1
LTC1443/LTC1444/LTC1445
Ultralow Power Quad
Comparators with Reference
s
Ultralow Quiescent Current: 8.5
A Max
s
Wide Supply Range
Single: 2V to 11V
Dual:
1V to
5.5V
s
Input Voltage Range Includes the Negative Supply
s
Reference Output Drives 0.01
F Capacitor
s
Adjustable Hysteresis (LTC1444/LTC1445)
s
TTL/CMOS Compatible Outputs
s
Propagation Delay: 12
s (Typ) (10mV Overdrive)
s
No Crowbar Current
s
40mA Continuous Source Current
s
Pin Compatible Upgrades for MAX924 (LTC1443)
The LTC
1443/LTC1444/LTC1445 are ultralow power quad
comparators with a built-in reference. The comparators
feature less than 8.5
A supply current over temperature,
an internal reference (1.182V
1% for LTC1443 or 1.221V
1% for LTC1444/LTC1445), programmable hysteresis
(LTC1444/LTC1445) and TTL/CMOS output (LTC1443/
LTC1445) that sinks and sources current (open-drain
output for LTC1444). The reference output can drive a
bypass capacitor of up to 0.01
F without oscillation.
The comparators operate from a single 2V to 11V supply
or a dual
1V to
5.5V supply (LTC1443). Comparator
hysteresis is easily programmable using two resistors and
the HYST pin (LTC1444/LTC1445). Each comparator's
input operates from the negative supply to within 1.3V of
the positive supply. The LTC1443/LTC1445 comparator
output stage can continuously source up to 40mA. By
eliminating the cross-conducting current that normally
happens when the comparator changes logic states, power
supply glitches are eliminated.
The LTC1443/LTC1444/LTC1445 are available in the
16-pin SO and PDIP packages.
, LTC and LT are registered trademarks of Linear Technology Corporation.
s
Battery-Powered System Monitoring
s
Threshold Detectors
s
Window Comparators
s
Oscillator Circuits
Reference Settling Test Circuit
+
IN A
+
5
OUT
V
+
V
R1
10k
R3
430
R2
2.4M
C1
1.0
F
IN A
HYST
REF
4
14
8
5V
TO 8V
LTC1443/44/45 TA01
LTC1445
3
9
2
1.21M
1%
3.4M
1%
V
IN
Reference Settling
8V
5V
V
REF
OUT
V
+
2ms/DIV
LTC1443/1444/1445 TA02
2mV/DIV
FEATURES
DESCRIPTIO
U
APPLICATIO S
U
TYPICAL APPLICATIO
U
2
LTC1443/LTC1444/LTC1445
Voltage:
V
+
to V
, V
+
to GND, GND to V
...........12V to 0.3V
IN
+
, IN
, HYST ................. (V
+
+ 0.3V) to (V
0.3V)
REF .................................. (V
+
+ 0.3V) to (V
0.3V)
OUT (LTC1443) ............. (V
+
+ 0.3V) to (GND 0.3V)
OUT (LTC1444/LTC1445)
......................................... (V
+
+ 0.3V) to (V
0.3V)
Storage Temperature Range ................. 65
C to 150
C
Lead Temperature Range (Soldering, 10 sec)....... 300
C
Current:
IN
+
, IN
, HYST .................................................. 20mA
REF ................................................................... 20mA
OUT .................................................................. 50mA
OUT Short Circuit Duration (V
+
5.5V) ....... Continuous
Power Dissipation .............................................. 500mW
Operating Temperature Range
Commercial ............................................ 0
C to 70
C
Industrial ............................................ 40
C to 85
C
ORDER PART
NUMBER
ORDER PART
NUMBER
LTC1443CN
LTC1443CS
LTC1443IN
LTC1443IS
LTC1444CN
LTC1444CS
LTC1444IN
LTC1444IS
LTC1445CN
LTC1445CS
LTC1445IN
LTC1445IS
T
JMAX
= 150
C,
JA
= 90
C/ W (N)
T
JMAX
= 150
C,
JA
= 150
C/ W (S)
Consult factory for Military grade parts.
