LT1719S8) + V
S
= 6V, V
CC
= 5V, V
EE
= –5V
(LT1719S8) Shutdown Pin Open
(LT1719S8)
(LT1719S6) V
+
= 6V, Shutdown Pin Open
–30
–20
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2:
If one input is within these common mode limits, the other input
can go outside the common mode limits and the output will be valid.
Note 3:
The LT1719 comparator includes internal hysteresis. The trip
points are the input voltage needed to change the output state in each
direction. The offset voltage is defined as the average of V
TRIP+
and V
TRIP–
,
while the hysteresis voltage is the difference of these two.
Note 4:
The LT1719S8 common mode rejection ratio is measured with
V
CC
= 5V, V
EE
= – 5V and is defined as the change in offset voltage measured
from V
CM
= –5.1V to V
CM
= 3.8V, divided by 8.9V.
Note 5:
The LT1719S6 common mode rejection ratio is measured with
V
+
= 5V and is defined as the change in offset voltage measured from
V
CM
= –0.1V to V
CM
= 3.8V, divided by 3.9V.
Note 6:
The LT1719S8 power supply rejection ratio is measured with
V
CM
= 1V and is defined as the worst of: the change in offset voltage from
V
EE
= – 5.5V to V
EE
= 0V divided by 5.5V, or the change in offset voltage
from V
CC
= +V
S
= 2.7V to V
CC
= +V
S
= 6V (with V
EE
= 0V) divided by 3.3V.
Note 7:
The LT1719S6 power supply rejection ratio is measured with
V
CM
= 1V and is defined as the change in offset voltage measured from
V
+
= 2.7V to V
+
= 6V, divided by 3.3V.
Note 8:
Because of internal hysteresis, there is no small-signal region in
which to measure gain. Proper operation of internal circuity is ensured by
measuring V
OH
and V
OL
with only 10mV of overdrive.
Note 9:
Propagation delay measurements made with 100mV steps.
Overdrive is measured relative to V
TRIP±
.
Note 10:
t
PD
cannot be measured in automatic handling equipment with
low values of overdrive. The LT1719 is 100% tested with a 100mV step
and 20mV overdrive. Correlation tests have shown that t
PD
limits can be
guaranteed with this test, if additional DC tests are performed to guarantee
that all internal bias conditions are correct.
Note 11:
Propagation Delay Skew is defined as:
t
SKEW
= |t
PDLH
– t
PDHL
|
1719fa
4
LT1719
TYPICAL PERFORMANCE CHARACTERISTICS
Input Offset and Trip Voltages
vs Supply Voltage
3
V
OS
AND TRIP POINT VOLTAGE (mV)
Input Offset and Trip Voltages
vs Temperature
3
COMMON MODE INPUT VOLTAGE (V)
Input Common Mode Limits
vs Temperature
4.2
+V
S
= V
CC
OR V
+
= 5V
4.0
3.8
0
–0.2
–5.0
–5.2
–5.4
–50 –25
V
EE
= –5V (LT1719S8)
50
25
75
0
TEMPERATURE (°C)
100
125
V
–
= GND (LT1719S6)
V
OS
AND TRIP POINT VOLTAGE (mV)
V
TRIP+
2
1
V
OS
0
–1
–2
25°C
V
CM
= 1V
V
EE
OR V
–
= GND
5.5 6.0
3.0
3.5 4.0 4.5 5.0
SUPPLY VOLTAGE, V
CC
= +V
S
OR V
+
(V)
1719 G01
2
1
V
TRIP
+
V
OS
0
–1
–2
V
TRIP–
V
TRIP–
+V
S
= V
CC
or V
+
= 5V
V
CM
= 1V
V
EE
OR V
–
= GND
–3
2.5
–3
–60 –40 –20 0 20 40 60 80 100 120 140
TEMPERATURE (°C)
1719 G02
1719 G03
Input Current
vs Differential Input Voltage
2
25°C
1
SUPPLY CURRENT (mA)
Quiescent Supply Current
vs Temperature
10
V
CC
= +V
S
OR V
+
= 5V
8 V
EE
= GND
6
4
2
0
–2
–4
–6
–50
–25
0
25
50
I
EE
(LT1719S8)
75
100
125
I
CC
(LT1719S8)
+I
S
(LT1719S8)
Quiescent Supply Current
vs Supply Voltage
6
5
T
A
= 25°C
V
EE
= GND
I
+
(LT1719S6)
I
+
(LT1719S6)
SUPPLY CURRENTS (mA)
0
4
3
2
1
0
–1
–2
–3
0
1
3
4
5
6
2
+
SUPPLY VOLTAGE, V
CC
= +V
S
OR V (V)
7
I
EE
(LT1719S8)
I
CC
(LT1719S8)
I
S
(LT1719S8)
INPUT BIAS (μA)
–1
–2
–3
–4
–5
–6
–7
–5 –4 –3 –2 –1 0 1 2 3 4
DIFFERENTIAL INPUT VOLTAGE (V)
5
TEMPERATURE (°C)
1339 G05
1719 G04
1719 G06
Propagation Delay
vs Load Capacitance
9
8
Propagation Delay
vs Temperature
8.0
RISING EDGE
(t
PDLH
)
PROPAGATION DELAY (ns)
Propagation Delay
vs Supply Voltage
5.5
25°C
V
STEP
= 100mV
OVERDRIVE = 20mV
C
LOAD
= 10pF
V
EE
/V
–
= GND
7
6
5
4
3
2
1
0
0
7.0
6.5
6.0
5.5
5.0
4.5
PROPAGATION DELAY (ns)
PROPAGATION DELAY (ns)
25°C
V
STEP
= 100mV
OVERDRIVE = 20mV
+V
S
= V
CC
OR V
+
= 5V
V
EE
OR V
–
= 0V
7.5
t
PDLH
V
CM
= 1V
V
STEP
= 100mV
C
LOAD
= 10pF
V
EE
OR V
–
= GND
+V
S
= V
CC
= V
+
3V
5V
5.0
t
TPLH
t
TPHL
FALLING EDGE
(t
PDHL
)
OVERDRIVE = 5mV
OVERDRIVE = 20mV
3V
5V
4.5
t
TPLH
4.0
t
TPHL
V
EE
= –5V
(V
CC
, +V
S
= 5.5V
MAX
)
(LT1719S8 ONLY)
3.5
2.5
5.5 6.0
3.0
3.5 4.0 4.5 5.0
SUPPLY VOLTAGE, +V
S
= V
CC
OR V
+
(V)
1719 G09
40
30
OUTPUT LOAD CAPACITANCE (pF)
10
20
50
1719 G07
4.0
–50 –25
0
50
75
25
TEMPERATURE (°C)
100
125
1719 G08
1719fa
5