1
2
3
4
5
6
7
8
TOP VIEW
S PACKAGE
16-LEAD PLASTIC SO
N PACKAGE
16-LEAD PDIP
16
15
14
13
12
11
10
9
OUT B
OUT A
V
+
IN A
IN A
+
IN B
IN B
+
REF
OUT C
OUT D
GND
IN D
+
IN D
IN C
+
IN C
V
1
2
3
4
5
6
7
8
TOP VIEW
16
15
14
13
12
11
10
9
OUT B
OUT A
V
+
IN A
IN A
+
IN B
IN B
+
REF
OUT C
OUT D
HYST
IN D
+
IN D
IN C
+
IN C
V
S PACKAGE
16-LEAD PLASTIC SO
N PACKAGE
16-LEAD PDIP
The
q
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25
C. V
+
= 5V, V
= GND = 0V, unless otherwise noted.
SYMBOL PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
Power Supply
V
+
Supply Voltage Range
q
2.0
11.0
V
I
CC
Supply Current
IN
+
= IN
= 80mV
q
5.5
8.5
A
HYST = REF (LTC1444/LTC1445)
Comparator
V
OS
Comparator Input Offset Voltage
V
CM
= 2.5V
q
3.0
10.0
mV
I
IN
Input Leakage Current (IN
+
, IN
)
V
IN
+
= V
IN
= 2.5V
q
0.01
1.0
nA
Input Leakage Current (HYST)
LTC1444/LTC1445
q
0.02
1.0
nA
V
CM
Comparator Input Common Mode Range
q
V
V
+
1.3V
V
CMRR
Common Mode Rejection Ratio
V
to (V
+
1.3V)
0.1
1.0
mV/V
PSRR
Power Supply Rejection Ratio
V
+
= 2V to 11V
0.1
1.0
mV/V
Noise
Voltage Noise
100Hz to 100kHz
20
V
RMS
V
HYST
Hysteresis Input Voltage Range
LTC1444, LTC1445
q
REF 50mV
REF
V
(Note 1)
T
JMAX
= 150
C,
JA
= 90
C/ W (N)
T
JMAX
= 150
C,
JA
= 150
C/ W (S)
ABSOLUTE AXI U RATI GS
W
W
W
U
PACKAGE/ORDER I FOR ATIO
U
U
W
ELECTRICAL CHARACTERISTICS
3
LTC1443/LTC1444/LTC1445
SYMBOL PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
t
PD
Propagation Delay
Overdrive = 10mV, C
OUT
= 100pF
12
s
Overdrive = 100mV, C
OUT
= 100pF
4
s
V
OH
Output High Voltage
I
O
= 15mA; LTC1443/LTC1445
q
V
+
0.4V
V
V
OL
Output Low Voltage
I
O
= 1.8mA; LTC1443
q
GND + 0.4V
V
I
O
= 1.8mA; LTC1444/LTC1445
q
V
+ 0.4V
V
Reference
V
REF
Reference Voltage
No Load, LTC1443
C Temp Range
q
1.170
1.182
1.194
V
I Temp Range
q
1.164
1.200
V
No Load, LTC1444/
C Temp Range
q
1.209
1.221
1.233
V
LTC1445
I Temp Range
q
1.203
1.239
V
I
SOURCE
Reference Output Source Current
V
REF
1mV
q
100
200
A
I
SINK
Reference Output Sink Current
V
REF
2.5mV
10
15
A
V
REF
5mV
q
10
15
A
Noise
Voltage Noise
100Hz to 100kHz
100
V
RMS
The
q
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25
C. V
+
= 5V, V
= GND = 0V, unless otherwise noted.
The
q
denotes the specifications which apply over the full operating temperature range, otherwise specifications are at T
A
= 25
C.
V
+
= 3V, V
= GND = 0V, unless otherwise noted.
Note 1: Absolute Maximum Ratings are those values beyond which the life
of the device may be impaired.
ELECTRICAL CHARACTERISTICS
SYMBOL PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
Power Supply
V
+
Supply Voltage Range
q
2.0
11.0
V
I
CC
Supply Current
IN
+
= IN
= 80mV, HYST = REF
q
5
8
A
Comparator
V
OS
Comparator Input Offset Voltage
V
CM
= 1.5V
q
3.0
10.0
mV
I
IN
Input Leakage Current (IN
+
, IN
)
V
IN
+
= V
IN
= 1.5V
q
0.01
1.0
nA
Input Leakage Current (HYST)
LTC1444/LTC1445
q
0.02
1.0
nA
V
CM
Comparator Input Common Mode Range
q
V
V
+
1.3V
V
CMRR
Common Mode Rejection Ratio
V
to (V
+
1.3V)
0.1
1.0
mV/V
PSRR
Power Supply Rejection Ratio
V
+
= 2V to 11V
0.1
1.0
mV/V
Noise
Voltage Noise
100Hz to 100kHz
100
V
RMS
V
HYST
Hysteresis Input Voltage Range
LTC1444/LTC1445
q
REF 50mV
REF
V
t
PD
Propagation Delay
Overdrive = 10mV, C
OUT
= 100pF
14
s
Overdrive = 100mV, C
OUT
= 100pF
5
s
V
OH
Output High Voltage
I
O
= 10mA, LTC1443/LTC1445
q
V
+
0.4V
V
V
OL
Output Low Voltage
I
O
= 0.8mA; LTC1443
q
GND + 0.4V
V
I
O
= 0.8mA; LTC1444/LTC1445
q
V
+ 0.4V
V
Reference
V
REF
Reference Voltage
No Load, LTC1443
C Temp Range
q
1.170
1.182
1.194
V
I Temp Range
q
1.164
1.200
V
No Load, LTC1444/
C Temp Range
q
1.209
1.221
1.233
V
LTC1445
I Temp Range
q
1.203
1.239
V
I
SOURCE
Reference Output Source Current
V
REF
1mV
q
60
120
A
I
SINK
Reference Output Sink Current
V
REF
2.5mV
10
15
A
V
REF
5mV
q
10
15
A
Noise
Noise Voltage
100Hz to 100kHz
100
V
RMS
4
LTC1443/LTC1444/LTC1445
LTC1444/LTC1445
Hysteresis Control
V
REF
V
HYST
(mV)
0
IN
+
IN
(mV)
20
0
20
30
50
LTC1443/44/45 TPC01
40
60
80
10
20
40
40
60
80
Supply Current vs Supply Voltage
Supply Current vs Temperature
SUPPLY VOLTAGE (V)
1.0
4.0
SUPPLY CURRENT (
A)
4.2
4.4
4.6
4.8
5.0
5.2
1.5
2.0
2.5
3.0
LTC1443/44/45 TPC02
T
A
= 25
C
TEMPERATURE (
C)
60
SUPPLY CURRENT (
A)
20
5.8
5.4
5.0
4.6
4.2
3.8
3.4
3.0
LTC1443/44/45 TPC03
20
60
40
40
0
80 100 120
IN
+
= (IN
+ 100mV)
V
= GND (LTC1443)
V
+
= 3V
V
= 0V
V
+
= 5V
V
= 0V
V
+
= 5V
V
= 5V
LTC1444/LTC1445 Reference
Voltage vs Temperature
TEMPERATURE (
C)
60
1.208
REFERENCE VOLTAGE (V) 1.212
1.216
1.220
1.224
40 20
0
20
LTC1443/44/45 TPC04
40
60
80 100 120
V
+
= 5V
TEMPERATURE (
C)
60
REFERENCE VOLTAGE (V)
1.186
1.184
1.182
1.180
1.178
1.176
1.174
1.172
1.170
100
LTC1443/44/45 TPC05
20
20
60 80
40
0
40
120 140
V
+
= 5V
V
= GND
LTC1443 Reference Voltage
vs Temperature
LOAD CURRENT (mA)
REFERENCE VOLTAGE (V)
1.184
1.183
1.182
1.181
1.180
1.179
1.178
0.2
0.4
0.6
0.8
LTC1443/44/45 TPC06
1.0
0.1
0
0.3
0.5
0.7
0.9
V
+
= 5V
V
= GND
T
A
= 25
C
SOURCE
LTC1443 Reference Output
Voltage vs Output Load Current
LTC1443 Reference Output
Voltage vs Output Load Current
Comparator Output Voltage High
vs Load Current
Comparator Output Voltage Low
vs Load Current
LOAD CURRENT (
A)
0
REFERENCE OUTPUT VOLTAGE (V)
20
1.194
1.192
1.190
1.188
1.186
1.184
1.182
1.180
LTC1443/44/45 TPC07
10
30
5
25
15
35
40
45
V
+
= 5V
V
= GND
T
A
= 25
C
SINK
LOAD CURRENT (mA)
0
1.0
OUTPUT VOLTAGE HIGH (V)
2.0
3.0
4.0
5.0
10
20
30
40
LTC1443/44/45 TPC08
50
60
V
+
= 5V
V
+
= 3V
V
+
= 2V
T
A
= 25
C
LOAD CURRENT (mA)
0
OUTPUT VOLTAGE HIGH (V)
1.5
2.0
2.5
30
50
80
LTC1443/44/45 TPC09
1.0
0.5
0
10
20
40
60
70
V
+
= 2V
V
+
= 3V
V
+
= 5V
T
A
= 25
C
TYPICAL PERFOR A CE CHARACTERISTICS
U
W
5
LTC1443/LTC1444/LTC1445
RESPONSE TIME (
s)
1
INPUT VOLTAGE (mV)
OUTPUT VOLTAGE (V)
100
0
1
6
4
5
LTC1443/44/45 TPC10
0
2
0
10
8
2
3
4
100mV
10mV
50mV
20mV
T
A
= 25
C
Comparator Response Time vs
Input Overdrive
Comparator Response Time vs
Input Overdrives
RESPONSE TIME (
s)
1
INPUT VOLTAGE (mV)
OUTPUT VOLTAGE (V)
0
0
1
6
14
18
5
LTC1443/44/45 TPC11
100
2
10
4
12
16
0
8
2
3
4
100mV
10mV
50mV
20mV
T
A
= 25
C
Comparator Short-Circuit Sink
Current vs Supply Voltage
SUPPLY VOLTAGE (V)
0
SINK CURRENT (mA)
200
180
160
140
120
100
80
60
40
20
0
8
LTC1443/44/45 TPC12
2
1
3
5
7
9
4
6
10
OUT CONNECTED TO V
+
T
A
= 25
C
Comparator Response Time vs
Load Capacitance
LOAD CAPACITANCE (nF)
0
RESPONSE TIME (
s)
12
10
8
6
4
2
80
LTC1443/44/45 TPC14
20
40
60
100
t
PHL
t
PLH
Comparator Short-Circuit Source
Current vs Supply Voltage
SUPPLY VOLTAGE (V)
0
SOURCE CURRENT (mA)
3
5
LTC1443/44/45 TPC13
1
2
4
160
140
120
100
80
60
40
20
0
OUT CONNECTED TO
V
= GND = 0V
Comparator Response Time at
Low Supply Voltage
Supply Current vs
Comparator Input Frequency
INPUT FREQUENCY (Hz)
1
SUPPLY CURRENT (
A)
10000
1000
100
10
1
100
10k
100k
10
1k
LTC1329 TPC15
C
OUT
= 55pF
C
OUT
= 15pF
C
OUT
= 5pF
SUPPLY VOLTAGE (V)
1
RESPONSE TIME (
s)
10000
1000
100
10
1
1.2
1.4
1.6
1.1
1.3
1.5
LTC1443/44/45 TPC16
20mV OVERDRIVE
100mV OVERDRIVE
TYPICAL PERFOR A CE CHARACTERISTICS
U
W
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